(Hypertension. 1999;33:360-365.)
© 1999 American Heart Association, Inc.
Scientific Contributions |
Angiotensin II Type 1 Receptor Antisense Gene Therapy Prevents Altered Renal Vascular Calcium Homeostasis in Hypertension
From the Department of Physiology, College of Medicine, and the Department of Pharmacodynamics, College of Pharmacy (M.J.K.), University of Florida, Gainesville, Fla.
Correspondence to Craig H. Gelband, PhD, Department of Physiology, College of Medicine, University of Florida, PO Box 100274, Gainesville, FL 32610. E-mail Gelband{at}phys.med.ufl.edu
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Abstract |
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Abstract—Intracellular Ca2+ ([Ca2+]i) homeostasis regulates vascular smooth muscle tone, and alteration in [Ca2+]i handling is associated with the development and establishment of hypertension. We have previously established in the spontaneously hypertensive rat (SHR) that virally mediated delivery of angiotensin II type 1 receptor antisense (AT1R-AS) prevents the development of high blood pressure and some pathophysiology associated with hypertension for 120 days. In light of this, our objectives in this study were to determine whether AT1R-AS gene therapy (1) could have a longer duration in the prevention of hypertension and (2) would attenuate the alterations in renal vascular Ca2+ homeostasis and therefore vasoconstriction, characteristics of hypertension. Intracardiac delivery of AT1R-AS in neonates prevented the development of hypertension in SHR for at least 210 days. At this time, untreated SHR renal resistance arterioles showed a significantly enhanced contractile response to KCl and angiotensin II (Ang II) when compared with normotensive Wistar-Kyoto rats. In addition, L-type Ca2+ current density and Ang II–dependent increases in [Ca2+]i were significantly increased in cells dissociated from renal resistance arterioles of the untreated SHR. AT1R-AS treatment prevented all of the above vascular alterations associated with the hypertensive state in SHR. Finally, Western blot analysis of L-type Ca2+ channel (
1C) protein levels in renal resistance
arterioles of untreated SHR showed no significant difference when
compared with control. These results are novel and demonstrate that
viral-mediated delivery of AT1R-AS not only attenuates the
development of hypertension on a long-term basis but prevents changes
in renal vascular Ca2+ homeostasis associated with the
disease.
Key Words: angiotensin II • arterioles • calcium, intracellular • Ca2+ current • excitation-contraction coupling • gene therapy
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Introduction |
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Essential hypertension is characterized by normal cardiac output and an increase in total peripheral resistance.1 Hypertension is one of the most important risk factors for stroke, congestive heart failure, myocardial infarction, end-stage renal diseases, and peripheral vascular disease.2 3 4 Studies from the last 2 decades have established that both circulating and tissue renin-angiotensin systems (RAS) are important, that their coordinated interaction is essential in the regulation of blood pressure, and that they play a key role in the development, establishment, and maintenance of hypertension.2 5 6
The relevance of the RAS to blood pressure control is further supported by reports that various genes that encode renin, angiotensinogen, angiotensin-converting enzyme (ACE), and the angiotensin II type 1 receptor (AT1R) have been associated with hypertension in both human and animal models.7 8 9 Additionally, interruption in the expression of the RAS attenuates high blood pressure and other pathophysiological aspects of hypertension.4 10 11 In fact, blockade of the RAS has become a well-accepted treatment for Ang-dependent hypertension and congestive heart failure.11 Because ACE inhibition and AT1R blockade are standard means to treat hypertension and because AT1R encoding gene polymorphism is coupled with hypertension in both humans and in animal models of hypertension,6 9 it would appear only logical that AT1R is an important target in the management of high blood pressure. Although major strides have been made in developing drugs that interfere with either angiotensin II (Ang II) formation or its action toward the management of Ang-dependent hypertension, there is neither a long-term preventive measure nor a cure for this disease.
