Comparison of the effects of hypercholesterolaemia on relaxation responses in aortas of spontaneously hypertensive rats and Dahl salt-sensitive rats.
1. We investigated the effects of hypercholesterolaemia on relaxation responses in thoracic aortas isolated from two different types of hypertensive rats; spontaneously hypertensive rats (SHR) and Dahl salt-sensitive rats (DSR). 2. All rats fed the high cholesterol diet for 8 weeks showed a significant increase in the serum cholesterol level. The high cholesterol diet did not change the blood pressure of SHR, but increased that of hypertensive DSR fed a high-salt diet. 3. In aortas of SHR, the high-cholesterol diet did not change the endothelium-dependent and -independent relaxation induced by acetylcholine (ACh) and sodium nitroprusside (SNP), respectively. 4. In aortas of hypertensive DSR, the high-cholesterol diet notably reduced the ACh-induced relaxations and slightly reduced SNP-induced relaxation. 5. These results suggest that hypercholesterolaemia causes greater impairment of endothelium-dependent relaxation in rat aorta with salt-induced hypertension than genetic hypertension.
Kitagawa
S
S
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Mukogawa Women's University, Koshein Kyuban-cho, Nishinomiya, Japan.
Sameshima
E
E
Yamaguchi
Y
Y
Kwon
Y
Y
Shinozuka
K
K
Kunitomo
M
M
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002784:Cholesterol / Q000097:blood; D002791:Cholesterol, Dietary / Q000494:pharmacology; D004032:Diet; D006937:Hypercholesterolemia / Q000097:blood / Q000503:physiopathology*; D006973:Hypertension / Q000139:chemically induced / Q000235:genetics / Q000503:physiopathology*; D007476:Ionophores / Q000494:pharmacology; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects / Q000502:physiology; D009131:Muscle, Smooth, Vascular / Q000503:physiopathology*; D009599:Nitroprusside / Q000494:pharmacology; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY
D000959:Antihypertensive Agents; D002791:Cholesterol, Dietary; D007476:Ionophores; D009599:Nitroprusside; D000001:Calcimycin; D002784:Cholesterol; D000109:Acetylcholine