| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
(Hypertension. 2001;37:365.)
© 2001 American Heart Association, Inc.
Scientific Contributions |
Antisense Inhibition of Thyrotropin-Releasing Hormone Reduces Arterial Blood Pressure in Spontaneously Hypertensive Rats
From the Cardiología Molecular, Instituto de Investigaciones Médicas A. Lanari, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
Correspondence to Dr Carlos J. Pirola, Instituto de Investigaciones Médicas A. Lanari, Combatientes de Malvinas 3150, 1427- Buenos Aires, Argentina. E-mail cjpirola{at}ciudad.com.ar/sigarcia@ciudad.com.ar
 |
Abstract |
|---|
 Top Abstract IntroductionMethodsResultsDiscussionReferences |
|---|
Thyrotropin-releasing hormone (TRH) plays an important role in central cardiovascular regulation. Recently, we described that the TRH precursor gene overexpression induces hypertension in the normal rat. In addition, we published that spontaneously hypertensive rats (SHR) have central extrahypothalamic TRH hyperactivity with increased TRH synthesis and release and an elevated TRH receptor number. In the present study, we report that intracerebroventricular antisense (AS) treatment with a phosphorothioate oligonucleotide against the TRH precursor gene significantly diminished up to 72 hours and in a dose-dependent manner the increased diencephalic TRH content, whereas normalized systolic blood pressure (SABP) was present in the SHR compared with Wistar-Kyoto (WKY) rats. Although basal thyrotropin was higher in SHR compared with WKY rats and this difference disappeared after antisense treatment, no differences were observed in plasma T4 or T3 between strains with or without AS treatment, indicating that the effect of the AS on SABP was independent of the thyroid status. Because the encephalic renin-angiotensin system seems to be crucial in the development and/or maintenance of hypertension in SHR, we investigated the effect of antisense inhibition of TRH on that system and found that TRH antisense treatment significantly diminished the elevated diencephalic angiotensin II (Ang II) content in the SHR without any effect in control animals, suggesting that the Ang II system is involved in the TRH cardiovascular effects. To summarize, the central TRH system seems to be involved in the etiopathogenesis of hypertension in this model of essential hypertension.
Key Words: angiotensin II • antisense • blood pressure • hypertension • SHR • thyroid hormones • TRH • TSH
|
Introduction |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
In addition to its endocrine function, thyrotropin-releasing hormone (TRH; pyro-Glu-His-Pro-amide) also serves as a neurotransmitter in the central nervous system.1 TRH immunoreactivity is widely distributed throughout the central nervous system, including the brain and spinal cord.2 Although the lack of antagonists to the TRH receptor has made difficult to determine the physiological role for the extrahypothalamic TRH system, its presence in brain nuclei involved in cardiovascular regulation, such as the periventricular region and the preoptic area, suggests that this tripeptide may modulate the cardiovascular function.3 In fact, many groups have described that brain microinjections of TRH produce dose-dependent pressor effects.4
Recently, we have reported that the overexpression of the TRH precursor in the third ventricle of the central nervous system of normal rats induces a long-lasting elevation of arterial blood pressure along with an increase in the diencephalic TRH content in a dose-dependent manner. These effects were specifically reversed by an antisense treatment, indicating that the extrahypothalamic TRH system effectively participates in cardiovascular regulation in the rat.5
Spontaneously hypertensive rats (SHR) have been extensively used as an essential hypertension model. In these rats, an enhanced brain angiotensin system, and a muscarinic cholinergic hyperactivity have been detected that may participate in the development or maintenance of hypertension.6 7 On the other hand, we have shown that TRH facilitates the pressor response to centrally infused acetylcholine, increasing the number of muscarinic receptors. In turn, in vitro superfusion experiments with preoptic area slices showed that cholinergic muscarinic stimulation evoked a specific TRH release.8 In addition, it has been described that spontaneously hypertensive rats exhibit a supersensitivity to the hypertensive effects of exogenous TRH.9 Accordingly, in a previous study, we published that SHR presented an increase of both, TRH content and TRH precursor mRNA abundance in the preoptic area with a higher cerebrospinal fluid TRH concentration and an augmented TRH receptor number in this area compared with its control normotensive strain Wistar-Kyoto (WKY). In addition, we also found that a polyclonal antibody raised against TRH infused peripherally or intracerebroventricularly significantly decreased arterial blood pressure.10 These results pointed out that, in addition to the regulation of the cardiovascular system in a normal rat, extrahypothalamic TRH may participate in the pathogenesis of the hypertension in this genetic model. However, the question as to whether an increased activity of the TRH system is responsible for the hypertension, either by a direct action or through the activation of other mechanisms, in the abnormal biochemical environment of the central nervous system of the SHR, remains to be answered.
