Influence of Prostaglandins A_1, E₁, E₂, and F_2α on Renal Blood Flow and Plasma Renin Activity

Abstract

The effects of different prostaglandins (PG) on serial determinations of renal blood flow (RBF), mean arterial blood pressure (MABP), renal vascular resistance (RVR) and renin release were investigated in the conscious, chronically instrumented dog. 2 months after right-sided nephrectomy, female beagle dogs (n=6) were implanted with an electromagnetic flow probe and an inflatable pneumatic cuff around the left renal artery, and a catheter was inserted into the aorta above the renal artery. In repeated experiments, different prostaglandins (PGA_1, E₁, E₂ and F_2α) were infused above the renal artery at increasing doses (infusion time 15 min, doses 0.03–1.0µg min^-1 kg^-1). Lower and medium doses induced an increase of RBF, which returned to or were slightly below control levels with higher doses. PGA, appeared to be the most potent vasodilator with a significant hypotensive activity and the greatest augmentation of RBF. Simultaneously, renin release was most pronounced by PGA,.

Pharmacokinetics of Insect Repellent N,N-Diethyl-m-toluamide in Beagle Dogs following Intravenous and Topical Routes of Administration

“…With MRT of 2.34 ( 0.12 h and t 1/2 of 2.56 ( 0.29 h, the elimination of DEET appeared to be fast. The mean CL was 2.66 ( 0.17 L/h/kg, approximately 2-fold higher than the renal blood flow which was estimated as 1.38 L/h/kg, 23 suggesting that DEET was partially cleared intrahepatically, as in humans. 7 The V ss value (6.21 ( 0.32 L/kg) was approximately 9-fold higher than the total body water of a lean dog (0.7 L/kg), 24 indicating that DEET underwent extensive extravascular distribution.…”

Prostaglandin E₂ Promotes Hypotension on Low-Sodium Hemodialysis

“…As far as the vasodilating prostacyclin is concerned, an increase in plasma levels has been found during the initial phase of dialysis parallel to the forma tion of platelet microaggregates [33]. In addition, increas ing plasma levels of thromboxane have been observed in the course of hemodialysis [34], The vasodilating action of exogenous PGE has been extensively demonstrated in animals [35] and man [36]. This is not necessarily followed by a reduction in arterial pressure in the presence of intact antagonistic systems [37], Likewise, volume deple tion in dialysis patients who present with a near to normal blood volume [38] in connection with hemorrhage [39] or hemofiltration [11-13] does not necessarily cause hypo tension due to counterregulation.…”