TY  - JOUR
AU  - van Drongelen, J
AU  - van Koppen, A
AU  - Pertijs, J
AU  - Gooi, JH
AU  - Parry, LJ
AU  - Sweep, FCGJ
AU  - Lotgering, FK
AU  - Smits, P
AU  - Spaanderman, MEA
Y2  - 2014/05/22
Y1  - 2012/03/01
SN  - 8750-7587
UR  - http://hdl.handle.net/11343/33040
AB  - Relaxin mediates renal and mesenteric vascular adaptations to pregnancy by increasing endothelium-dependent vasodilation and compliance and decreasing myogenic reactivity. Diet-induced overweight and obesity are associated with impaired endothelial dysfunction and vascular remodeling leading to a reduction in arterial diameter. In this study, we tested the hypothesis that local vascular responses to relaxin are impaired in diet-induced overweight female rats on a high-fat cafeteria-style diet for 9 wk. Rats were chronically infused with either relaxin or placebo for 5 days, and vascular responses were measured in isolated mesenteric arteries and the perfused kidney. Diet-induced overweight significantly increased sensitivity to phenylephrine (by 17%) and vessel wall thickness, and reduced renal perfusion flow (RPFF; by 16%), but did not affect flow-mediated vasodilation, myogenic reactivity, and vascular compliance. In the normal weight rats, relaxin treatment significantly enhanced flow-mediated vasodilation (2.67-fold), decreased myogenic reactivity, and reduced sensitivity to phenylephrine (by 28%), but had no effect on compliance or RPFF. NO blockade by l-NAME diminished most relaxin-mediated effects. In diet-induced overweight rats, the vasodilator effects of relaxin were markedly reduced for flow-mediated vasodilation, sensitivity to phenylephrine, and myogenic response compared with the normal diet rats, mostly persistent under l-NAME. Our data demonstrate that some of the vasodilator responses to in vivo relaxin administration are impaired in isolated mesenteric arteries and the perfused kidney in diet-induced overweight female rats. This does not result from a decrease in Rxfp1 (relaxin family peptide receptor) expression but is likely to result from downstream disruption to endothelial-dependent mechanisms in diet-induced overweight animals.
LA  - English
PB  - AMER PHYSIOLOGICAL SOC
KW  - Reproduction; Systems Physiology; Expanding Knowledge in the Medical and Health Sciences; Reproductive System and Disorders
T1  - Impaired vascular responses to relaxin in diet-induced overweight female rats
DO  - 10.1152/japplphysiol.00470.2011
IS  - Journal of Applied Physiology
VL  - 112
IS  - 6
SP  - 962-969
L1  - /bitstream/handle/11343/33040/297656_17071.pdf?sequence=1&isAllowed=n
ER  -