Nonimmunological alterations of glomerular filtration by s-PAF in the rat kidney.
Rat kidneys were isolated and perfused with a cell-free perfusion buffer containing 4% albumin. Infusion of platelet activating factor (s-PAF) into the isolated perfused kidney caused a dose-dependent fall in renal vascular resistance (RVR): 12 +/- 6% at 10 nM s-PAF, 18 +/- 3% at 100 nM s-PAF and 20 +/- 7% at 1 microM s-PAF. Glomerular filtration rate fell by 32 +/- 5% at 10 nM, 38 +/- 6% at 100 nM, and 52 +/- 10% at 1 microM. s-PAF (50 nM) increased urinary protein excretion after 20 minutes. Because GFR fell to a greater extent than RVR, possible changes in glomerular permeability after s-PAF treatment were assessed morphologically using native ferritin. After s-PAF treatment (100 nM), the number of ferritin particles/micron2 increased from 1.2 +/- 0.9 (control) to 795 +/- 69 in the glomerular basement membrane (GBM) and from 0.2 +/- 0.06 (control) to 98 +/- 29 in lamina rara externa (LRE). To quantitate changes in fixed anionic charges, polyethylenimine (PEI) was quantitated morphologically in GBM. No significant change between s-PAF treated and untreated kidneys was seen. s-PAF did not alter the sialoglycoprotein pattern in the perfused kidney as assessed by lysozyme staining. These results are in contrast to findings with s-PAF in vivo where in addition to increased glomerular permeability, a reduction of fixed anionic charges is seen.(ABSTRACT TRUNCATED AT 250 WORDS)
Schwertschlag
U S
US
Department of Medicine, Duke University Medical Center, Durham, North Carolina.
Dennis
V W
VW
Tucker
J A
JA
Camussi
G
G
D000818:Animals; D002199:Capillary Permeability; D005293:Ferritins; D005919:Glomerular Filtration Rate; D007668:Kidney / Q000502:physiology*; D008297:Male; D010477:Perfusion; D010972:Platelet Activating Factor / Q000494:pharmacology*; D011507:Proteinuria / Q000209:etiology; D051381:Rats; D011919:Rats, Inbred Strains; D014655:Vascular Resistance
D010972:Platelet Activating Factor; D005293:Ferritins