Effects of psychosocial stress on endothelium-mediated dilation of atherosclerotic arteries in cynomolgus monkeys.
The objectives of this study were to determine if psychosocial stress impairs dilation through endothelium-derived relaxing factor (EDRF)-mediated mechanisms and if this effect is long lasting. Monkeys were fed an atherogenic diet for 36 mo while in one of three experimental conditions: (a) stable social groups ("unstressed," n = 6); (b) unstable social groups for the first half of the experiment and stable groups for the second half ("early stress," n = 8); and (c) stable groups for the first half of the experiment and unstable groups for the second half ("late stress," n = 6). Iliac arteries were studied in organ chambers containing Krebs' buffer and 10(-6) M indomethacin. Arteries from the late stress group had impaired dilation (shift of the dose-response curve down and to the right) to acetylcholine and the calcium ionophore A23187 (for both, P < 0.05), but not to nitroprusside (P > 0.05), compared with unstressed or early stress monkeys. NG-methyl-L-arginine reduced the dose-response curve to both acetylcholine and A23187 in the unstressed group and resulted in similar vascular responses among all three groups (P > 0.05). We conclude that current, but not previous, exposure to chronic stress impairs endothelium-mediated dilation of atherosclerotic iliac arteries of cynomolgus monkeys through an EDRF-mediated mechanism.
Williams
J K
JK
Department of Comparative Medicine, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, North Carolina 27157.
Kaplan
J R
JR
Manuck
S B
SB
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D001161:Arteriosclerosis / Q000503:physiopathology* / Q000523:psychology*; D000001:Calcimycin / Q000494:pharmacology; D004036:Diet, Atherogenic; D004305:Dose-Response Relationship, Drug; D007083:Iliac Artery / Q000187:drug effects / Q000503:physiopathology*; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D008252:Macaca fascicularis; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000503:physiopathology*; D009599:Nitroprusside / Q000494:pharmacology; D012919:Social Behavior; D013315:Stress, Psychological / Q000503:physiopathology*; D014664:Vasodilation / Q000187:drug effects; D019323:omega-N-Methylarginine
D009599:Nitroprusside; D019323:omega-N-Methylarginine; D000001:Calcimycin; D001120:Arginine; D000109:Acetylcholine; D007213:Indomethacin