雄激素调节大鼠尿ANG排泄和肾ANG基因的表达

Androgen Regulation of Rat Urine ANG Excretion and Renal ANG mRNA Expression

目的探讨雄激素对肾脏局部ANG合成和排泄的影响。方法用放免法测定血尿中ANG浓度和用Northernblot分析肝肾ANGmRNA含量。结果自第7周起，雄性大鼠尿中ANG量是同龄雌性大鼠和去势大鼠的4倍；雄性大鼠肾ANGmRNA的水平也高于另两组；但血浆ANG和肝ANGmRNA水平三组间无明显差异。成年雄性大鼠去势2周后，尿ANG量显著减少；去势幼鼠皮下给予17－a一甲睾酮3周后，尿排泄ANG增加3倍，同时肾ANGmRNA的表达也增加2倍。结论雄激素调节肾ANGmRNA的表达和尿ANG的排泄。

Objective To determine the regulatory effects of androgen on rat renalagiotensinogen(ANG) production and excretion. Methods Urine and plasma ANG weremeasured and liver and kidney ANG mRNA were analyzed by direct radioimmunoassay andNorthern blot method, respectively. Results The amounts of ANG excreted by male ratsafter the age of 7 weeks was four fold higher than,that by female and castrated rats, andrenal levels of ANG mRNA also was higher in male rats. The levels of plasma ANG and liverANG mRNA, in contrast, showed no significant difference between these three groups at anyage. Castration of adult males caused a significant reduction of urinary ANG after 2 weeks.Consecutive s.c. administration of l7 - α - methyltertostr0ne for 3 weeks in Castrated malesresulted in a three fold increase in the urinary excretion of ANG, as well as a twofoldincrease in the renal expression of ANG mRNA. Conclusion Androgen regulates theexpression of ANG gene and the excretion of ANG from the kidney.