The most widely used animal model for studying human essential hypertension is the spontaneously hypertensive rat (SHR). Pharmacological intervention has been relatively successful in normalizing the elevation in blood pressure associated with hypertension. However, the assumption that reduction of blood pressure will totally reverse hypertension-induced pathophysiological changes remains unclear. Several animal studies suggest that gene therapy would be useful in the treatment of hypertension. Olivero et al12 have shown that disruption of AT1R expression in mice causes blunting of pressor responses of Ang II. Phillips et al13 have used antisense oligonucleotides for the AT1R in the brain to reduce high blood pressure in SHR on a short-term basis. Recently, we have established that retrovirally mediated delivery of AT1R antisense (AT1R-AS) attenuates the development of high blood pressure on a long-term basis (up to 120 days) as well as prevents some of the pathophysiological alterations observed with the disease (eg, endothelial dysfunction, decreased K+ channel activity, increased heart weight, and increased cardiac and vascular fibrosis and necrosis) while having no inflammatory response.14 However, a more important pathophysiological alteration, the prevention of changes in cellular Ca2+ handling and therefore the level of vascular tone, has yet to be investigated.
Alterations in cellular Ca2+ homeostasis using 45Ca2+ flux, fluorometric, and patch-clamp measurements in large conduit SHR arteries and cells have been described.15 Renal transplant studies have suggested that the genetic defect in a proportion of the cases with essential hypertension is expressed in the kidney.16 Therefore, the resistance arterioles of the kidney are an important vasculature bed to study because alterations in renal blood flow are known to influence fluid volume regulation, the secretion of a number of important neurohumoral substances, and arteriolar resistance, which may be involved in the etiology or maintenance of hypertension. Our objective in this study was to determine whether this attenuation of high blood pressure was associated with the prevention of altered Ca2+ handling in cells from renal resistance arterioles induced by the hypertensive state.
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Methods |
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Preparation of Viral Particles Containing AT1R-AS
A retroviral vector, LNSV, was used to deliver AT1BR-AS into the rats as previously described.14 Briefly, the AT1BR-AS was cloned in the LNSV vector. It was transfected to packaging cell line PA317 (American Type Culture Collection). After selection by neomycin, the medium containing viral particles that expressed AT1BR-AS (LNSV-AT1R-AS) was collected and used for all animal experiments. Viral particles that did not contain AT1BR-AS (LNSV) were also prepared by the above protocol and used as a control. The AT1R-AS is believed to be specific for the AT1R because delivery of missense had no effect on AT1R number or the actions of Ang II in Wistar-Kyoto rats (WKY) or SHR.14 17 18 19
Animals and Experimental Protocols
Five-day-old WKY and SHR were divided into 3 treatment groups:
vehicle (control), virus alone (LNSV), or virus containing
AT1R-AS (LNSV-AT1R-AS). The
treatments were injected directly into the left ventricle of the heart
under methoxyflurane anesthesia (metofane, Pitmin-Moore).
One bolus of 5x1010 plaque-forming units of
viral particles in 10 µL of physiological saline
was used per animal. There was a 95% survival rate at 24 to 48 hours
after viral administration. Mean blood pressure was measured through an
indwelling catheter implanted in the carotid artery using a Digi-Med
blood pressure analyzer (Micro-Med) essentially as
described.14 All animal protocols are in accordance with
the University of Florida institutional guidelines (IACUC approval 4138
and 5236).
Smooth Muscle Cell Isolation
Renal vascular smooth muscle cells were dissociated as
previously described.14 20 Male rats were killed by
decapitation, and the right and left kidneys were removed and placed in
cold oxygenated (95% O2-5%
CO2) physiological saline
solution (PSS). Renal resistance arterioles were identified as the
fifth to sixth branch distal to the renal artery, cut into small
pieces, and subsequently resuspended in Ca2+-free
PSS digestion buffer for 20 to 30 minutes at 37°C. The
Ca2+-free PSS digestion buffer contained (in
mg/15 mL) collagenase (151 U/mg Worthington Biochemical
Corp) 4.5, bovine serum albumin (BSA) 30, trypsin
inhibitor 30, ATP (sodium salt) 1.7, and protease (type
XXIV, Sigma Chemical Co) 1.5. After the digestion, the pieces were
gently triturated until a large number of elongated smooth muscle cells
were observed. The isolated cells were collected and stored at 4°C
until use.