Antisense molecules have been used to successfully inhibit protein synthesis in several biological systems. They can bind to a complementary region of the target gene and/or mRNA and block selected gene expression without changing the functions of other genes.11 Therefore, we conclude that the AS strategy may be a good option for a gene therapy approach to inhibit TRH. Consequently, in the present study, we attempted to reduce the production of TRH in the diencephalic region by administration of antisense phosphorothioate oligonucleotides against the translation initiation codon region of the TRH-precursor gene and analyze whether the TRH antisense treatment is able to normalize the blood pressure in the SHR. We found that a single intracerebroventricular antisense injection decreased both the elevated diencephalic TRH content and the systolic blood pressure (SABP) for up to 72 hours only in the SHR strain in a dose-dependent manner, whereas sense or vehicle treatment failed. Normalization of blood pressure seems to be independent of changes in thyroid status, since, although basal plasma thyroid-stimulating hormone (TSH) was increased in SHR with respect to its control and TRH antisense treatment reduced TSH, there were no changes in plasma thyroid hormone levels.
As we pointed out above, the interactions between systems involved in the cardiovascular regulation are still unknown. Because the brain renin-angiotensin system is considered important for cardiovascular regulation and it has been reported that SHR present an augmented central angiotensin II (Ang II) synthesis and Ang II receptor number, and antisense treatments against angiotensinogen, angiotensin converting enzyme, or the angiotensin type I receptor (AT1) normalizes blood pressure in these animals,12 13 14 15 16 we also measured diencephalic Ang II content in our experiments. We found that TRH antisense treatment decreases the Ang II diencephalic content to values comparable to those of the WKY control rats
To summarize, these results pointed out that (1) the central TRH system participates in the development or maintenance of hypertension in this rat model, and (2) the TRH cardiovascular effects are independent of its classic endocrine function in the hypothalamus-pituitary axis and seems to involve the encephalic renin-angiotensin system.
|
Methods |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Animals
Adults (16-week-old, 250 to 300 g) male SHR of the Okamoto-Aoki strain and age-matched male normotensive WKY rats were housed in a room with a control temperature (23±1°C) under a 12-hour light/dark schedule. Food and water were given ad libitum. Animal experimentation protocols were approved by our Institutional Animal care and Use Committee.
Intracerebroventricular
Oligonucleotide Treatment
SHR and WKY males were anesthetized with
pentobarbital (45 mg/kg). A 25-gauge stainless steel cannula was
directed to the third ventricle through a burr hole in the skull for
injection with the aid of a stereotaxic
atlas.17 Coordinates for
injection were 1.3 mm posterior to the bregma on the midline and
4.5 mm below the dura. Oligonucleotides were
dissolved in phosphate-buffer-saline (PBS). At the end of each
experiment, the position of the cannula was assessed by histologic
examination. A total injection volume of 10 µL was used. Control rats
received vehicle only.
SABP and heart rate were recorded daily during the experiments by the tail-cuff plethysmographic method. Basal values correspond to the mean of 3 independent measurements during 3 days before the injection. Daily SABP was the average of 3 measurements taken 2 minutes apart. In separate sets of experiments, animals were killed by decapitation at different time points after intracerebroventricular injection. The brain tissue was processed as described below.
