Stimulation of Aldosterone Production in vitro by Ammonium Ions

Nature ◽  
1965 ◽  
Vol 206 (4979) ◽  
pp. 92-92 ◽  
Author(s):  
JüRG MüLLER
1965 ◽  
Vol 50 (2) ◽  
pp. 301-309 ◽  
Author(s):  
Jürg Müller

ABSTRACT An extract of human urine, which was previously shown to stimulate aldosterone production by rat adrenal sections, was further purified. Evidence was obtained that its aldosterone-stimulating effect was due to the presence of ammonium ions. Addition of ammonium chloride and of urine extract to the incubation medium caused identical increases in aldosterone production in vitro. In addition to ammonium ions, rubidium and caesium ions also stimulated aldosterone production up to 250% that of control values without a significant effect on corticosterone production. Similar dose-response curves were obtained when increasing concentrations of potassium, ammonium, rubidium and caesium ions were tested. Aldosterone production was maximal at concentrations of 7 mval/1 and was significantly lower at higher concentrations. When ammonium chloride and ACTH were simultaneously added to the incubation medium, the production of aldosterone and of corticosterone was lower than with ACTH alone. On the other hand, the stimulating activity on aldosterone and corticosterone production by »TPN« (NADP) and glucose-6-phosphate was enhanced by the simultaneous addition of ammonium chloride.


1968 ◽  
Vol 59 (1) ◽  
pp. 23-35 ◽  
Author(s):  
Jürg Müller ◽  
Walter H. Ziegler

ABSTRACT The dialysable fraction of rat serum, which was previously shown to stimulate aldosterone production in rat adrenal sections, was chromatographed on Sephadex G-25. Fluorescence spectra indicated that a 5-hydroxyindole derivative was present in the active eluate fraction. The aldosterone-stimulating activity of serum dialysate had a similar retention volume to serotonin and 5-hydroxytryptophan, but was separated from other indole derivatives. Addition of small amounts of pure serotonin to the incubation medium led to a significant and dose-dependent increase of aldosterone and deoxycorticosterone production but did not affect corticosterone production. At higher concentrations, 5-methoxytryptamine, bufotenine and 5-hydroxytryptophan also stimulated aldosterone biosynthesis, whereas a number of other substances chemically or pharmacologically related to serotonin were found to be inactive. Two different serotonin antagonists completely blocked the aldosterone-stimulating effects of serotonin and rat serum but did not influence aldosterone stimulation by ACTH. Serotonin stimulated the incorporation of tritiated cholesterol into aldosterone but not the incorporation of tritiated pregnenolone, indicating that it acts on the conversion of cholesterol to pregnenolone.


1985 ◽  
Vol 54 (04) ◽  
pp. 799-803 ◽  
Author(s):  
José Luís Pérez-Requejo ◽  
Justo Aznar ◽  
M Teresa Santos ◽  
Juana Vallés

SummaryIt is shown that the supernatant of unstirred whole blood at 37° C, stimulated by 1 μg/ml of collagen for 10 sec, produces a rapid generation of pro and antiaggregatory compounds with a final proaggregatory activity which can be detected for more than 60 min on a platelet rich plasma (PRP) by turbidometric aggregometry. A reversible aggregation wave that we have called BASIC wave (for Blood Aggregation Stimulatory and Inhibitory Compounds) is recorded. The collagen stimulation of unstirred PRP produces a similar but smaller BASIC wave. BASIC’s intensity increases if erythrocytes are added to PRP but decreases if white blood cells are added instead. Aspirin abolishes “ex vivo” the ability of whole blood and PRP to generate BASIC waves and dipyridamole “in vitro” significantly reduces BASIC’s intensity in whole blood in every tested sample, but shows little effect in PRP.


1962 ◽  
Vol 39 (3) ◽  
pp. 423-430
Author(s):  
H. L. Krüskemper ◽  
F. J. Kessler ◽  
E. Steinkrüger

ABSTRACT 1. Reserpine does not inhibit the tissue respiration of liver in normal male rats (in vitro). 2. The decrease of tissue respiration of the liver with simultaneous morphological stimulation of the thyroid gland after long administration of reserpine is due to a minute inhibition of the hormone synthesis in the thyroid gland. 3. The morphological alterations of the thyroid in experimental hypothyroidism due to perchlorate can not be prevented with reserpine.


1974 ◽  
Vol 77 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Gustav Wägar

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.


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