Hypertension. 2000;35:568-573
(Hypertension. 2000;35:568.)
© 2000 American Heart Association, Inc.
Contribution of Autosomal Loci and the Y Chromosome to the Stress Response in Rats
Pierre Dumas;
Zdenka Pausová;
Vladimír Kren;
Drahomíra Krenová;
Michal Pravenec;
Marc Dumont;
Daniel Ely;
Monte Turner;
Yulin Sun;
Johanne Tremblay;
Pavel Hamet
From the Centre de Recherche du CHUM, Université de
Montréal, Montréal, Québec, Canada (P.D., Z.P., M.D.,
Y.S., J.T., P.H.); the Institute of Biology, First Medical Faculty, Charles
University, Prague, Czech Republic (V.K., D.K., M.P.); the Institute of
Physiology, Czech Academy of Sciences, Prague, Czech Republic (V.K., M.P.);
and the Department of Biology, University of Akron, Akron, Ohio (D.E., M.T.).
Correspondence to Johanne Tremblay or Pavel Hamet, Laboratory of Cellular Biology of Hypertension and Laboratory of Molecular Medicine, Centre de Recherche-CHUM, 3850 Rue Saint-Urbain, Montréal, Québec, Canada H2W 1T8. E-mail hamet{at}ere.umontreal.ca
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Abstract
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AbstractStress is a critical
contributor to cardiovascular
diseases through its
impact on blood pressure variability and
cardiac function. Familial
clustering of reactivity to stress
has been demonstrated in human
subjects, and some rodent models
of hypertension are hyperresponsive to
stress. Therefore, the
present study was designed to uncover the
genetic determinants
of the stress response. We performed a total
genome linkage
search to identify the loci of the body temperature
response
to immobilization stress in a set of recombinant inbred
strains
(RIS) originating from reciprocal crosses of spontaneously
hypertensive
rats (SHR) with a normotensive Brown Norway Lx
strain. Two
quantitative trait loci (QTLs) were revealed on chromosomes
(Chrs) 10 and 12 (logarithm of odds scores, 2.2 and 1.3,
respectively).
The effects of these QTLs were enhanced by a high
sodium diet
(logarithm of odds scores, 4.0 and 3.3 for Chrs 10
and 12,
respectively), which is suggestive of a salt-sensitive
component
for the phenotype. Congenics for Chr 10 confirmed
both the
QTL and the salt effect in RIS. Negatively associated loci
were
also identified on Chrs 8 and 11. Interaction between the loci
of
Chrs 10 and 12 was demonstrated, with the rat strains bearing
SHR
alleles at both loci having the highest thermal response
to stress.
Furthermore, the Y Chr of SHR origin enhanced the
response to
immobilization stress, as demonstrated in 2 independent
models,
RIS and Y Chr consomics. However, its full effect requires
autosomes of
the SHR strain. These findings provide the first
evidence for the
genetic determination of reactivity to stress
with interactions between
autosomal loci and between the Y
and autosomal Chrs that contribute to
the explanation of the
46% of variance in the stress response.
Key Words: stress linkage (genetic) quantitative trait sex chromosomes
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Introduction
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The response to environmental stress is a predictor of
cardiovascular
diseases, including future high blood
pressure (BP), in prehypertensive
patients with a positive family
history
1 and the development
of left
ventricular hypertrophy.
2
Spontaneously hypertensive
rats (SHR) and mice are more reactive to
stress than their
normotensive counterparts.
3 4 5 6 On
exposure to several psychogenic
stressors, such as cage-switch,
placement in an open field,
or immobilization, they display higher
changes in heart rate,
BP, and body temperature (BT).
5 7
The increase in BT with
immobilization stress may, thus, be proposed as
an intermediate
phenotype of the stress response. To identify
the genetic determinants
of the BT response to immobilization stress,
we performed a
full genome scan in a set of rat recombinant inbred
strains
(RIS) originating from reciprocal crosses of SHR and
normotensive
Brown Norway (BN) Lx strains. This is the only set
of rat RIS
available to study the genetics of hypertension and its
related
traits.
