Chronic effects of synthetic endothelin on blood pressure and sodium excretion in rats.
Continuous infusion of endothelin at a rate of 60 micrograms/kg/day into the jugular vein of rats via osmotic minipumps induced a significant increase in systolic blood pressure, but did not induce any significant changes in urine volume and urinary sodium excretion, compared to those in vehicle-infused rats. When 6 mg/kg/day of benidipine, a newly developed calcium channel blocker, was administered simultaneously with 60 micrograms/kg/day of endothelin, the systolic blood pressure of conscious rats rose on Day 1 to only 137.0 +/- 2.4 mm Hg (P less than .05) compared to the rise to 163.8 +/- 4.7 mm Hg when endothelin alone was infused. The antihypertensive effect of benidipine was sustained. The present results suggest that endothelin can act as a circulating hormone. In addition, they clearly demonstrate that the calcium channel blocker attenuates the elevation of blood pressure induced by endothelin.
Yasujima
M
M
Second Department of Internal Medicine, Tohoku University School of Medicine, Sendai, Japan.
Abe
K
K
Kanazawa
M
M
Yoshida
K
K
Sato
M
M
Takeuchi
K
K
Tsunoda
K
K
Kudo
K
K
Kohzuki
M
M
Omata
K
K
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D004095:Dihydropyridines / Q000008:administration & dosage / Q000494:pharmacology*; D016232:Endothelins / Q000008:administration & dosage / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D007262:Infusions, Intravenous; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000652:urine*; D013997:Time Factors; D014556:Urine
D004095:Dihydropyridines; D016232:Endothelins; C061004:benidipine; D012964:Sodium