Current Recording and Analysis
Single cells were voltage-clamped, and membrane currents were
measured using the whole-cell patch-clamp technique.14 20
Data analysis was performed with pCLAMP 6.0 software (Axon
Instruments). All experiments were performed at room temperature. For
all whole-cell voltage-clamp experiments examining
Ca2+ currents, the bath solution contained
(in mmol/L) CaCl2 1.8, D-glucose
5.5, TEA 5.0, and HEPES 10 (pH 7.4 with CsOH). The pipette solution for
the whole-cell experiments contained (in mmol/L) CsCl 140,
MgCl2 0.5, EGTA 10, ATP (magnesium salt) 5.0, and
HEPES 5.0 (pH 7.2 with CsOH).
Tension Measurements
Rat renal resistance arteriole ring segments (1.5 mm long)
were mounted onto 2 triangular tungsten wires (35 µm in
diameter) and hung vertically in an isolated organ chamber (5 mL) as
previously described.14 The bath was maintained at 37°C
in PSS.
[Ca2+]i Measurement
[Ca2+]i was
measured in dissociated renal resistance arteriolar cells using
epifluorescence microscopy. Briefly, the cells were loaded with
fura 2 by incubation with 5 µmol/L membrane-permeable fura 2
acetoxymethylester (fura 2-AM dissolved in 1 mmol/L DMSO stock)
for 30 minutes at 37°C. The cells were illuminated alternately with
UV light of 340 and 380 nm wavelength using an IonOptix chopper-based,
electronically controlled, dual-excitation imaging fluorescence
system. Cell fluorescence (emitted light) was collected through
a 510-nm barrier filter before acquisition by a photomultiplier tube.
The fluorescence signals, F340 and
F380, were background subtracted during the
experiment. The mean change F340 and
F380 ratios are graphed, which gives a relative
indication in the changes observed in
[Ca2+]i. The
Rmin and Rmax of WKY and
SHR cells treated with and without virus is not significantly
different.
Western Blot Analysis
Renal resistance arterioles were snap-frozen with liquid
nitrogen. To isolate proteins, 0.1 g of tissue was
homogenized in 2.0 mL of cold Tris-HCl buffer containing
2.5 mg/mL leupeptin and 4 mg/mL calpain inhibitors, pH 7.4.
The suspension was centrifuged at 30 000g for 20
minutes at 4°C. The resultant pellet was resuspended in the above
solution and recentrifuged. This pellet was resuspended in
1.2% digitonin, 300 mmol/L KCl, 150 mmol/L NaCl, 10
mmol/L NaPO4, pepstatin A (0.1 µg/mL),
leupeptin (0.1 µg/mL), aprotinin (0.1 µg/mL), AESFB
(0.02 mmol/L), benzamidine (0.01 mg/mL), and calpain (0.8
µg/mL), pH 7.4. The protein concentration in the supernatant was
determined by Bio-Rad assay using BSA for the standard curve.
For immunoblotting, 20 µg protein was denatured with
Laemmli's sample buffer in a boiling water bath for 3 minutes. Each
mixture was electrophoresed in 4% to 15% SDS–polyacrylamide
gel and transferred onto nitrocellulose. The membrane was blocked with
10% nonfat dried milk in PBST-BSA for 1 hour followed by incubation
overnight at 4°C with either anti–ß-actin (1:100, Sigma) or
anti-1C Ca2+ channel
protein (1:1000, Alamone Labs). Protein-bound antibody was detected by
incubation of the membrane with horseradish peroxidase–labeled
secondary antibody (1:50 000, Jackson ImmmunoResearch Laboratory),
enhanced by chemiluminescent assay reagents, and recognized by exposure
to film.
