Effect of endothelin-3 (ET-3) on renal function in rat perfused kidney.
We examined the effect of endothelin-3 (ET-3) at a high dose (pressor dose) and a low dose (non-pressor dose) in rat perfused kidney (PK), since ET-3 has recently been reported to exert a vasodilator action especially at a low dose. Kidneys were perfused with Krebs-Henseleit buffer at a fixed flow rate (6 ml/min) in situ. After collection of the renal venous effluent and urine for 20 min, vehicle (saline; n = 6), 10(-13)M ET-3 (low dose; n = 6) or 10(-8) M ET-3 (high dose; n = 6) was added to the perfusate, and sample collection was performed for the same period with each. The high dose of ET-3 significantly increased the perfusion pressure, fractional sodium excretion and synthesis of prostaglandins (PGs) consistently with a significant reduction in the glomerular filtration rate (GFR). On the other hand, the low dose of ET-3 significantly increased the GFR, urine volume and free-water clearance with no change in the perfusion pressure or synthesis of PGs. These findings suggest that a low dose of ET-3 can increase the glomerular capillary ultrafiltration coefficient and that ET-3 exerts an influence on sodium and water handing in the rat PK.
Watanabe
M
M
Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan.
Izumi
Y
Y
Soma
M
M
Watanabe
Y
Y
Fukuda
N
N
Abe
Y
Y
Ito
M
M
Kageura
H
H
Nakayama
T
T
Hatano
M
M
D000818:Animals; D015232:Dinoprostone / Q000097:blood; D004305:Dose-Response Relationship, Drug; D016232:Endothelins / Q000494:pharmacology*; D005919:Glomerular Filtration Rate / Q000187:drug effects; D007668:Kidney / Q000187:drug effects*; D008297:Male; D010477:Perfusion; D011460:Prostaglandins F / Q000097:blood; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000652:urine; D013929:Thromboxane B2 / Q000097:blood; D014556:Urine; D014867:Water / Q000378:metabolism
D016232:Endothelins; D011460:Prostaglandins F; D014867:Water; D013929:Thromboxane B2; D012964:Sodium; D015232:Dinoprostone; C100006:prostaglandin F1