8 Any quantitative phenotype that
can be measured accurately
and that displays a significant gradient
across strains can
be mapped in the RIS panel, irrespective of the
differences
between progenitor strains,
9 in this permanent
replica of
the F
2 generation rendered
homozygous by over 30 generations
of inbreeding. Therefore, we used
this paradigm to identify
quantitative trait loci (QTL) of the stress
response variance
with increased BT after immobilization as a
phenotype. Because
our previous data indicated that high sodium
intake heightens
the response to immobilization stress,
10
we measured BT in
rats fed normal and high sodium diets.
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Methods
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Rats
Male rats weighing 150 to 300 g were studied. RIS
reciprocal
crosses were derived from SHR/Ola and BN.Lx/Cub
strains, as
described previously.
8 BN.Lx rats are congenic
rats carrying
a segment of chromosome (Chr) 8 from polydactylous
(PD)/Cub
strains.
11 They are genetically distant
from SHR and were
thus chosen for the breeding and development of
segregating
strains because more polymorphic markers can be found
between
the 2 strains.
8 Experiments were performed during
4 separate
time periods in both Prague and Montreal, which enabled us
to
test many of the strains twice under both dietary conditions
to
confirm the phenotypic values obtained. The rats were maintained
on a
12-hour day/night cycle at a room temperature of 23 to
25°C. They
were given access to water and food ad libitum,
and the protocols of
the study were approved by the local animal
care committees.
A total of 27 RIS were used for stress-response phenotyping. The high
Na diet consisted of normal rat chow (0.6% Na) supplemented with NaCl
to raise the Na content to 3.15% by weight (8% NaCl). Y Chr consomic
strains, originally designated as SHR/y and SHR/a, were developed from
Wistar-Kyoto (WKY) and SHR inbred colonies kept at the
University of Akron, Ohio, as described previously.12 For
uniformity of nomenclature, we designated them here as WKY.SHR-Y and
SHR.WKY-Y, respectively, according to their somatic and sexual Chr
origins.
The SHR.BN-Y consomic strain was produced by introgressing the Y Chr
from BN males into the SHR genetic background (V. Kren, DSc, et al,
unpublished data, 1998). The BN Y Chr is cytogenetically
distinguishable from the Y Chr of SHR origin (M. Sladká, oral
communication, 1998). SHR.BN-Rattus norvegicus Chr 10
(RNo10) congenics were obtained by introgressing a segment of BN Chr 10
onto the SHR genetic background. After 9 backcrosses, an intercross was
performed, and Myh3 BB homozygotes were
selected by polymerase chain reaction genotyping. Myh3
BBhomozygous congenic males from N9F3 with residual
heterozygosity in Myh3 flanking markers were used.
D10Wox11, D10Mit4, and D10Rat31
markers were BB homozygotes. Residual heterozygosity was observed for
the following Myh3 flanking markers: D10Wox12,
D10Wox14, D10Mit2, D10 Mgh6,
D10Rat59, and D10Rat102. D10Mit1/Ace,
D10Mit5, and D10Mit7 were HH homozygotes (D.
Krenova, DSc, et al, unpublished results, 1998). A total of 2 to
12 rats per RIS were used for phenotyping. For congenic and consomic
strains, 6 to 9 rats were used (see Figures).
Thermal Response to Stress
BT after immobilization served as a reproducible marker of the
stress response. To control the variation of the circadian rhythm of
BT, all measurements were conducted between 8:00 and 12:00
AM in a calm environment. Naive animals were placed in
transparent plastic restraint holders routinely used for tail-cuff
determination of BP in rats, and a rectal thermal probe was introduced
(3 to 5 cm) rapidly and secured around the tail. Rectal temperature was
monitored continuously during the 20-minute immobilization period
(T20). Two rats could be recorded simultaneously, with
randomization of temperature probes and strains. Temperature
thermistors with a linearity between 5 and 45°C and a precision of
0.1°C were used (YSI 44202, Yellow Springs Instrument Co).
