Cardio-renal effects of endothelin-3 in the rat.
Endothelin-3 (ET-3), a recently described vasoconstricting peptide was infused in Inactin anesthetized rats at 0, 40, 170 or 340 ng/kg/min for 45 minutes (n = 8 in each group). ET-3 infusion increased mean arterial pressure at all infusion rates by increasing total peripheral resistance. Cardiac output (delta CO) was significantly decreased at the two highest ET-3 infusion doses. The decrease in cardiac output was associated with a decrease in central venous pressure and stroke volume and an increase in hematocrit. ET-3 infusion at 40 ng/kg/min increased sodium excretion (delta UNaV) by 0.14 +/- 0.08 microEq/min (p less than 0.05 compared to vehicle infusion) without affecting the glomerular filtration rate (GFR). At higher infusion rates ET-3 markedly decreased the GFR, urine flow and urinary potassium excretion. ET-3 infusion significantly increased circulating levels of ANF. The present study demonstrates that ET-3 increases blood pressure by increasing total peripheral resistance but decreases cardiac output. Further, ET-3 has natriuretic effects at low doses but markedly attenuates renal function at high doses.
Zimmerman
R S
RS
Ochsner Clinic, New Orleans, LA 70121.
Martinez
A J
AJ
MacPhee
A A
AA
Barbee
R W
RW
D000818:Animals; D009320:Atrial Natriuretic Factor / Q000097:blood; D001794:Blood Pressure; D002302:Cardiac Output; D002320:Cardiovascular Physiological Phenomena; D002496:Central Venous Pressure; D004231:Diuresis; D016232:Endothelins / Q000008:administration & dosage / Q000494:pharmacology*; D005919:Glomerular Filtration Rate; D006400:Hematocrit; D007668:Kidney / Q000502:physiology*; D008297:Male; D009318:Natriuresis; D011188:Potassium / Q000652:urine; D051381:Rats; D011919:Rats, Inbred Strains; D013318:Stroke Volume; D014655:Vascular Resistance
D016232:Endothelins; D009320:Atrial Natriuretic Factor; D011188:Potassium