摘要:

The uptake of radioactively labelled glibenclamide was studied in microdissected pancreatic islets of obese-hyperglycemic mice. The steady-state concentration reached was linearly related to the medium concentration of glibenclamide. This is in contrast to the short-term uptake, for which there was evidence for saturation. The amounts of glibenclamide incorporated increased by more than 100 % when the plasma membranes were made permeable to sucrose by reducing the osmolality of the incubation medium. No binding of glibenclamide in excess of sucrose could be detected after increasing the albumin concentration to 10 mg/ml. The steady-state concentrations reached were approximately the same in the presence of different monovalent cations. The observation of a reduced uptake of glibenclamide in the presence of cysteine raises the question whether sulfonylureas stimulate insulin release by reacting with sulf-hydryl groups in the /3-cell membrane.

ISSN:0031-7012    

DOI:10.1159/000136498

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

In rabbits pretreated with i.p. probenecid, the hyperthermia induced by 5-hydroxytryptophan (5-HTP) was markedly potentiated. There was, however, no change in the level of 5-hydroxytryptamine (5-HT) in the hypothalamus and brain stem. Consequently, there is no direct relation in this situation between hyperthermia and the cerebral levels of 5-HT. High doses of Ro4-4602 inhibited the hyperthermic effect of 5-HTP and of 5-HTP in the presence of probenecid, although the levels of 5-HT in the hypothalamus and brain stem were elevated. At the same time, a decrease in the concentration of 5-hydroxyindolacetic acid (5-HIAA) was observed in the cerebrospinal fluid (CSF). The authors suggest from their findings that Ro4-4602 may inhibit the abnormal synthesis of 5-HT induced by an excess of 5-HTP in hypothalamic thermoregulatory structures other than 5-hydroxytryptaminergic structures.

ISSN:0031-7012    

DOI:10.1159/000136499

出版商:S. Karger AG    

年代:1974

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000135493

出版商:S. Karger AG    

年代:1964

数据来源: Karger

摘要:

The effect of prostaglandin E2 (PGE2) on urine excretion was investigated in chloralose anesthetized cats, rabbits, and isolated Krebs’ perfused rabbit kidney. In contrast to the vascular effect, single i.v. injection of PGE2 induced a higher increase in urine volume than that produced by single injection of the compound into the aorta. In isolated kidney, perfused with Krebs’ solution, injection of PGE2 into the renal artery produced a slight increase in urine volume. But when the same dose of PGE2 was injected through the pulmonary artery of blood-free isolated perfused guinea-pig lung, and the venous return was perfused through the kidney, a highly significant enhancement in urine volume was obtained. These results suggest that the pulmonary circulation may have an important role on the mechanism of diuresis induced by i.v. injection of PGE2. The possible mechanism of this effect is discus

ISSN:0031-7012    

DOI:10.1159/000136500

出版商:S. Karger AG    

年代:1974

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000135494

出版商:S. Karger AG    

年代:1964

数据来源: Karger

摘要:

Quingestanol acetate was absorbed rapidly and showed a high order of bioavailability after oral administration to women. The composition of the radioactive steroids in the plasma of the subjects suggests that the initial biotransformation of the drug involves two pathways, namely, deacylation to quingestanol and O-dealkylation to norethindrone acetate, and that both of these metabolites are subsequently converted to norethindrone.

ISSN:0031-7012    

DOI:10.1159/000136501

出版商:S. Karger AG    

年代:1974

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000135495

出版商:S. Karger AG    

年代:1964

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000135496

出版商:S. Karger AG    

年代:1964

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000135497

出版商:S. Karger AG    

年代:1964

数据来源: Karger

摘要:

Eight adult chimpanzees with prior histories of long-term exposure to marihuana were mated either with each other or with drug-naive chimpanzees from the Holloman chimpanzee colony. No alterations of sexual activity were observed in the drug-experienced animals. The incidence of normal births where one or both parents had extensive prior marihuana experience was the same as that for non-drug colony chimpanzees.

ISSN:0031-7012    

DOI:10.1159/000136502

出版商:S. Karger AG    

年代:1974

数据来源: Karger