Chronic intracerebroventricular infusions of endothelin elevate arterial pressure in rats.
We investigated the effects of intracerebroventricular infusions of endothelin on cardiovascular and endocrinological responses using conscious, unrestrained rats. Chronic intracerebroventricular infusions of endothelin, 10 pmol/h for 7 days, elevated arterial pressure significantly on days 5, 6 and 7 of the infusion, compared with intracerebroventricular infusions of the vehicle. Heart rate decreased from day 1 of the infusion of endothelin until the end of the experiment. The urinary excretion of norepinephrine increased on day 3 and epinephrine increased on days 3, 4 and 5 of endothelin infusion. The urinary excretion of arginine vasopressin increased on day 5, 6 and 7 of the infusion. These findings suggest that chronic intracerebroventricular infusions of endothelin elicit elevations in arterial pressure and that the initiation of blood pressure rises can be related to sympathetic activation although the actual role for the pressor responses has been played by the released arginine vasopressin.
Nishimura
M
M
Department of Clinical Laboratory and Medicine, Kyoto Prefectural University of Medicine, Japan.
Takahashi
H
H
Matsusawa
M
M
Ikegaki
I
I
Sakamoto
M
M
Nakanishi
T
T
Hirabayashi
M
M
Yoshimura
M
M
D000818:Animals; D001127:Arginine Vasopressin / Q000652:urine; D001794:Blood Pressure / Q000187:drug effects*; D001921:Brain / Q000187:drug effects*; D016232:Endothelins / Q000008:administration & dosage / Q000494:pharmacology*; D004837:Epinephrine / Q000652:urine; D006339:Heart Rate / Q000187:drug effects; D007262:Infusions, Intravenous; D007276:Injections, Intraventricular; D008297:Male; D009638:Norepinephrine / Q000652:urine; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000187:drug effects*; D017466:Receptors, Endothelin; D013564:Sympathetic Nervous System / Q000187:drug effects* / Q000502:physiology
D016232:Endothelins; D011956:Receptors, Cell Surface; D017466:Receptors, Endothelin; D001127:Arginine Vasopressin; D009638:Norepinephrine; D004837:Epinephrine