Aging and endothelin-1 induced vascular contractions.
Contractions produced by endothelin-1 (0.3-30 nM) have been investigated in aorta, renal arteries and mesenteric arteries from 2- and 24-month-old Sprague-Dawley rats. In senescent rats the EC50 values of endothelin-1 for aorta and renal artery were significantly increased (aorta: from 6.2 to 12 nM; renal artery: from 5.2 to 7.8 nM). For mesenteric artery the EC50 value (4.3 nM) was unchanged by aging, whereas the maximal contractile response to endothelin-1 was enhanced (from 8.3 to 11.7 mN). In contrast, there was no significant age-related difference in the maximal endothelin-1 response of aorta and renal artery. The present data demonstrate a reduced sensitivity for aorta and renal artery and an enhanced maximal response to endothelin-1 in the mesenteric artery in senescent rats.
Weinheimer
G
G
Dept. of Pharmacology, Goedecke Research Institute, Freiburg, Federal Republic of Germany.
Dooley
D J
DJ
Cazzonelli
M
M
Osswald
H
H
D000375:Aging / Q000502:physiology*; D000818:Animals; D001011:Aorta / Q000502:physiology; D016232:Endothelins / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D008638:Mesenteric Arteries / Q000502:physiology; D009119:Muscle Contraction; D009131:Muscle, Smooth, Vascular / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012077:Renal Artery / Q000502:physiology
D016232:Endothelins