Dencker H

Intestinal absorption, demethylation, and enterohepatic circulation of imipramine.

The intestinal absorption and metabolism of single oral doses of imipramine (ip) have been studied in man by portal catheterization. The concentration of ip and the formed desipramine (dmi) was followed in blood‐plasma obtained from the portal and cubital veins. The absorption of ip seemed to be completed 80 min after the administration of the drug. There was no sign of demethylation of ip during the passage across the intestinal wall. Evidence was found of an enterohepatic circulation of both ip and dmi.

Dilator for treatment of strictures in the upper part of the rectum and the sigmoid

SummaryAn instrument for dilating strictures in the upper part of the rectum and sigmoid colon is described. With this instrument the intestine can be dilated to practically normal width. The risk of injury to the intestinal wall appears very small.

Intestinal transport of carbohydrates as measured by portal catheterization in man.

A method for studying the transport of an intraduodenally instilled solution of carbohydrates by simultaneous sampling of portal and arterial blood is described. The transport of glucose, maltose and fructose was measured in ambulant adult patients with cancer of the colon without liver metastases. They were in a normal nutritional state. 200 ml of a 6-percent carbohydrate solution was instilled intraduodenally within 10 min. Portal glucose rise was not slower after instillation of maltose than after that of glucose. Transport of fructose was completed somewhat later than that of glucose. The difference in the portal-arterial blood sugar concentration was used as a measure of the actual net influx of carbohydrates into the portal circulation at certain intervals. After instillation of glucose or maltose the portal-arterial glucose difference showed two maxima. The interposed minimum often reached a slightly negative value. It is tentatively assumed that this unexpected finding was due to accumulation of glucose in the intestinal mucosa, followed by a release of the accumulated glucose coinciding with the subsequent fall of arterial blood glucose concentration. Absorbed fructose was not found to behave in the same manner. Although some transformation of fructose to glucose during transport through the intestinal wall may have occurred, it was less than could be detected in these experiments.

Human intestinal absorption of glucose measured by portal catheterization.

A method for studying intestinal absorption with the aid of a catheter in the portal vein is described. The absorption of glucose from the human small intestine was estimated by simultaneous sampling of portal and arterial blood. A dose of 12 g glucose deposited intraduodenally was absorbed within approximately 1 hour, the major part of it within 30 minutes.

Mass fragmentographic determination of conjugated neutral 17-ketosteroids in peripheral and portal venous blood: Effect of ampicillin administration

Abstract Dehydroepiandrosterone, androsterone and epiandrosterone sulphate and androsterone glucuronide were determined by mass fragmentography in pools of peripheral and portal venous plasma from postmenopausal women. Samples were analyzed both before and after oral administration of ampicillin for 4 days (2 g per day). The peripheral ketosteroid monosulphate concentrations were within the normal range for postmenopausal women reported in the literature. Androsterone glucuronide was present in concentrations of 42 μ/1 plasma. The peripheral and portal venous metabolite levels did not differ from each other either before or after ampicillin administration. With the exception of decreasing dehydroepiandrosterone sulphate levels ampicillin did not affect either portal or peripheral metabolite concentrations. The higher pre-ampicillin dehydroepiandrosterone sulphate concentrations may reflect a stress situation as the mean cortisol levels were also higher, but not significantly so in these samples.