酪氨酸单用及合并RU486对小鼠生殖功能的影响及作用机理

EFFECTS OF TYROSINE ALONE AND TYROSINE IN COMBINATIONWITH RU486 ON EARLY PREGNANCY IN MICE AND THE MECHANISM OF ACTION

摘要: 用小鼠抗早孕实验及体外大鼠黄体细胞培养的方法,研究酪氨酸单用及酪氨酸与已知抗生育药RU486合并用药对小鼠早期妊娠的影响及作用机制。结果表明,酪氨酸与RU486合用有协同抗早孕作用。进一步的机理研究发现,酪氨酸170mg·kg^-1·5d可使早孕小鼠血清孕酮水平显著降低;酪氨酸50μg·mL^-1与(+)PG05合用;对抑制大鼠黄体细胞孕酮的基础分泌有协同作用,并能显著抑制hCG诱导的大鼠黄体细胞孕酮的分泌。结果提示:降低孕酮分泌可能是酪氨酸抗生育作用的途径之一。

Abstract: Treatment with tyrosine at the dosage of 85 mg·kg^-1 on day 6～8 of gestation did not have significant effect to terminate early pregnancy in mice. Tyrosine combined with RU486 was shown to have a synergistic effect to terminate early pregnancy. Tyrosine 170 mg·kg^-1 on day 6～10 of gestation significantly decreased the concentration of serum progesterone in early pregnant mice. Further study with luteal cells in rats showed that tyrosine 50 μg·ml^-1 inhibited hCG-induced progesterone production when used alone, and inhibited basal production when used together with (+)PG05. These results suggest that the inhibiting effect of tyrosine on steroidogenesis may contribute to the termination of early pregnancy.