Oligonucleotides were made resistant to nucleases by DNA backbone phosphorothioation and were synthesized (Biosynthesis Inc) as 23-mers targeted to bases 20 to 42 (AS: 5'AAC CAA GGT CCC GGC ATC CTG GA 3') of rat pre-TRH gene encompassing the translation initiation codon (GenBank accession number M23643). As control, we used a sense oligonucleotide (S: 5' TCC AGG ATG CCG GGA CCT TGG TT 3'). The screening of known rat genes from the genomic database of the National Center for Biological Information (NCBI) using the Blast program indicates specificity of the sequences used in oligonucleotides design and confirms their 100% homology with rat pre-TRH gene. AS and S: high score 115 for pairs with rat TRH sequences M23643, M12138 and M36317. Oligonucleotides were dissolved in PBS and 25, 50, 100 or 200 µg ICV were injected in a total volume of 10 µL.
Diencephalic TRH Content Determination by
Radioimmunoassay
Animals were killed by decapitation and brains were
rapidly removed. The diencephalic region of each animal was rapidly
dissected with the aid of a stereotaxic atlas. To avoid the
degradation of authentic TRH and the formation of TRH-like substances,
samples (1 diencephala) were boiled in 2 mol/L acetic acid, 100
mmol/L HCl for 20 minutes, homogenized, and
centrifuged at 10 000 g for 10 minutes. The supernatants
were lyophilized, and residues were dissolved in radioimmunoassay (RIA)
buffer. We confirmed that 90% of TRH-like immunoreactivity correspond
to authentic TRH using a previously reported
chromatographic method that consists of a SP-Sephadex C25
and high-performance liquid
chromatography.8
RIA for TRH has been described in detail.8 In brief, a polyclonal anti-TRH antibody was raised in New Zealand White rabbits immunized with TRH coupled to bovine serum albumin using the bis-diazotized benzidine reaction. Standards or samples were incubated with 125I- and anti-TRH (1/10 000) at 4°C overnight. Bound hormone was pelleted with rabbit normal serum and a second antibody against rabbit IgG. All samples were assayed in duplicate. The minimum detectable amount was 5 to 10 pg. Intra-assay and interassay coefficients of variation were less than 7.0% and 14.0%, respectively.
Determination of TSH and Thyroid Hormones
in Plasma
Blood samples were collect on EDTA-containing tubes,
and plasma was obtained by centrifugation. TSH was
carefully determined by Dr P. Hacke (BsAs) using a previously published
RIA (kit NIDDK) using rTSH RP3 (AFP-5512B) as TSH standard, and
anti-rat TSH (RIA 6). Total plasma T4 and T3 concentrations were
measured using electrochemiluminescence immunoassay (kits 1010 and
2010, Roche).
Diencephalic Ang II Content Determination
by RIA
For the Ang II determination, samples were processed
identically as the samples described for TRH determinations using a RIA
developed in our
laboratory.18 In brief, a
polyclonal anti–Ang II antibody was raised in New Zealand White
rabbits immunized with Ang II coupled to bovine serum albumin
using glutaraldehyde (2.5 mg/L). Standards or samples
were incubated with 125I- and anti–Ang II
(1/15 000) at 4°C overnight. Bound hormone was pelleted with
rabbit normal serum and a second goat antibody against rabbit IgG. All
samples were assayed in duplicate. The minimum detectable amount was 5
to 10 pg. Intra-assay and interassay coefficients of variation were
less than 9.0% and 16.0%, respectively.
Statistical Analysis
Results are expressed as mean±SD from independent
experiments. Statistical significance between means for the effects of
treatments on SABP were determined by 2-way ANOVA with
repeated-measurements on one factor. Where pairwise comparisons were
made after ANOVA, the Tukey’s test for individual differences was
used.
|
Results |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
In this study, we confirm our previous observations of the elevated SHR diencephalic TRH content with respect to their age-matched WKY. In addition, we show that a phosphorothioate TRH antisense treatment injected intracerebroventricularly decreases the increased diencephalic TRH content (diencephalic TRH ng/mg protein) with a maximum effect at 24 hours after antisense injection up to 72 hours, only in the SHR, whereas sense and control treatment failed (Figure 1). No differences were observed between antisense or sense treatments compared with vehicle-treated WKY animals at all time points.
