Changes in endothelium-dependent relaxation and levels of cyclic nucleotides in the perfused mesenteric arterial bed from streptozotocin-induced diabetic rats.
The influence of diabetes on the function of vascular endothelium was examined with respect to the role of nitric oxide (NO) in the regulation of blood pressure (BP) in vivo, the vascular relaxation, and levels of cAMP and cGMP in the effluent of the perfused mesenteric arterial bed from streptozotocin-induced diabetic rats. An intravenous injection of 100 mg/kg N omega-nitro-L-arginine methylester (L-NAME) caused hypertension in both diabetic rats and controls. However, the degree of hypertension in the diabetic rats was significantly lower than that in the controls. Acetylcholine (ACh)-induced vasorelaxation of the perfused mesenteric arterial bed decreased in diabetic rats. At the same time, the levels of cAMP and cGMP in the effluent of the diabetic rats were also lower than in the controls. These data indicate that NO formation is involved in the regulation of BP in rats, and is decreased in diabetic rats, due to an impairment of the vascular endothelium, including the endothelium of resistance vessels.
Abiru
T
T
Biology Laboratory, Yamasa Corporation, Chiba, Japan.
Watanabe
Y
Y
Kamata
K
K
Kasuya
Y
Y
D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D000242:Cyclic AMP / Q000378:metabolism*; D006152:Cyclic GMP / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism / Q000503:physiopathology*; D004730:Endothelium, Vascular / Q000503:physiopathology*; D008297:Male; D008638:Mesenteric Arteries; D019331:NG-Nitroarginine Methyl Ester; D009569:Nitric Oxide / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014664:Vasodilation
D009569:Nitric Oxide; D001120:Arginine; D000242:Cyclic AMP; D006152:Cyclic GMP; D019331:NG-Nitroarginine Methyl Ester