Statistics
Results are expressed as mean±SEM. Statistical significance was
evaluated using repeated-measures ANOVA and Student's t
test for unpaired data. Differences were considered significant at
P<0.05. Membrane currents were measured from the zero
current level and normalized to cell capacitance.
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Results |
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Effect of AT1R-AS Treatment on Blood Pressure
A single intracardiac injection of LNSV-AT1R-AS to neonatal rats prevented the increase in blood pressure exclusively in SHR for at least 210 days after injection (Figure 1
). The mean
blood pressure was 36.6% lower in SHR treated with
LNSV-AT1R-AS than in untreated SHR (128±12
versus 202±8 mm Hg, n=6; P<0.01). In addition, the
mean blood pressure measured in
LNSV-AT1R-AS–treated SHR was not significantly
different from that of the normotensive WKY controls (128±12 versus
118±6 mm Hg, n=6; P>0.05). This effect was specific
for LNSV-AT1R-AS treatment since treatment with
LNSV alone had no significant effect on mean blood pressure compared
with that in control SHR (192±7 versus 202±8 mm Hg, n=6;
P>0.05). A nonsignificant 10-mm Hg decrease in blood
pressure was observed in WKY treated with antisense, while LNSV alone
did not significantly affect the blood pressure of WKY (n=6, data not
shown). This decrease in blood pressure is similar to that observed
with acute losartan treatment of WKY.19
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Effect of LNSV-AT1R-AS Treatment on Voltage and
Receptor-Dependent Renal Arteriolar Vascular Reactivity
Alterations in vascular contractile response are known to exist in
SHR, but no one has investigated specifically the role of
[Ca2+]i in small
arterioles of the kidney, which play a significant role in regulating
peripheral resistance.1
LNSV-AT1R-AS treatment prevented the alterations
in voltage- and receptor-dependent renal arteriolar vascular reactivity
measured in SHR (Figure 2). Enhanced
contractile responses to both KCl (Figure 2A) and Ang II (Figure 2C) were observed in the SHR. A significant leftward shift in
the KCl and Ang II concentration-response relationships was observed in
SHR when compared with WKY controls (Figure 2A and 2C). The
media effective concentrations (EC50) for KCl and
Ang II were 11.1±2.1 mmol/L and 19.7±2.8 nmol/L (n=24 rings from
6 animals) in the untreated SHR and 36.6±3.4 mmol/L and 76.4±3.3
nmol/L (n=24 rings from 6 animals) in the WKY, respectively.
LNSV-AT1R-AS prevented the shift in the
EC50 for both KCl and Ang II (Figure 2B and 2D). The EC50 for KCl and Ang II in the
LNSV-AT1R-AS–treated SHR was 39.1±4.2
mmol/L and 68.7±4.2 nmol/L (n=24 rings from 6 animals), which was not
significantly different from that of the WKY. Finally the
EC50 for KCl and Ang II in the LNSV-treated SHR
was 21.1±3.8 mmol/L and 17.7±2.1 nmol/L (n=24 rings from 6
animals), which was not significantly different from that of the
untreated SHR.
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Effect of LNSV-AT1R-AS on L-Type Ca2+
Current Density
It has been previously demonstrated that L-type
Ca2+ current is increased in large conduit
arteries of the SHR.15 Figure 3 illustrates the characteristics of
L-type Ca2+ current in single cells isolated from
renal resistance vessels of WKY and SHR. During voltage step
depolarizations in the presence of blockers of K+
current, an inward Ca2+ current was observed.
This Ca2+ current was L-type because it is
completely inhibited by the dihydropyridine
nifedipine (100 nmol/L, data not shown). It is quite
evident from the current recordings (Figure 3A) and the
current-voltage relationships (Figure 3B, n=21 cells from 6
animals) that Ca2+ current density in the cells
from the SHR was increased when compared with cells from the WKY. This
increase in Ca2+ current was not evident in SHR
treated with LNSV-AT1R-AS but was apparent in
those treated with LNSV alone (Figure 3A and 3B).
