Verhandlungen Ärztlicher Gesellschaften

Ohne Zusammenfassung     

Clinical Observations on Chlorothiazide and Rauwolfia in Treatment of Essential Hypertension

To evaluate the antihypertensive effect of a combination of chlorothiazide and Rauwolfia, 26 patients were given chlorothiazide alone for two months and 24 were given Rauwolfia alone for the same period; then 18 patients (10 from the first group and eight from the second) were given both drugs for two months.

Chlorothiazide alone proved to be an effective antihypertensive agent in 35 per cent of patients with mild to moderate hypertension. The number of cases in which the blood pressure decreased to normotensive levels increased when Rauwolfia was added. Results of combined therapy were better when chlorothiazide rather than Rauwolfia was given alone first.     

The regulation of hemopoiesis in long-term bone marrow cultures. II. Stimulation and inhibition of stem cell proliferation

The isolation of a DNA synthesis inhibitor (NBME fraction IV) and stimulator (RBME fraction III) specific for the hemopoietic stem cell (CFU-s) from freshly isolated normal adult and regenerating murine bone marrow, respectively, has been well documented. We have utilized long- term liquid bone marrow cultures in a further analysis of the role of these factors in the regulation of CFU-s proliferation. Our results show that shortly after feeding, at a time when the cultured CFU-s are actively proliferating, high levels of the hemopoietic stem cell proliferation stimulator fraction III can be isolated from the culture medium. In contrast, the presence of essentially noncycling CFU-s found in cultures fed 8-10 days previously correlates with high levels of the hemopoietic stem cell inhibitor fraction IV. These results suggest that a certain balance between these factors determines CFU-s proliferation in the long-term cultures. In support of this, DNA synthesis in actively cycling CFU-s in the long-term cultures is inhibited for at least 3 days by the addition of excess NBME fraction IV (inhibitor). Furthermore, DNA synthesis in noncycling cultured CFU-s is stimulated for at least 5 days by the addition of RBME fraction III (stimulator).     

Regulation of prolactin and somatotropin mRNAs by thyroliberin.

The tripeptide thyroliberin (thyrotropin-releasing hormone, TRH) regulates the levels of cytoplasmic prolactin and growth hormone (somatotropin) mRNAs in a line of functional rat pituitary tumor cells. Intracellular mRNA levels were determined with specific complementary DNA probes in RNA-excess hybridization reactions and independently by two-dimensional gel electrophoretic analysis of the products of mRNA-directed cell-free translation. Prolactin mRNA sequences increased from 1.1 to 4.5% of the cytoplasmic poly(A)containing mRNA within 48 hr after addition of TRH to the medium; in parallel, growth hormone mRNA sequences were decreased. Similar effects on prolactin mRNA levels were observed in cells grown in serum-containing medium or when the cells were maintained in a serum-free medium for 72 hr prior to addition of TRH, suggesting that TRH is responsible for the stimulation of prolactin mRNA levels rather than for exerting a permissive effect for another factor present in serum.