Effects of phospholipids on renal function.
The effects of two classes of phospholipids (PL) on renal function have been studied. Bolus injections of 1 ng (10 pmol) of lysophosphatidylcholine (LPC) caused natriuresis and diuresis in rats. Natriuretic activity was eliminated by substituting unsaturated bonds in the 1-acyl group and by removing the choline group on the sn-3 position. Natriuretic activity was not affected by substitution of 1-alkyl for 1-acyl groups. In the dog, LPC was natriuretic when given as a bolus of 3.0 micrograms/kg or as a constant infusion at 5 ng/kg/min. To explore further the effect of alkyl PLs on renal function, a series of studies with platelet activating factor (PAF) was performed. PAF injected directly into the renal artery (IR) in bolus doses of 0.5-10 ng/kg caused renal vasodilation that was blocked by a specific PAF receptor antagonist. This effect was not due to release of vasodilatory eicosanoids, dopamine, or nitric oxide (NO). PAF given IR as a continuous infusion at 2.5 ng/kg/min attenuated the renal vasoconstrictor effects of angiotensin II and norepinephrine but not vasopressin. This effect to attenuate vasoconstriction was blocked by the NO inhibitor N-monomethyl-L-arginine. These studies using picomolar amounts of PL suggest a physiologic role for these compounds in control of renal function.
Buckalew
V M
VM
Department of Medicine, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27157-1053.
Strandhoy
J W
JW
Handa
R K
RK
D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D004231:Diuresis / Q000187:drug effects*; D004285:Dogs; D006439:Hemodynamics / Q000187:drug effects*; D007668:Kidney / Q000187:drug effects* / Q000502:physiology; D008244:Lysophosphatidylcholines / Q000008:administration & dosage / Q000494:pharmacology*; D019331:NG-Nitroarginine Methyl Ester; D009318:Natriuresis / Q000187:drug effects*; D009569:Nitric Oxide / Q000037:antagonists & inhibitors; D009638:Norepinephrine / Q000494:pharmacology; D010972:Platelet Activating Factor / Q000494:pharmacology*; D051381:Rats; D012077:Renal Artery / Q000187:drug effects; D012079:Renal Circulation / Q000187:drug effects; D013329:Structure-Activity Relationship; D014664:Vasodilation / Q000187:drug effects; D014667:Vasopressins / Q000494:pharmacology
D008244:Lysophosphatidylcholines; D010972:Platelet Activating Factor; D014667:Vasopressins; D000804:Angiotensin II; D009569:Nitric Oxide; D001120:Arginine; D019331:NG-Nitroarginine Methyl Ester; D009638:Norepinephrine