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A number of reasons for the difference in Ca2+
current may exist. First, this difference in Ca2+
current density could be due a difference in cell size. It should be
noted that the cell capacitance was not significantly different among
all of the groups tested (WKY 28±3 pF, SHR 27±2 pF,
SHR-LNSV-AT1R-AS 29±2 pF, SHR-LNSV 26±3 pF).
Second, the difference in Ca2+ current density
may be due to alterations in the properties of voltage-dependent
activation or inactivation. However, the
Table illustrates that when the
activation or inactivation curves for the Ca2+
current were fit with a Boltzmann function, membrane potential at which
one-half activation or inactivation (V1/2) or the
slope of the Boltzmann function was unaffected in cells from the WKY,
SHR, SHR+LNSV, or SHR+AT1R-AS. Finally, we
examined whether there was an increase in Ca2+
channel protein density in the renal vasculature of the SHR. Western
blot analysis (Figure 4) using an
antibody that recognized 1C
Ca2+ channel proteins illustrated that when
normalized to ß-actin, there was no increase in the number of L-type
Ca2+ channels in the SHR renal resistance
arterioles when compared with those in the WKY. Administration of
LNSV-AT1R-AS did not alter these data.
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Effect of LNSV-AT1R-AS on Voltage- and
Receptor-Dependent Changes in [Ca2+]i
Because the KCl and Ang II concentration-response relationship was
shifted to the left in the SHR and this was prevented in the SHR
treated with LNSV-AT1R-AS, we wanted to examine next whether
alterations in intracellular Ca2+ handling would
be prevented using LNSV-AT1R-AS gene therapy. We
have previously shown that basal and Ang II–stimulated increases in
[Ca2+]i were greater in
renal arteriolar cells of the SHR when compared with
WKY.17 Figure 5 shows the
change in [Ca2+]i when
renal resistance artery cells were challenged with KCl (30 mmol/L,
Figure
[fig+5]5A) or Ang II (30 nmol/L, Figure [fig+5]5B). These
doses were chosen because they are approximately 50% effective. Both
KCl and Ang II significantly increased
[Ca2+]i in renal
arteriolar cells of the SHR when compared with WKY cells (n=162 cells
from 4 animals). These increases in
[Ca2+]i were completely
prevented when SHR were treated with LNSV-AT1R-AS
(n=134 cells from 4 animals). There was no significant difference
between SHR+LNSV and the untreated SHR (n=122 cells from 4 animals).
When experiments were performed in zero external calcium, all of the
KCl-dependent contractions were abolished. However, Ang II still
produced a greater peak
[Ca2+]i measurement in
renal arteriolar cells from the SHR than from the WKY. These increases
in [Ca2+]i were
completely prevented when SHR were treated with
LNSV-AT1R-AS (data not shown). These data support
the conclusion that LNSV-AT1R-AS gene therapy
prevents altered Ca2+ handling in
hypertension.
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Discussion |
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The results of this study are novel and demonstrate for the first time that the delivery of AT1R-AS prevents (1) the development of hypertension for up to 210 days and (2) the alterations in [Ca2+]i homeostasis associated with hypertension in the SHR. Neonatal SHR that were given a single intracardiac injection of AT1R-AS did not develop (1) elevated blood pressure; (2) increased voltage-dependent Ca2+ influx, as measured by an increase in Ca2+ current density, across renal vascular smooth muscle membranes; (3) an increase in Ang II–mediated Ca2+ influx; or (4) increased Ca2+ release from sarcoplasmic reticulum. These findings, along with our previous observations,14 suggest that interruption of the RAS with virally mediated gene delivery may be used to prevent hypertension and its associated renal pathophysiological complications.