|
As shown in Figure 2, basal SABP was significantly higher in the SHR with respect to their controls WKY (SHR: 161±7 versus WKY 111±8 mm Hg, n=8, P<0.02). TRH antisense treatment decreased the elevated SABP of SHR with a maximum effect at 24 hours up to 72 hours, whereas sense and control treatments had no effect. No differences were observed in the arterial blood pressure of the control WKY rats among antisense, sense, and vehicle treatments throughout the experiments.
|
In addition, in SHR, we observed that SABP and diencephalic TRH content reductions were dependent on antisense oligonucleotide doses, reaching a plateau at 100 µg (Figure 3). No significant changes were observed in heart rate with antisense, sense, or vehicle treatments in both strains (data not shown).
|
As shown in Figure 4, TSH concentrations in plasma were significantly elevated (more than 2-fold) in SHR compared with WKY control rats. TRH antisense intracerebroventricular injection significantly reduced TSH plasma levels to similar values of those of WKY control rats, 24 hours after treatment. There were no differences between thyroid hormones (T3 ng/mL and T4 µg/dL) in basal conditions between both strains and antisense; sense and vehicle treatments had no effects on thyroid status in these animals.
|
At 24 hours after injection, when the hypotensive effect peaked, the TRH antisense treatment also significantly reduced the increased diencephalic Ang II content (pg/mg protein) of the SHR to values comparable with those found in WKY normotensive rats, whereas the sense and vehicle treatments failed to produce any changes in both strains (Table).
|
|
Discussion |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
In physiological studies, intravenous or intracerebroventricular TRH injections increased arterial blood pressure.4 This effect was blocked by destruction of the sympathetic system, indicating that the pressor effect could be mediated by catecholamines involving the modulations of diverse neurotransmitter system activity.19
In 1995, we reported for the first time that SHR show a significant hyperactivity of the extrahypothalamic TRH system with a 2-fold increase of the preoptic hypothalamic area TRH content and TRH receptor number along with a significantly increased TRH concentration in the cerebrospinal fluid. These findings, in addition to the Northern blot analysis indicating a 3-fold augmented TRH precursor mRNA, have pointed out that SHR present increases in the TRH synthesis and release in the central nervous system. A significant hyperactivity of the TRH system was also apparent at the prehypertensive stage of these rats, indicating that alterations in this system may participate in both the development and maintenance of the hypertension in this model.10 Because until now, no specific antagonist is available for the TRH receptor in that previous work, as a first approach, we have analyzed the effect of a polyclonal antibody against TRH injected peripherally or intracerebroventricularly and found a significant but very short-lasting hypotensive effect, probably because of the presence of neutralizing endogenous TRH and the difficulty of big molecules to reach the synaptic space.10 However, it remains controversial as to whether the increased expression of the extrahypothalamic TRH system in the spontaneously hypertensive strain is the cause of the elevated arterial blood pressure.
In the present study, we assessed in the SHR the TRH antisense treatment that was proved to be efficient as strategy for antagonising the TRH cardiovascular effects in the normal rat with induced TRH overproduction.5 Therefore, we report, for the first time that a TRH antisense single intracerebroventricular injection reduced the augmented diencephalic TRH content and normalizes arterial blood pressure of the SHR, without any effect in the WKY normotensives rats. The TRH AS-induced decrease in the SABP of the SHR is related to the reduction in diencephalic TRH content, because we observed no changes in other TRH-containing brain areas such as amygdala or olfactory bulb (data not shown). Even though the explanation for the absence of any effect of the TRH antisense treatment in the normotensive strain is not apparent, one possibility is that a very low turnover of the endogenous TRH system would be unaffected by a single TRH antisense injection or that, under normal conditions, the TRH system does not exert a tonic effect on central cardiovascular regulation. Decreases of diencephalic TRH content and systolic blood pressure induced by the TRH antisense treatment show an onset of less than 24 hours and decline at 72 hours. This rapid onset may suggest that there is a high turnover of the periventricular TRH in the SHR. On the other hand, these transitory effects are what can be expected for a single antisense injection of the oligonucleotide, which, even though it has been made resistant to nucleases by phosphorothioation, may still suffer a significant degradation rate.20 In fact, a similar time course has been observed for other antisense treatments.21 In any case, using this approach we were able to demonstrate the effectiveness of the antisense oligonucleotide treatment in decreasing arterial blood pressure in the SHR. Accordingly, Suzuki et al22 reported that antisense inhibition of TRH receptor gene expression induced similar effects on SABP in this hypertensive strain.
