The effect of angiotensin, noradrenaline and vasopressin on blood flow distribution in the rat kidney

Abstract

SUMMARY1. The effect of val5-angiotensin II amide, noradrenaline and vasopressin, on kidney volume and intrarenal distribution of carbon particles and thioflavine S was examined in the rat.2. Angiotensin produced a dose-dependent shrinkage of the kidney coinciding with the rise in systemic blood pressure. Noradrenaline and vasopressin, however, produced reduction in kidney volume only in much higher doses than were necessary to produce a pressor effect.3. An intravenous infusion of angiotensin sufficient to produce a diuretic response resulted in a striking increase in glomerular content of injected carbon particles, and a marked reduction in filling of the capillary plexuses of the subcortex and outer medulla. The reduction in outer medullary filling was also observed using the thioflavine S technique.4. Noradrenaline infused in amounts sufficient to produce diuresis, aortic constriction above the kidney and vasopressin injection produced no measurable change in carbon particle distribution.5. The reduction in capillary blood flow produced by angiotensin may result in impaired tubular reabsorptive capacity by reducing peritubular removal of reabsorbate, or by reducing oxygen availability. Thus the vasoconstrictor effects of angiotensin may explain its diuretic action.

Perfusion CT Assessment of Tissue Hemodynamics Following Hepatic Arterial Infusion of Increasing Doses of Angiotensin II in a Rabbit Liver Tumor Model

“…These results are similar to the fi ndings reported by Burke et al ( 6 ) where heterogeneous distribution of a tissue-trapping BF tracer was seen on PET images after angiotensin II was infused into the hepatic arteries of patients with colorectal liver metastases. The observed spatial heterogeneity is consistent with the vasoconstrictor exerting its effects primarily on smaller distal arterial branches, as has been shown in the kidney (27)(28)(29). This explanation is supported by the results reported by Ekelund and Lunderquist ( 1 ) showing that after hepatic pharmacoangiography performed with angiotensin II, a marked slowing of BF through the peripheral hepatic arterial branches was generally seen, to the extent that some small vessels were still fi lled with contrast material 10-12 seconds after the injection, which occurred 10-20 seconds after the delivery of angiotensin II.…”

Effect of Exogenous Angiotensin-II on Local Blood Flow in Kidneys with Neoplasm: Experiments in the rat

“…In general, the present effects of Ang-I1 on BP and LRBF correspond well with previous results obtained in the rat by other methods (FINBERG & PEART 1972, RENTSCH et coll. 1976, ARENDSHORST & FINN 1977 as well as in the dog by the present technique (AUKLAND).…”

The effect of vasopressin on renal blood flow and its distribution in the rat.

“…Fourman & Kennedy, 1966;Aukland, 1968;Fisher, Griinfeld & Barger, 1970;Finberg & Peart, 1972; Banks, 1976;Akatsuka, Moran, Morgan & Wilson, 1977;Johnson, Park & Malvin, 1977). One probable explanation for this lack of agreement is the variety of techniques used for assessing intrarenal blood flow, some being more reliable than others.…”