The kidneys, which exquisitely control blood pressure and extracellular fluid volume and ultimately renal blood flow, participate in the development of essential hypertension. The results of earlier renal transplant studies in humans and animals suggest that in a proportion of hypertension cases there exist structural or functional alterations in the kidney.16 An elevation in renal vascular tone and therefore renal vascular resistance exists in hypertension; this elevation may be due to a number of factors including (1) an enhanced contractile sensitivity to vasoactive agonists, (2) an impaired endothelium-dependent relaxation, (3) an increased Ca2+ transport across vascular smooth muscle membranes, (4) an altered ion channel activity in vascular smooth muscle, and (5) smooth muscle hypertrophy or hyperplasia.1
One fundamental reason why renal vascular resistance may be increased in hypertension is an altered ion channel function in vascular smooth muscle cells. Tonic changes in membrane potential and thus Ca2+ influx regulate contractile tone of resistance arterioles. A number of reports show that Ca2+ current density is increased in the SHR model of hypertension.15 However, these studies have been in conduit arteries, which play a less significant role in the regulation of peripheral resistance. Here we show that not only is Ca2+ current density increased in the SHR, but there is no change in the level of Ca2+ channel protein in renal resistance vessels. These data suggest that there may be an altered intracellular regulation of L-type Ca2+ channels that may underlie the enhanced Ca2+ influx in vascular smooth muscle cells and increases in vascular resistance observed in the kidney in hypertension. It is possible that an increase in Ca2+ influx could tend to load the sarcoplasmic reticulum with more Ca2+, enabling more to be released on challenge by a physiological stimuli. Here we show that this altered Ca2+ handling by the sarcoplasmic reticulum can be prevented using AT1R-AS. This prevention would underlie the shift of the concentration-response curve back to normal with AT1R-AS treatment. Physiologically, this would tend to decrease the amount of vascular tone in the kidney for a given concentration of circulating Ang II.
Finally, cardiovascular ultrastructural changes are a major risk factor for morbidity and mortality in hypertension, and Ang II has been speculated to play a role in the increased vascular hypertrophy and/or hyperplasia in hypertension. Could gene therapy delivery systems interrupting the RAS be used to control the vascular remodeling/hypertrophy seen in various forms of hypertension? We have previously shown that AT1R-AS treatment could prevent the observed increase in perivascular fibrosis and ventricular hypertrophy in the SHR.14 Liao et al21 have demonstrated that receptor-dependent stimulation of a Ca2+-dependent PKC isoform activates mitogen-activated protein kinase (MAPK) and thus regulates vascular smooth muscle cell growth. The above associated complications occur on a long-term basis, and their cellular mechanisms of action appear to be a [Ca2+]i-dependent process. Therefore, interference in the RAS using gene therapy may be an important pharmacological target to block vascular ultrastructural and remodeling changes in hypertension.
Is antisense gene therapy targeting the RAS a therapeutic step forward? In short, the answer is yes. It results in the prevention of the increase in mean blood pressure and the associated pathophysiological impairments in hypertension. It also offers an alternative to the compliance problem and complications of vascular and target-organ injury. Finally, AT1R-AS therapy does not produce a significant increase in plasma Ang II levels compared with losartan, the AT1R antagonist.18 Therefore, AT1R-AS gene delivery and therapy does have prolonged antihypertensive effects without the possible adverse side effects produced by traditional pharmacological therapies. One caveat of the approach taken in this study is that AT1R-AS gene delivery prevents the pathophysiological complications occurring with the development of hypertension. Moreover, this type of gene delivery/therapy depends on the identification of genetic determinants of hypertension or on the demonstration of reliable prehypertensive risk factors before it can be used in human trials. Another approach currently being investigated in our laboratory is to develop the next generation of viral vectors, which would increase the feasibility of delivering RAS-relevant genes into the adult SHR to reverse pathophysiological complications observed in hypertension. Preliminary studies show that delivery of RAS-relevant antisense into the adult SHR reverses the increase in blood pressure as well as the differences in excitation-contraction coupling observed in hypertension (C.H. Gelband, unpublished observations, 1998). In summary, gene therapy holds promise in single-dose, long-term treatment for hypertension.