Genetic Analysis
The heritability of T20 under both dietary conditions was
estimated using the following formula: heritability=Va/(Va+Ve), where
Va is the interstrain variance and Ve, the intrastrain variance. Strain
distribution patterns of the thermal response to stress observed on
high and normal Na diets were correlated with those of 475 biochemical,
morphological, immunogenetic, and molecular genetic markers available
from the ratmap Internet site.13 The nomenclature
and descriptions are reported in detail elsewhere.9 14 The
linkage map of RIS covers 1139 centimorgans (cM) of the rat genome,
with a mean of 20 markers per Chr, as described
previously.14
Total Genome Linkage Search
Linkage analysis was performed with MapManager software,
which was developed and adapted by Dr K.F. Manly for QTL
analysis (MapManager QT v3.0b21).15 16 Because of
multiple simultaneous comparisons, stringent statistical
criteria were used to avoid false-positive linkages.9 We
ran a nonparametric permutation test, as proposed by Doerge
and Churchill17 and implemented on MapManager, which
estimates thresholds of findings specified by linkage statistics on
total genome scan. The thresholds used were 0.5, 0.05, and 0.001, which
corresponded to suggestive, significant, and highly significant
linkages, respectively.18 The permutation test was run for
each phenotype every 5 cM with 500 permutations to simulate the
experimental conditions of marker density and multiple comparisons
required, respectively. Pearson product-moment correlation
analysis, which is equivalent to the Holms t-test,
was also used. It provided signs of association and an estimate of the
percentage of variance of the trait explained by the locus
(r2).
Statistics
Data are presented as the mean±SEM obtained for a
single measurement in several animals, as indicated in Results. We
evaluated the relative contribution of each significant locus with a
multiple linear regression model. The dependent variable was T20,
and the independent predictors were the individual significant loci
taken as dichotomous variables (-1 for BN.Lx genotypes; 1
for SHR genotypes). The diet effect was also studied (-1 for
normal diet; 1 for the high-salt diet). All analyses were
considered significant at the 0.05
level. Data from individual rats
were computed.
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Results
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Although the basal BT of SHR and BN.Lx strains was identical,
immobilization stress for 20 minutes induced a greater thermal
response
in SHR compared with BN.Lx, as illustrated by a higher
temperature and
a higher rate of BT increase (Figure 1
).
Rectal
temperature at T20 served as the quantitative variable
because
it was the time of maximal response and the point where the
most robust phenotypic difference between the 2 strains could
be
observed (Figure 1
).
7 We, therefore, sought to look
for
specific genetic determinants of the stress response using RIS
originating from reciprocal crosses of BN.Lx and SHR. In this
RIS set,
the strain distribution patterns of BT reached at
T20 as measured under
both normal and high Na intake was a
continuum, indicating the
polygenic nature of these phenotypes,
with a high correlation
between the 2 diets (
r=0.83;
P<0.0001;
Figure 2
). The progenitor strains, BN.Lx and
SHR, did not stand
at the extremes of distribution, which indicates
that alleles
increasing or decreasing the stress response could be
found
in both progenitor strains, which is suggestive of loci
interaction.
Figure 2
illustrates that the degree of genetic
variance (interstrain
variance) largely exceeded the intrastrain
variance attributable
to the environment, underlying the predominance
of genetic
contribution to the trait. The heritability of T20 (which
includes
a shared environment) was estimated at 72% and 66% under
normal
and high Na intake, respectively. This phenotype was
selected
because it has a high heritability compared with
phenotypes
involving initial temperature, such as change in
temperature
(

T), and initial rate of increase, for which
heritability
was 59% and 49%, respectively.

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Figure 1. BT during immobilization stress in BN.Lx and SHR
strains. Values are mean±SEM. P<0.05 by ANOVA; n=8 and
n=5 for BN.Lx and SHR, respectively.
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Figure 2. a, Strain distribution pattern for T20 (mean±SEM)
measured under normal Na intake in 25 RIS. b, Strain distribution
pattern of T20 measured under high Na intake in 24 RIS. White bars
indicate BN.Lx and SHR progenitor strains. BxH are strains originating
from crosses of female BN.Lx and male SHR, whereas HxB are strains
originating from crosses of female SHR and male BN.Lx. Shown within
bars are number of rats used per strain.
