QTL mapping for traits associated with stress neuroendocrine reactivity in rats.

Bastien Llamas, Vincent Contesse, Véronique Guyonnet–Duperat, Hubert Vaudry, Pierre Mormède, Marie-Pierre Moisan
Mamm Genome. 2005-07-01; 16(7): 505-515
DOI: 10.1007/s00335-005-0022-2

Read on PubMed

1. Mamm Genome. 2005 Jul;16(7):505-15.

QTL mapping for traits associated with stress neuroendocrine reactivity in rats.

Llamas B(1), Contesse V, Guyonnet-Duperat V, Vaudry H, Mormède P, Moisan MP.

Author information:
(1)Laboratoire Neurogénétique et Stress, INSERM U471/INRA UMR1243, Université
Victor Segalen Bordeaux 2, Institut François Magendie, Rue Camille Saint Saens,
33077 Bordeaux cedex, France.

In the present study we searched for quantitative trait loci (QTLs) that affect
neuroendocrine stress responses in a 20-min restraint stress paradigm using
Brown-Norway (BN) and Wistar-Kyoto-Hyperactive (WKHA) rats. These strains
differed in their hypothalamic-pituitary-adrenal axis (plasma ACTH and
corticosterone levels, thymus, and adrenal weights) and in their
renin-angiotensin-aldosterone system reactivity (plasma renin activity,
aldosterone concentration). We performed a whole-genome scan on a F2 progeny
derived from a WKHA x BN intercross, which led to the identification of several
QTLs linked to plasma renin activity (Sr6, Sr8, Sr11, and Sr12 on chromosomes
RNO2, 3, 19, and 8, respectively), plasma aldosterone concentration (Sr7 and Sr9
on RNO2 and 5, respectively), and thymus weight (Sr10, Sr13, and Srl4 on RNO5,
10, and 16, respectively). The type 1b angiotensin II receptor gene (Agtrlb) maps
within the confidence intervals of QTLs on RNO2 linked to plasma renin activity
(Sr6, highly significant; LOD = 5.0) and to plasma aldosterone level (Sr7,
suggestive; LOD = 2.0). In vitro studies of angiotensin II-induced release of
aldosterone by adrenal glomerulosa cells revealed a lower receptor potency (log
EC50 = -8.16 +/- 0.11 M) and efficiency (Emax = 453.3 +/- 25.9 pg/3 x 10(4)
cells/24 h) in BN than in WKHA (log EC50 = -10.66 +/- 0.18 M; Emax = 573.1 +/-
15.3 pg/3 x 10(4) cells/24 h). Moreover, differences in Agtr1b mRNA abundance and
sequence reinforce the putative role of the Agtr1b gene in the differential
plasma renin stress reactivity between the two rat strains.

DOI: 10.1007/s00335-005-0022-2
PMID: 16151695 [Indexed for MEDLINE]

Know more about