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Acknowledgments |
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This work was supported by grants from the National Institutes of Health (HL-52189 to C.H.G.) and (HL-56921 to M.K.R.), the Council for Tobacco Research (to C.H.G.), and the American Heart Association, Florida Affiliate (postdoctoral and predoctoral fellowships to P.Y.R. and J.E., respectively). We would like to thank Rebecca Kocerha for technical assistance.
Received September 15, 1998; first decision October 15, 1998; accepted October 29, 1998.
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References |
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1. Khalil RA, Lodge NJ, Gelband CH, van Breemen C. In: Laragh JH, Brenner BM, eds. Hypertension: Pathophysiology, Diagnosis, and Management. New York, NY: Raven Press Publishers; 1990:547–567.
2. Whelton PK. Epidemiology of hypertension. Lancet. 1994;334:101–106.
3.
Stamler J, Stamler R, Neaton JD. Blood pressure,
systolic and diastolic and
cardiovascular risks: US population data. Arch
Intern Med. 1993;153:598–615.
4. Kang PM, Landau AJ, Eberhardt RT, Fishman WH. Angiotensin II receptor antagonists: a new approach to blockade of renin angiotensin system. Am Heart J. 1994;127:1388–1401.[Medline] [Order article via Infotrieve]
5. Hsueh WA, Do Y-S, Anderson PW, Law RE. Angiotensin II in cell growth and matrix production. In: Mukhopadhyay A, Raizada MK, eds. Tissue Renin-Angiotensin System. New York, NY: Plenum Press; 1995:217–223.
6. Brunner HR, Nussberger J, Waeber B. Angiotensin II blockade compared with other methods of inhibiting the renin-angiotensin system. J Hypertens. 1993;11:553–558.
7. Kurtz TW, Simonet L, Kabra PN, Wolfe S, Chen L, Hjelle BL. Cosegregation of the renin allele of the spontaneously hypertensive rat with an increase in blood pressure. J Clin Invest. 1990;85:1328–1332.
8. Jeunemaitre X, Soubrier F, Kotelevtsev YV, Lifton RP, Williams CS, Charru A, Hunt SC, Hopkins PN, Williams RR, Label JM, Corvol P. Molecular basis of human hypertension: role of angiotensinogen. Cell. 1992;71:169–180.[Medline] [Order article via Infotrieve]
9.
Bonnardeaux A, Davies E, Jeunemaitre X, Fery I, Charru
A, Clauser E, Tiret L, Cambien F, Corvol P, Soubrier F.
Angiotensin II type 1 receptor gene polymorphism in
human essential hypertension. Hypertension. 1994;24:63–69.
10. Kaneko K, Susic D, Nunez E, Frohlich ED. Losartan reduces cardiac mass and improves coronary flow reserves in the spontaneously hypertensive rat. J Hypertens. 1996;14:645–653.[Medline] [Order article via Infotrieve]
11. Vogt M, Motz WH, Schwartzkopf B, Strauer BE. Pathophysiology and clinical aspects of hypertensive hypertrophy. Eur Heart J. 1993;14:2–7.
12.
Olivero MI, Best CF, Kim HS, Arendshorst WJ, Smithies
O, Coffman TM. Angiotensin II responses in
AT1A receptor-deficient mice: a role for
AT1B receptors in blood pressure regulation.
Am J Physiol. 1997;272:F515–F520.
13.
Phillips ML, Mohuczy-Dominiak D, Coffey M, Galli SM,
Kimura PW, Zelles T. Prolonged reduction of high blood pressure with an
in vivo, nonpathogenic, adenoassociated viral vector delivery of
AT1-R mRNA antisense. Hypertension. 1997;29:374–380.