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Total Genome Linkage Search
The T20 phenotype was measured in 25 strains on a normal
salt diet and in 24 strains on a high-salt diet. This analysis
showed 2 QTLs on Chrs 10 and 12 (Figure 3) that were significantly
associated with the T20 phenotype. The most significant
association was found on Chr 10 (Myh3; r=0.58;
P=0.0017; logarithm of odds [LOD] score, 2.2; Figure 3a). This effect had greater significance when the stress
response was measured in rats fed a high Na diet (r=0.72;
P=0.00002; LOD score, 4.0). The effect of this QTL explains
the 34% and 52% of the T20 variance on normal and high Na intakes,
respectively.

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Figure 3. QTL plot for T20 measured in 21 RIS under normal
and high Na intake. Dotted line indicates significance threshold
according to permutation test. The 95% confidence intervals (CI) were
calculated according to the method of Darvasi and Soller19
using the following formula:
CI=530/(nxr2), where n=49 strains
and r2=proportion of variance
explained. Data (strains) from both conditions were combined. a, Chr
10. Partial linkage map from Dcp1 to Mit4 from Pravenec et
al14 Chr designation (D10) is omitted. CI=26 cM. b, Chr
12. Partial linkage map from Cebr6s4 to Mit8 from Pravenec et
al13 Chr designation (D12) is omitted. CI=33 cM.
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Another QTL was found on Chr 12, with a peak at the Lsn2
marker (r=0.49; P=0.014; LOD, 1.5; Figure 3b). Its effect on T20 was increased by high Na intake
(r=0.69; P=0.000094; LOD, 3.3). The statistical
significance of these results satisfied the stringent statistical
criteria proposed by Neumann20 that are required for
genome scan when using RIS.
Impact of Chr 10 QTL on the Stress Response: RNo10 Congenic
Strain
Chr 10 (RNo10) congenic rats were used to further assess the
impact of the locus identified in RIS. Figure 4a shows the size of the segment of BN
Chr 10 transferred onto a SHR genetic background. On both normal and
high Na diets, SHR.BN-RNo10 congenic rats displayed a lower T20 than
SHR (Figure 4b). In accordance with the results obtained with
the genome scan in RIS, the observed difference between SHR.BN-RNo10
and SHR had a greater significance with high Na intake (Figure 4b). Furthermore, the congenic paradigm narrowed down the region
impacting on T20.

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Figure 4. Impact of BB
genotype at Myh3 marker on stress response for
SHR.BN-RNo10 congenic strain. a, Characterization of RNo10 segment of
BN transferred to SHR in SHR.BN-RNo10 congenics studied. Markers
D10Mit4, D10Wox12,
D10Rat31, D10Wox11, and
Myh3 were homozygous to BB in all rats studied.
D10Mit7, D10Mit5, and
D10Mit1 (Ace) were of HH
genotype, and residual heterogeneity was found
in D10Wox14 (D10Mgh22),
D10Mgh6, D10Mit2, and
D10Rat59. White bar denotes region of BB homozygosity,
whereas black bars denote background HH homozygosity. Gray bars are
regions where heterozygosity was found or cannot be excluded. b, Impact
of BB genotype at Myh3 marker on thermal stress
response. SHR.BN-RNo10 indicates congenic rats bearing segment of BN
Chr 10 that is homozygous for BB at Myh3 marker on SHR
genetic background. P=0.03 and P=0.007
when stress is measured under normal and high Na diets,
respectively, compared with SHR (t-test; n=6 and n=8
under normal Na and n=6 and n=9 under high Na for SHR and congenics,
respectively).