The observed effects of the TRH antisense oligonucleotide is sequence specific and seem not due to a nonspecific toxicity, because treatment with sense oligonucleotide, which had a similar percentage base composition, showed no effects. We have no evidence supporting the final mechanisms of action of the antisense, which can act by decreasing the pre-TRH mRNA abundance at a transcriptional or posttranscriptional level and/or inhibiting the pre-TRH mRNA translation machinery, but the decrease of the tripeptide content in the diencephalon means that the treatment was an effective blocker of the precursor TRH production. Although those experiments were not focused on the TRH activity of the hypothalamic-pituitary axis, another possible site of action of the antisense oligonucleotides to TRH is the hypothalamus, where alterations in the TRH synthesis might affect thyroid function indirectly influencing the cardiovascular tone. SHR are characterized by several neuroendocrine abnormalities, including a chronic hypersecretion of TSH of unknown etiology associated with normal plasma T3 and T4 levels.23 This inappropriately high TSH secretion in euthyroid SHR may be the result of an impaired hormone negative feedback regulation of the central TRH system or a inappropriate pituitary TSH production.24 Accordingly to other authors and our own previous data, we showed that SHR in basal conditions present a higher (3-fold) plasma TSH concentration compared with control WKY rats.10 25 In the present study, plasma samples were collected 24 hours after the injection when antisense treatment reached its maximum hypotensive effect and we found that TRH antisense treatment normalize plasma TSH in SHR without affecting TSH levels in control rats. Despite this effect of antisense treatment on TSH level of the SHR, no differences were observed in plasma T4 and T3 between strains with or without antisense treatment. The euthyroid state of the SHR, despite of altered plasma TSH levels, has not yet been explained and deserves further investigation, but either a decrease in thyroid TSH receptors or an abnormal TSH biological activity can be implied.26 At any rate, our findings indicate that TRH antisense induced hypotensive effect does not seem to be explained by changes in the thyroid status. Additional studies are necessary to delineate the complex interactions that may take place in the effect of the extrahypothalamic TRH system in cardiovascular regulation but TRH cardiovascular effects seem to be rather mediated by the sympathetic system, because TRH injections produce an increase in plasma catecholamine levels, and adrenalectomy avoids its hypertensive effects.19 Accordingly, it is tempting to speculate that a TRH antisense-induced fall in the sympathetic activity would produce more obvious effects in SHR because of their higher sympathetic tone compared with WKY control animals.27 Because TRH is a potent prolactin releaser,28 it can be hypothesized that anti-sense treatment against TRH may decrease SABP by affecting prolactin levels. We cannot reject that possibility because we have not measured prolactin, but this seems unlikely because prolactin has been described not to be involved in the pathogenesis of the hypertension in the SHR.29 In addition, prolactin may not alter arterial blood pressure directly and may require a week to potentiate the pressor effect of norepinephrine.30 In any case, the participation of prolactin in the TRH antisense effects remains to be explored.
On the other hand, the vast interactions between neurotransmitters and neuropeptide systems involved in the cardiovascular regulation are still unknown. The brain renin-angiotensin system is considered one of the most important in the blood pressure control either by a direct action or through the activation of other neurohumoral mechanisms. The augmented central Ang II production with an increased Ang II receptor number is a common reported feature of the SHR.6 31 A growing body of evidence shows that antisense treatments against angiotensinogen, angiotensin converting enzyme, or AT1 receptor normalizes blood pressure in the SHR.12 13 14 32 33 Therefore, we measured Ang II diencephalic content in this model. We found that TRH antisense treatment decreases the elevated Ang II diencephalic content to values comparable to the WKY control rats without any effects in the WKY control animals. Taking into account the theoretical high specificity of the TRH antisense treatment (100% homology with precursor TRH gene), the decrease on diencephalic Ang II content suggest that the TRH may exert some regulation over the angiotensin system. A note of caution should be mentioned here, it is not possible to infer from changes in neuropeptide content as to whether those are produced by alterations in neuropeptide synthesis and/or release. In fact, if one assumes that antisense–induced Ang II content decrease is the result of a diminished synthesis, then TRH exerts a positive effect on the Ang II system; conversely, if one assumes that the Ang II content decrease means a higher release rate of Ang II, then this change in Ang II may be interpreted as a compensatory mechanism induced by the fall in arterial blood pressure with no biochemical connection with the TRH system. For that reason, it should be mentioned that we were not able to show either a corresponding increase in diencephalic Ang II content in basal conditions or its decrease after antisense treatment in our TRH overproduction rat model, suggesting that an Ang II-TRH interaction may require the altered neurochemical environment that characterizes the brain of SHR. Consequently, more investigations are necessary to determine the reach of this intriguing interaction between both neuropeptide systems.