14.
Martens JR, Reaves PY, Lu D, Berecek KH, Bishop SP,
Katovich MJ, Raizada MK, Gelband CH. Prevention of cardiac and
renovascular pathophysiological changes in
hypertension by AT1 receptor antisense gene
therapy. Proc Natl Acad Sci U S A.. 1998;95:2664–2669.
15. Martens JR, Gelband CH. Ion channels in vascular smooth muscle: alterations in essential hypertension. Proc Soc Exp Biol Med. 1998;218:192–203.[Medline] [Order article via Infotrieve]
16. Curtis J, Luke R, Dustan H, Kashgarian M, Whelchel J. Remission of essential hypertension after renal transplantation. N Engl J Med. 1983;309:1009–1015.[Abstract]
17.
Iyer SN, Lu D, Katovich MJ, Raizada MK. Chronic
control of high blood pressure in the spontaneously hypertensive rat by
delivery of angiotensin type 1 receptor antisense.
Proc Natl Acad Sci U S A. 1996;93:9960–9965.
18.
Lu D, Yang H, Raizada MK. Attenuation of ANG II actions
by adenovirus delivery of AT1 receptor antisense
in neurons and SMC. Am J Physiol. 1998;274:H719–H727.
19.
Lu D, Raizada MK, Iyer S, Reaves P, Yang H, Katovich
MJ. Losartan versus gene therapy: chronic control of high blood
pressure in spontaneously hypertensive rats. Hypertension. 1997;30:363–370.
20.
Martens JR, Gelband CH. Alterations in rat interlobar
artery membrane potential and K+ channels in
hypertension. Circ Res.. 1996;79:295–301.
21.
Liao DF, Duff JL, Daum G, Pelech SL, Berk BC.
Angiotensin II stimulates MAP kinase kinase kinase activity
in vascular smooth muscle cells. Circ Res. 1996;79:1007–1014.
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C. H. Gelband, H. Wang, M. L. Gardon, K. Keene, D. S. Goldberg, P. Y. Reaves, M. J. Katovich, and M. K. Raizada Angiotensin I-Converting Enzyme Antisense Prevents Altered Renal Vascular Reactivity, but Not High Blood Pressure, in Spontaneously Hypertensive Rats Hypertension, January 1, 2000; 35(1): 209 - 213. [Abstract] [Full Text] [PDF]
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 P. Sinnaeve, O. Varenne, D. Collen, and S. Janssens Gene therapy in the cardiovascular system: an update Cardiovasc Res, December 1, 1999; 44(3): 498 - 506. [Abstract] [Full Text] [PDF]
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P. Y. Reaves, C. H. Gelband, H. Wang, H. Yang, D. Lu, K. H. Berecek, M. J. Katovich, and M. K. Raizada Permanent Cardiovascular Protection From Hypertension by the AT1 Receptor Antisense Gene Therapy in Hypertensive Rat Offspring Circ. Res., November 12, 1999; 85 (10): e44 - e50. [Abstract] [Full Text] [PDF]
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 J. Zicha and J. Kunes Ontogenetic Aspects of Hypertension Development: Analysis in the Rat Physiol Rev, October 1, 1999; 79(4): 1227 - 1282. [Abstract] [Full Text] [PDF]
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 M. J. Katovich, C. H. Gelband, P. Reaves, H.-W. Wang, and M. K. Raizada Reversal of hypertension by angiotensin II type 1 receptor antisense gene therapy in the adult SHR Am J Physiol Heart Circ Physiol, September 1, 1999; 277(3): H1260 - H1264. [Abstract] [Full Text] [PDF]
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M. K. Raizada, M. J. Katovich, H. Wang, K. H. Berecek, and C. H. Gelband Is antisense gene therapy a step in the right direction in the control of hypertension? Am J Physiol Heart Circ Physiol, August 1, 1999; 277(2): H423 - H432. [Full Text] [PDF]
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