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Negatively Correlated QTLs
Negatively correlated QTLs (ie, where BN alleles are
associated with a higher T20 value) were also found when the stress
response was measured in rats under normal Na intake. The most
suggestive one was identified on Chr 11, with a peak at the
Mit2 marker (P=0.0008; LOD, 2.5;
r=-0.65). Another negative QTL for T20 on normal diet was
on Chr 8 by the Cebr92s2 marker (P=0.0046; LOD,
1.9; r=-0.55). Interestingly, a locus for hyperactivity in
the WKHA rat has been localized in the same
region.21
Consomic Strains for the Y Chr: Modulation of the Stress
Response
Because the set of RIS used in this work originates from
reciprocal crosses of BN.Lx and SHR,8 11 we could evaluate
the putative effect of the Y Chr of SHR origin on the stress response.
Strains fed a normal Na diet and bearing the Y Chr of the SHR
progenitor (BxH strains) had a higher T20 than strains bearing the Y
Chr from the BN.Lx progenitor (HxB strains) (Figure 5a; P=0.02). To further
analyze this effect, we studied Y Chr consomic strains on the
normal Na diet. The transfer of the BN Y Chr to a SHR genetic
background in SHR.BN-Y consomics significantly lowered T20 compared
with SHR (38.40±0.29°C versus 39.00±0.16°C, respectively;
P<0.05; Figure 5b). Similarly, in Y Chr consomic
strains originating from WKY and SHR reciprocal
crosses,22 23 T20 was significantly lower in
SHR.WKY-Y strains, which bear the Y Chr from WKY and the autosomes of
SHR, than in SHR (38.64±0.21°C versus 39.15±0.07°C;
P=0.014; Figure 5b). It is noteworthy that the
removal of SHR-Y and its replacement with either BN-Y or WKY-Y produces
a similar decrease in T20. However, transfer of the Y Chr from SHR
(SHR-Y) to a WKY genetic background (in WKY.SHR-Y) did not
increase T20 compared with WKY (38.34±0.19°C versus 38.49±0.24°C;
P=NS). Therefore, it seems that removing SHR-Y from the SHR
background has more impact than adding it to a WKY background, which
suggests that SHR-Y is needed, but not sufficient for, the expression
of the stress response observed in SHR. The Y Chr thus seems to have a
modulating effect on autosomal QTLs of the stress response.

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Figure 5. a, Impact of Y Chr on stress response in RIS. HxB
indicates strains bearing Y Chr from normotensive BN.Lx progenitor
(n=16 RIS). BxH indicates strains bearing Y Chr from hypertensive SHR
progenitor (n=9 RIS). BN.Lx (n=7 rats) and SHR (n=5 rats) strains are
included for comparison. b, Impact of Y Chr on stress response in
WKY.SHR-Y and SHR.WKY-Y consomic strains. F=5.57 and
P=0.0082 by ANOVA.
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Relative Contribution of Significant QTLs on T20
We evaluated the relative contribution of significant QTLs on T20
by multiple linear regression analysis. Two significant markers
were chosen as predictors of T20 (Myh3 on Chr 10 and
Lsn2 on Chr 12), as was the Y Chr, because the impact of the
latter on T20 has been confirmed in consomic strains. Data from
individual rats were computed to increase the power of
analysis, and the effect of the diet was evaluated. Due to
multicolinearity between the primary effects and their interactions,
the model cannot evaluate the impact of diet as an independent
variable. We could, nevertheless, estimate the impact of the high
Na diet by comparing a subset of 209 rats (21 RIS) for which stress was
measured on normal and high Na diets. We observed a significant overall
diet effect (ANOVA, P=0.022), in accordance with the results
shown in Figure 3, which are suggestive of a salt-sensitive
component of T20 at these loci. By combining the individual data under
both dietary conditions (n=242), the following regression equation was
derived: T20=Int38.694+(0.19xMyh3)+ (0.26xLsn2)+(0.14xMyh3xLsn2)+ (0.13xMyh3xYChr)
in which the adjusted
r2=0.46.
This model predicts 46% of T20 variance. The results from multiple
linear regression clearly demonstrated that the effect of the
significant QTLs was not only additive, but that the 3 loci also
interacted: the locus on Chr 10 with the locus on Chr 12, and the locus
on Chr 10 with the Y Chr. For an interaction to be present,
the effect of 1 locus depends on the genotype of the other
locus.24 This is clearly illustrated in the
Table: the interaction between the loci
of Chrs 10 and 12 in which the highest T20 is seen only occurs when the
SHR alleles at both loci are combined (ANOVA, P<0.0001
versus the 3 other genotypic combinations).