To conclude, we believe that these results demonstrate the important role that the extrahypothalamic TRH system plays in the development and/or maintenance of the elevated arterial blood pressure in this genetic hypertensive rat model. TRH cardiovascular effects are not mediated by thyroid hormones and seem to involve the angiotensin system.
|
Acknowledgments |
|---|
This work was supported by grants PICT 00756 (Agencia Nacional de Promoción Científica y Tecnológica), TM 065 and 085 (Universidad de Buenos Aires), PIPs 901/98 and 1045/98 (Consejo Nacional de Investigaciones Científicas y Técnicas), and Beca Ramón Carrillo-Arturo Oñativia (Ministerio de Salud Pública de la Nación).
Received October 26, 2000; first decision November 30, 2000; accepted December 13, 2000.
|
References |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
1. Bhargava HN, Das S. Evidence for opiate action at the brain receptors for thyrotropin releasing hormone. Brain Res. 1986;368:262–267.[Medline] [Order article via Infotrieve]
2. Eskay RL, Long RT, Palkovits M. Localisation of immunoreactive thyrotropin releasing hormone in the lower brainstem of the rat. Brain Res. 1983;277:159–162.[Medline] [Order article via Infotrieve]
3.
Brownstein MJ,
Palkovits M, Saavedra JM, Bassiri RM, Utiger RD. Thyrotropin releasing
hormone in specific nuclei of rat brain.
Science. 1974;185:267–269.
4. Siren AL, Pakkari I. Cardiovascular effects of TRH i.c.v. in conscious rats. Clin Exp Hypertens A. 1984;6:2073–2077.[Medline] [Order article via Infotrieve]
5.
García SI, Porto
PI, Alvarez AL, Martinez VN, Shaurli D, Finkielman S, Pirola CJ.
Central overexpression of the TRH precursor gene induces hypertension
in rats: antisense reversal.
Hypertension. 1997;30:759–766.
6.
Ganten D, Hermann K,
Bayer C, Unger T, Lang RE. Angiotensin synthesis in the
brain and increased turnover in hypertensive rats.
Science. 1983;221:869–871.
7. Scheucher A, Alvarez AL, Torres N, Dabsys SM, Finkielman S, Nahmod VE, Pirola CJ. Cholinergic hyperactivity in the lateral septal area of spontaneously hypertensive rats: depressor effect of hemicholinium-3 and pirenzepine. Neuropharmacology. 1991;30:391–395.[Medline] [Order article via Infotrieve]
8.
García SI, Dabsys
SM, Santajuliana DO, Delorenzi A, Finkielman S, Nahmod VE, Pirola
CJ. Interaction between thyrotropin-releasing hormone and the
muscarinic cholinergic system in rat brain.
J Endocrinol. 1992;134:215–219.
9. Bansinath M, Das S, Bhargava HN. Spontaneous hypertensive rats exhibit supersensitivity to hypertensive and hyperthermic effects of thyrotropin releasing hormone. Peptides. 1987;8:227–230.[Medline] [Order article via Infotrieve]
10.
García SI,
Dabsys SM, Martinez VN, Santajuliana DO, Nahmod VE, Finkielman S,
Pirola CJ. Thyrotropin-releasing hormone hyperactivity in the preoptic
area of spontaneously hypertensive rats.
