Effect of L-tyrosine on 3beta-HSD activity of rat luteal cells in vitro.
- Author:
Hui-ping WANG
1
;
Jiang NI
;
Zhi-ping CHENG
Author Information
- Publication Type:Journal Article
- MeSH: 3-Hydroxysteroid Dehydrogenases; metabolism; Animals; Cells, Cultured; Female; Luteal Cells; drug effects; enzymology; Rats; Rats, Wistar; Tyrosine; pharmacology
- From: Chinese Journal of Applied Physiology 2004;20(2):190-193
- CountryChina
- Language:Chinese
-
Abstract:
AIMTo study the effects of L-tyrosine on 3beta-HSD activity of rat luteal cells in vitro.
METHODSLuteal cells were isolated from ovary tissues of female rats pretreated with PMSG and hCG. Luteal cells were cultured with 95% oxygen and 5% carbon dioxide in 37 degrees C. 3beta-HSD activity was measured by radioimmunoassay (RIA).
RESULTS(1) 0.2 mmol x L(-1) and 2.0 mmol x L(-1) L-tyrosine significantly inhibited 3beta-HSD activity. (2) 0.2 mmol x L(-1) L-tyrosine exerted different effects on 3beta-HSD activity at different concentrations of pregnenolone (Ph). It increased 3beta-HSD activity at 0.1 micromol x L(-1) and 1 micromol x L(-1) of Pn concentration. With further increase in the concentration of Pn to 100 micromol x L(-1), the stimulating effect of L-tyrosine was switched to suppression effect. (3) L-tyrosine and L-tyrosine hydrazide both inhibited 3beta-HSD activity induced by hCG.
CONCLUSIONL-tyrosine affects 3beta-HSD activity of rat luteal cells in vitro. L-tyrosine and tyrosine hydrazide inhibits hCG induced 3beta-HSD activity.