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Table 1. T20 Values Resulting From the Genotypic Combination of
Myh3 (QTL on Chr 10) and Lsn2 (QTL on Chr 12)
Loci: Interaction Between the 2 Loci
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Discussion
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This study revealed 2 QTLs on Chrs 10 and 12 that were
significantly
associated with the BT response to immobilization stress
in
rats. Analysis of the syntenic regions for the rat Chr 10 at
the
Myh3 locus reveals a homology to the human Chr 17p13.1.
An attractive candidate for the thermal response to stress
is
Alox12, a 12-lipoxygenase involved in
leukotriene synthesis
from arachidonic
acid, which has been mapped to this region.
25
Prostaglandins may play a role in the temperature response
to stress in rats because antipyretics can prevent the rise
in BT due
to immobilization.
5 Thus, abnormal
arachidonic
acid metabolism could alter
prostaglandin synthesis. It should
also be mentioned that a
BP QTL was found in F2 rats from a
SHR stroke prone
(SHRSP) and WKY cross on Chr 10 in a segment
encompassing
Myh3.
26 In RIS, no QTL for BP was
detected at
this locus when BP was measured via
intra-arterial catheter
under light gas
anesthesia.
9 BP during immobilization stress
will have to be measured by telemetry to determine if the BP
QTL found
in F2 is the same as the one for T20.
Human Chr 7q21-q22 is syntenic to rat Chr 12 near the Lsn2
locus. A malignant hyperthermia susceptibility locus (Mhs3)
has been linked to this segment of Chr 7q. Malignant hyperthermia is a
pharmacogenetic disease that susceptible individuals develop on
exposure to ether and related anesthetics.27 It is
noteworthy that SHR are also hypersensitive to heat and
ether.3 4 28 Genes of calcium channel subunits and Na
channel subunits mapped on human Chr 7q have been proposed as candidate
genes for malignant hyperthermia.29 30 31 The
Hsp27 stress gene is also a good positional candidate on Chr
12, because we have shown its modulation by SHR-Y.32
Discussion of positional candidates must, however, be tempered by the
size of the estimated confidence intervals (
30 cM) associated with
these QTLs.
Finally, of great interest is the demonstration of interactions between
2 autosomal loci (Chr 10 with Chr 12 loci) and between the Y and
autosomal Chrs (Chrs 10 and Y). Interactions between primary QTLs
should be expected with polygenic phenotypes, such as the
stress response. Hence, the use of different crosses may further help
discriminate between confounding and primary QTLs, because different
genetic backgrounds may reveal or hinder significant linkages.
This work opens the way for finding the genetic determinants of
susceptibility to environmental stressors. Two major QTLs were
detected, with a modulating impact of the Y Chr, as ascertained in
congenic and consomic strains. These results provide the first step
toward a full understanding of the genetic basis of the hyperresponse
to environmental stress and its relevance to
cardiovascular diseases.
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Acknowledgments
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We thank Josée Bédard-Baker for her excellent
secretarial assistance, Ovid Da Silva for editing this manuscript,
and
Dr Howard J. Jacob from the Medical College of Wisconsin,
Dr Nicholas
J. Schork from Harvard University, and Drs Bernard
Brais and Alan Y.
Deng of the Research Center-CHUM for their
helpful comments.
This work was supported by the Medical Research
Council of
Canada (MT-12574, MT-14374, and MT-11463); Pfizer
Canada; the Czech
Republic (GA CR K015/98), within the framework
of a collaborative
agreement between Centre Hospitalier de
lUniversité de
Montréal (CHUM) and the
1st Medical Faculty of Charles
University, Prague; and by the
National Institutes of Health (HL
R01-48072-06 to Dr Ely).
Received August 30, 1999;
first decision September 28, 1999;
accepted October 4, 1999.