Hypertension. 1995;26:1105–1110.
11. Wagner RW. Gene inhibition using antisense oligodeoxynucleotides. Nature. 1994;372:333–335.[Medline] [Order article via Infotrieve]
12.
Makino N, Sugano
M, Ohtsuka S, Sawada S, Hata T. Chronic antisense therapy for
angiotensinogen on cardiac hypertrophy in
spontaneously hypertensive rats.
Cardiovasc Res. 1999;44:543–548.
13. Phillips MI. Gene therapy for hypertension: antisense inhibition with adeno-associated viral vector delivery targeting angiotensin II type-1 receptor messenger ribonucleic acid. Am J Cardiol. 1998;82:60S. Abstract.[Medline] [Order article via Infotrieve]
14. Raizada MK, Francis SC, Wang HW, Gelband CH, Reaves PY, Katovich MJ, Targeting of the renin-angiotensin system by antisense gene therapy: a possible strategy for the long-term control of hypertension. J Hypertens. 2000;18:353–362.[Medline] [Order article via Infotrieve]
15.
Wang HW, Reaves
PY, Gardon ML, Keene K, Goldberg DS, Gelband CH, Katovich MJ, Raizada
MK, Angiotensin I-converting enzyme antisense gene therapy
causes permanent antihypertensive effects in the SHR.
Hypertension. 2000;35:202–208.
16. Tang XP, Mohuczy D, Zhang YC, Kimura B, Galli SM, Phillips MI, Intravenous angiotensinogen antisense in AAV-based vector decreases hypertension. Am J Physiol. 1999;277(pt 2):H2392–H2399.
17. Thompson R. A Behavioural Atlas of the Rat Brain. Cambridge, UK: Oxford University Press; 1978.
18. Delorenzi A, Pedreira ME, Romano A, García SI, Pirola CJ, Nahmod VE, Maldonado H. Angiotensin II enhances long-term memory in the crab Chasmagnathus. Brain Res Bull. 1996;41:211–220.[Medline] [Order article via Infotrieve]
19. Mattila J, Bunag RD. Sympathetic pressor response to thyrotropin-releasing hormone in rats. Am J Physiol. 1986;251:H86–H92.
20. Wagner RW. The state of the art in antisense research. Nat Med. 1995;1:1116–1121.[Medline] [Order article via Infotrieve]
21.
Tomita N,
Morishita R, Higaki J, Aoki M, Nakamura Y, Mikami H, Fukamizu A,
Murakami K, Kaneda Y, Ogihara T. Transient decrease in high blood
pressure by in vivo transfer of antisense
oligodeoxynucleotides against rat
angiotensinogen.
Hypertension. 1995;26:131–136.
22.
Suzuki S, Pilowsky
P, Minson J, Arnolda L, Llewellyn-Smyth I, Chalmers J. Antisense to
thyrotropin releasing hormone receptor reduces arterial
blood pressure in spontaneously hypertensive rats.
Circ Res. 1995;77:679–683.
23. Kojima A, Takahashi Y, Ohno SI, Sato A, Yamada T, Kubota T, Yamori Y, Okamoto K. An elevation of plasma TSH concentration in SHR. Proc Soc Exp Biol Med. 1975;149:661–663.[Medline] [Order article via Infotrieve]
24. Bruhn TO, Jackson IMD. Abnormalities of the thyroid hormone negative feedback regulation of TSH secretion in spontaneously hypertensive rats. Regul Pept. 1993;38:221–230.
25. Werner SC, Manger WM, Radichevich I, Wolff M, Von Estorff I. Excessive thyrotropin concentrations in the circulation of the spontaneously hypertensive rat. Proc Soc Exp Biol Med. 1975;148:1013–1017.[Medline] [Order article via Infotrieve]
26.
Beck-Peccoz P,
Persani L. Variable biological activity of thyroid-stimulating
hormone. Eur J Endocrinol. 1994;131:331–340.
