XXXX in @entity35 : a model for unilateral renal artery stenosis in man.

@entity11605 @entity101 @entity1808 @entity2481 @entity35
Determinants of glomerular ultrafiltration were studied by micropuncture in clamped (n = 11) and unclamped (n = 7) kidneys of two-kidney @entity101 @entity35 and compared to 15 controls. Infusion of the @entity1808 antagonist and @entity11605 lowered the blood pressure significantly. Glomerular capillary pressure ( @entity2481 ) in clamped kidneys was decreased to 56 +/- (SD) 3 vs. 61 +/- 3 mm Hg in controls. Early proximal flow rate (EPFR) was decreased to 20 +/- 1 vs. 26 +/- 2 nl/min in controls, at an unchanged single nephron filtration fraction (SNFF), indicating a reduced glomerular plasma flow (SNGPF). Preglomerular resistance (RA) was increased by 21%. In unclamped kidneys @entity2481 was increased to 65 +/- 2 mm Hg. EPFR was increased to 32 +/- 2 nl/min, indicating, at an unchanged SNFF, an increased SNGPF. RA increased by 51%, whereas postglomerular resistance declined by 25%. The ultrafiltration coefficient was reduced by 24% in unclamped kidneys. Our results indicate that in clamped kidneys an increase of RA causes a reduction of @entity2481 and hence a reduction of pressure at the baroreceptor site which may act as a trigger mechanism for renin release.