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References
|
|---|
-
Widgren BR, Wikstrand J, Berglund G, Andersson OK.
Increased response to physical and mental stress in men with
hypertensive parents. Hypertension. 1992;20:606611.[Abstract/Free Full Text]
-
Spence JD, Bass M, Cameron Robinson H, Cheung H,
Melendez LJ, Malcolm O, Arnold J, Manuck SB. Prospective study of
ambulatory monitoring and echocardiography in
borderline hypertension. Clin Invest Med. 1991;14:241250.[Medline]
[Order article via Infotrieve]
-
McMurtry JP, Wexler BC. Hypersensitivity of
spontaneously hypertensive rats (SHR) to heat, ether, and
immobilization. Endocrinology. 1981;108:17301735.[Abstract]
-
Malo D, Schlager G, Tremblay J, Hamet P.
Thermosensitivity, a possible new locus involved in genetic
hypertension. Hypertension. 1989;14:121128.[Abstract/Free Full Text]
-
Morimoto A, Watanabe T, Morimoto K, Nakamori T,
Murakami N. Possible involvement of prostaglandins in
psychological stress-induced responses in rats. J
Physiol. 1991;443:421429.[Abstract/Free Full Text]
-
Berkey DL, Meeuwsen KW, Barney CC. Measurements of
core temperature in spontaneously hypertensive rats by radiotelemetry.
Am J Physiol. 1990;258:R743R749.[Abstract/Free Full Text]
-
Morley RM, Conn CA, Kluger MJ, Vander AJ. Temperature
regulation in biotelemetered spontaneously hypertensive rats.
Am J Physiol. 1990;258:R1064R1069.[Abstract/Free Full Text]
-
Pravenec M, Klir P, Kren V, Zicha J, Kunes J. An
analysis of spontaneous hypertension in spontaneously
hypertensive rats by means of new recombinant inbred strains.
J Hypertens. 1989;7:217222.[Medline]
[Order article via Infotrieve]
-
Pravenec M, Gauguier D, Schott JJ, Buard J, Kren V,
Bila V, Szirer C, Szirer J, Wang JM, Huang H, St-Lezin E, Spence MA,
Flodman P, Printz M, Lathrop GM, Vergnaud G, Kurtz TW. Mapping of
quantitative trait loci for blood pressure and cardiac mass in the rat
by genome scanning of recombinant inbred strains. J Clin
Invest. 1995;96:19731978.
-
Dumas P, Tremblay J, Hamet P. Stress modulation by
electrolytes in salt-sensitive spontaneously hypertensive rats.
Am J Med Sci. 1994;307(suppl 1):130137.
-
Kren V. Genetics of the polydactyly luxate syndrome in
the Norway rat, Rattus norvegicus. Acta Univ Carol Med
Monogr. 1975;58:1104.
-
Ely DL, Daneshvar H, Turner ME, Johnson ML, Salisbury
RL. The hypertensive Y chromosome elevates blood pressure in
F11 normotensive rats. Hypertension. 1993;21:10711075.[Abstract/Free Full Text]
-
RATMAP. Available at: http://ratmap.gen.gu.se. Accessed
1998.
-
Pravenec M, Gauguier D, Schott JJ, Buard J, Kren
V, Bila V, Szpirer C, Wang JM, Huang H, St-Lezin E, Spence MA, Flodman
P, Pritz M, Lathrop GM, Vergnaud G, Kurtz TW. A genetic linkage map of
the rat derived from recombinant inbred strains. Mamm
Genome. 1996;7:117127.[Medline]
[Order article via Infotrieve]
-
Manly KF. A Macintosh program for storage and
analysis of experimental mapping data. Mamm Genome. 1993;4:303313.[Medline]
[Order article via Infotrieve]
-
Manly KF, Elliott RW. RI Manager, a microcomputer
program for analysis of data from recombinant inbred strains.
Mamm Genome. 1991;1:123126.[Medline]
[Order article via Infotrieve]
-
Doerge RW, Churchill GA. Permutation tests for multiple
loci affecting a quantitative character. Genetics. 1996;142:285294.[Abstract]
-
Kruglyak L, Daly MJ, Reeve-Daly MP, Lander ES.