27. Judy WV, Watanabe AM, Henry DP, Besch HR, Murphy WR, Hockel GM. Sympathetic nerve activity: role in the regulation of blood pressure in the spontaneously hypertensive rat. Circ Res. 1976;38:21–29.[Abstract]
28. Josephbravo P, Uribe RM, Vargas MA, Perezmartinez L, Zoeller T, Charli JL. Multifactorial modulation of TRH metabolism. Cell Mol Neurobiol. 1998;18:231–247.[Medline] [Order article via Infotrieve]
29. Mills DE, Ward RP. Antiserum to prolactin lowers blood pressure (BP) in spontaneously hypertensive rats. Proc Soc Exp Biol Med. 1985;178:317–320.[Medline] [Order article via Infotrieve]
30. Mills DE, Ward RP. Effect of prolactin on blood pressure and cardiovascular responsiveness in the rat. Proc Soc Exp Biol Med. 1986;181:3–8.[Medline] [Order article via Infotrieve]
31. Hermann K, McDonald W, Unger T, Lang RE, Ganten D. Angiotensin biosynthesis and concentration in brain of normotensive and hypertensive rats. J Physiol (Paris). 1984;79:471–480.[Medline] [Order article via Infotrieve]
32. Wang HW, Reaves PY, Gardon ML, Keene K, Goldberg DS, Gelband CH, Katovich MJ, Raizada MK, Angiotensin I-converting enzyme antisense gene therapy causes permanent antihypertensive effects in the SHR. Hypertension. 2000;35:202–208.
33.
Mohuczy D, Gelband
CH, Phillips MI. Antisense inhibition of AT(1) receptor in vascular
smooth muscle cells using adeno-associated virus-based vector.
Hypertension. 1999;33:354–359.
This article has been cited by other articles:
 |
|
 |
|
  A. A. da Silva, J. M. do Carmo, B. Kanyicska, J. Dubinion, E. Brandon, and J. E. Hall Response to Thyrotropin-Releasing Hormone Precursor Gene Knocking Down Impedes Melanocortin-Induced Hypertension in Rats Hypertension, August 1, 2008; 52(2): e9 - e9. [Full Text] [PDF]
|
|
|
|
 |
|
 M. S. Landa, S. I. Garcia, M. L. Schuman, A. Burgueno, A. L. Alvarez, F. E. Saravia, C. Gemma, and C. J. Pirola Knocking down the diencephalic thyrotropin-releasing hormone precursor gene normalizes obesity-induced hypertension in the rat Am J Physiol Endocrinol Metab, May 1, 2007; 292(5): E1388 - E1394. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
O. Gumieniak, T. S. Perlstein, J. S. Williams, P. N. Hopkins, N. J. Brown, B. A. Raby, and G. H. Williams Ala92 Type 2 Deiodinase Allele Increases Risk for the Development of Hypertension Hypertension, March 1, 2007; 49(3): 461 - 466. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 O. Gumieniak, S. Hurwitz, T. S. Perlstein, U. C. Ngumezi, P. N. Hopkins, X. Jeunemaitre, and G. H. Williams Aggregation of High-Normal Thyroid-Stimulating Hormone in Hypertensive Families J. Clin. Endocrinol. Metab., November 1, 2005; 90(11): 5985 - 5990. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. Agirregoitia, J. Gil, F. Ruiz, J. Irazusta, and L. Casis Effect of Aging on Rat Tissue Peptidase Activities J. Gerontol. A Biol. Sci. Med. Sci., September 1, 2003; 58(9): B792 - 797. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. I. Garcia, M. S. Landa, P. I. Porto, A. L. Alvarez, M. Schuman, S. Finkielman, and C. J. Pirola Thyrotropin-Releasing Hormone Decreases Leptin and Mediates the Leptin-Induced Pressor Effect Hypertension, February 1, 2002; 39(2): 491 - 495. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. E. De Wardener The Hypothalamus and Hypertension Physiol Rev, October 1, 2001; 81(4): 1599 - 1658. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. I. Garcia, P. I. Porto, G. Dieuzeide, M. S. Landa, T. Kirszner, Y. Plotquin, C. Gonzalez, and C. J. Pirola Thyrotropin-Releasing Hormone Receptor (TRHR) Gene Is Associated With Essential Hypertension Hypertension, September 1, 2001; 38(3): 683 - 687. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||