Effect of Renal Venous Occlusion on Intrarenal Pressure.

Abstract

The individud variations of blood sugar (solid kin-) and serum inorganic phosphorus (dotted lines) from the initial values during the diffea-ent perids of the experiment.tion of glucose alone( 18) that occurs under the influence of ACTH is not due to a deficiency in insulin production. It was passible to observe that the changes of blood sugar tended to appear and disappear sooner than its mechanism although closely related phenomena. It may be that these experiments could be interpreted as an in vivo reduction of the rate of phosphorylization induced by adreno-cortical stimulation.

Vascular Adjustments to Increased Transmural Pressure in Cat and Man with Special Reference to Shifts in Capillary Fluid Transfer

“…In these experiments, a n external pressure on the foot was created by the water in the plethysmograph and also perhaps to some extent by the latex stocking. T o keep the veins patent, the intravascular pressure must exceed this external pressure (compare the socalled "water-fall phenomenon") (Permutt, Bromberger-Barnea and Bane 1962) described in kidneys (Swann, Montgomery and Lowry 1951) and in plethysmographic preparations (Kjellmer 1963). The rise in venous pressure to about 85 mm Hg on standing will, due to this high resting venous pressure, imply an effective pressure increase of only 50 to 55 mm Hg.…”

Extravasation of Blood and Blood Toxicity Drives Tubular Injury from RBC Trapping in Ischemic AKI

“…Venous clamping, blockage, or physiological blockage of the vessels that drain the medulla following renal arterial ischemia, results in an increase in intravascular pressure within the kidney. 70 , 71 To examine the role of renal perfusion pressure on RBC trapping and injury, we compared blood-perfused kidneys with venous clamping at normal and low renal perfusion pressures. As RBC trapping and tubular injury were similar at both normal and low renal perfusion pressures, this suggests that RBC trapping and tubular blood toxicity may occur even at low arterial pressures, such as in shock.…”

An Indirect Method for Estimating Tissue Pressure with Special Reference to Tissue Pressure in Muscle during Exercise1

“…Tissue pressure acts directly on the venules and veins. The intravascular pressure in venules and veins can never be lower than tissue pressure if blood flow is to be preserved as has been shown experimentally for different tissues such as the skin of the forearm, the kidney, the lung and the eye (Ryder et al 1944, Swann et al 1951, Permutt, Bromberger-Barnea and Bane 1962and Bill 1962.…”

“…Judging from the literature, tissue pressure is usually measured via a thin needle inserted in the tissue and measuring either the equilibrium pressure of a small quantity of fluid injected into the tissue (e. g. Swann, Montgomery and Lowry 1951) or the minimum pressure necessary to force a small amount of fluid into the tissue (e. g. Wells, Youmans and Miller 1938). This group of methods, however, has been criticized even by those who used them (McMaster 1946 and others).…”