Parametric and nonparametric linkage
analysis: a unified multipoint approach. Am J Hum
Genet. 1996;58:13481363.
-
Darvasi A, Soller M. A simple method to calculate
resolving power and confidence interval of QTL map location.
Behav Genet. 1997;27:125132.[Medline]
[Order article via Infotrieve]
-
Neumann PE. Inference in linkage analysis of
multifactorial traits using recombinant inbred strains of mice.
Behav Genet. 1992;22:665676.[Medline]
[Order article via Infotrieve]
-
Moisan M-P, Courvoisier H, Bihoreau M-T, Gauguier D,
Hendley ED, Lathrop M, James MR, Mormède P. A major quantitative
trait locus influences hyperactivity in the WKHA rat. Nat
Genet. 1996;14:471473.[Medline]
[Order article via Infotrieve]
-
Ely DL, Turner ME. Hypertension in the spontaneously
hypertensive rat is linked to the Y chromosome.
Hypertension. 1990;16:277281.[Abstract/Free Full Text]
-
Turner ME, Johnson ML, Ely DL. Separate sex-influenced
and genetic components in spontaneously hypertensive rat hypertension.
Hypertension. 1991;17:10971103.[Abstract/Free Full Text]
-
Frankel WN, Schork NJ. Whos afraid of epistasis?
Nat Genet. 1996;14:371373.[Medline]
[Order article via Infotrieve]
-
Yoshimoto T, Arakawa T, Hada T, Yamamoto S, Takahashi
E. Structure and chromosomal localization of human
arachidonate 12-lipoxygenase gene.
J Biol Chem. 1992;267:2480524809.[Abstract/Free Full Text]
-
Jacob HJ, Lindpaintner K, Lincoln SE, Kusumi K, Bunker
RK, Mao YP, Ganten D, Dzau VJ, Lander ES. Genetic mapping of a gene
causing hypertension in the stroke-prone spontaneously hypertensive
rat. Cell. 1991;67:213224.[Medline]
[Order article via Infotrieve]
-
Denborough MA, Forster JFA, Lovell RRH, Maplestone PA,
Villiers JD. Anaesthetic death in a family. Br J
Anaesth. 1962;34:395396.[Abstract/Free Full Text]
-
Malo D, Pang SC, Schlager G, Tremblay J, Hamet P.
Decrease of blood pressure in spontaneously hypertensive mice by heat
treatment. Am J Hypertens. 1990;3:400404.[Medline]
[Order article via Infotrieve]
-
Powers PA, Scherer SW, Tsui L-C, Gregg RG, Hogan
K. Localization of the gene encoding the alpha-2/delta subunit
(CACNL2A) of the human skeletal muscle voltage-dependent
Ca2+ channel to chromosome 7q21q22 by somatic
cell hybrid analysis. Genomics. 1994;19:192193.[Medline]
[Order article via Infotrieve]
-
Iles DE, Lehmann-Horn F, Scherer SW, Tsui LC, Olde
Weghuis D, Suijkerbuijk RF, Heytens L, Mikala G, Schwarts A, Ellis FR,
Stewart AD, Deufel T, Wieringa B. Localization of the gene encoding the
alpha 2/delta-subunits of the L-type voltage-dependent calcium channel
to chromosome 7q and analysis of the segregation of flanking
markers in malignant hyperthermia susceptible families. Hum Mol
Genet. 1994;3:969975.[Abstract/Free Full Text]
-
MacLennan DH, Phillips MS. Malignant hyperthermia.
Science. 1992;256:789794.[Abstract/Free Full Text]
-
Ely D, Caplea A, Dunphy G, Turner M, Takiyyuddin M,
Tremblay J, Hamet P. Interaction of the Y chromosome, heat shock
protein, and sympathetic nervous system. In: McCarty R, Aguilera G,
Sabban E, Kvetnansky R, eds. Stress: Molecular Genetic and
Neurobiological Advances. New York: Gordon and Breach Science
Publishers; 1996:281297.
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