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K Heintze

Publications and source records attributed to K Heintze.

34 records · Page 2Linked to original sources

Effects of hydrostatic pressure on fluid transfer by the isolated gallbladder.

The influence of hydrostatic pressure elevation on fluid absorption by the isolated guinea pig gallbladder was determined following addition of various smooth muscle spasmogens to the serosal bathing medium. Acetylcholine, prostaglandin E1 and ouabain increased intraluminal pressure from about 4 cm H2O to 13 cm H2O. The pressure increase was associated with a marked but transient stimulation in fluid transfer. The same phenomenon was observed following an increase in hydrostatic pressure by addition of Ringer's solution to the gallbladder lumen. Evidence is presented to support the hypothesis that this phenomenon represents the extrusion of an edema from the gallbladder wall. Two observations favour this explanation: 1. The wet weights of gallbladder subjected to high intraluminal hydrostatic pressure were only one third of those at low pressure. 2. Microscopic examination of the wall of gallbladders at low pressure showed a marked submucosal edema.

Acetylcholine↗

Triphasic effect of prostaglandins E1, E2 and F2alpha on the fluid transport of isolated gall-bladder of guinea-pigs.

Prostaglandins (PGs) F2alpha, E1 and E2 exerted a triphasic influence on the fluid transport of isolated guinea-pig gall-bladders, when applied to the serosal side. PGE1 and PGE2 produced these effects in lower concentrations than F2alpha. Directly after PG addition to the serosal side a short stimulation of fluid transport to between 200 and 400% was observed. The stimulatory effect of PGs was most distinct in gall-bladders from female guinea-pigs, less pronounced in male and nearly absent in pregnant animals. Since PGs increased intraluminal hydrostatic pressure in gall-bladders by contraction of the smooth muscle, experiments were performed in which hydrostatic pressure was increased by different procedures. These included the addition of imidazole (10- minus 2 M), raising of K+ in the bathing solution and an increase in intraluminal pressure by addition of Ringer's solution into the lumen. All three procedures stimulated fluid reabsorption temporarily in the same way as PGs, hence increase of intraluminal pressure is thought to be the reason for the observed temporary stimulation of fluid transport. Direct evidence for this thesis was obtained when the gall-bladder was mounted as a flat sheet over a chamber; in this preparation no stimulation of fluid transport was obtained. The second phase of the PG influence was characterized by a concentration-related inhibition of fluid reabsorption followed by a significant but small reverse of fluid transport (secretion of fluid). When PGs were applied to the mucosal side, only an inhibition of fluid transport was observed, which was much weaker compared to the addition to the serosal side.

Animals↗

[The effect of the plasma substitutes hydroxyethyl starch and dextrane-60 on the kidney function of dogs in acute haemorrhagic shock (author's transl)].

In 14 dogs during experimentally induced haemorrhagic shock the effects of 6% solutions of hydroxyethyl starch and Dextran-60 were compared. As main parameters of the renal function the arterial and venous pressures, renal blood flow, creatinine-clearance as measure of the glomerular filtration rate, urinary flow rate and urinary excretion of sodium and potassium were estimated. After complete substitution of the lost blood volume both plasma substitutes increased the renal blood flow by 50%. Glomerular filtration rate returned to control values, urinary volume and potassium output increased whereas sodium output decreased slightly. If only 50% of the lost volume was substituted, the renal blood flow and filtration rate remained at or below control values. Hydroxyethyl starch and Dextran-60 proved to be almost equally effective in restoring renal function.

Animals↗