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The influence of an intraarterial infusion of PGE on the amino acid metabolism of human sceletal muscle was examined in healthy volunteers using the forearm technique. A continuous increase of perfusion from 2.9±0.1 ml/100 g × min to 5.4±1.5 after 60 min could be observed. Muscular amino acid balances were not changed after 30 min but significantly after 60 min of PGE infusion. Muscular release of most of the amino acids was reduced or shifted to an uptake. The accumulated balance of the amino acids showed a significant increase from −21.9 to +33.2 nmol/ 100 g × min after 60 min. Thus the infusion of PGE led to an inhibition of muscular proteolysis and/or to a stimulation of proteosynthesis. In view of the fact that kinines are released during exercise and are partially effective via prostaglandine liberation, the protein-anabolic effect of exercise might be explained by action of prostaglandins. [ABSTRACT FROM AUTHOR]

Intracellular cation concentrations (Nai, Ki), and the influx of Rb86 and of Na22 were measured in the erythrocytes of 22 normal women with no family history of hypertension, 16 women with untreated essential hypertension, and 14 normotensive women treated with hormonal contraceptives. Values for total Rb influx, and for its components denoting sodium pump activity (ouabain-sensitive) and Na, K co-transport (ouabain-resistant, frusemide-sensitive), were significantly greater in the hypertensive and contraceptive-treated groups than in the normal group. Na, K cotransport measured by Na influx (frusemide-sensitive) was found to be significantly increased in the contraceptive-treated but not the hypertensive group. Passive sodium diffusion (frusemide-resistant Na influx) and Ki did not differ significantly between groups. Nai was lower in the hypertensive group than in the other two groups. These findings support the hypothesis that hypertension or hormonal contraception are associated with increased leakage of K ions from erythrocytes, without a corresponding increase in passive Na influx: the change in cell membrane permeability is compensated for by increases in Na, K co-transport and sodium pump activity, adjusted to allow for altered differential permeability to K and Na ions.

In 12 patients with advanced prostatic carcinoma the effect of bromocriptine-induced hypoprolactinemia on the peripheral androgen metabolism was investigated after 3H-testosterone injection under conditions that each individual served as his own control. After a 5-day significant prolactin suppression, the elimination of 3H-label 1 h after testosterone injection was about 45% and equal to pre-bromocriptine values. The recovery of dihydrotestosterone separated by silica gel T.L.C., however, was significantly augmented, resulting in a marked decrease of the testosterone/dihydrotestosterone ratio from 12.2 to 6.3. This induced 5alpha-reductase activity after prolactin suppression is in accordance with our earlier findings on prostatic carcinoma tissue, matches well with observations of Magrini et al. on induced hyperprolactinemia and may be a new approach to the understanding of androgen dependent disorders.

An ivestigation has been performed in 49 women about the influence exerted on the glucose-tolerance, insulin and proinsulin secretion by hormonal contraceptives of different types and compositions. A disturbed dynamics of the insulin secretion with elevated values in the OGTT at two and three hours has been proven at a nearly equal degree using combined preparations (Anacyclin, Eugynon, Neogynon, Mikrogynon) or sequential preparations (Kombiquens, Ovanon). Though there has been interference with the glucose tolerance, the serum proinsulin in the OGTT showed increased levels too. When a combined preparation was applied, the proinsulin values were significantyl higher compared to a sequential type contraceptive. The observed disturbance of the insulin and proinsulin secretion is explained by a decreased sensitivity to insulin in the peripheral fat tissue. The actual dose of the estrogen-gestagen components has no influence on the described changes. Elevated insulin levels are demonstrable already during the first treatment cycle. The degree of the disturbance is independent of the duration of the medicamentous application during the first 6 contraceptive months. After withdrawal of the respective contraceptive steroid the insulin secretion showed nearly normal dynamics during the subseqeunt menstrual cycle.