Two injections of hCG in dose of 2000 IU were administered ic an interval of 96hours,and venous blood samples were drawn at 0,1,2,3,4,6,24,48,72 and 96 hr fortestosterone determination.A biphasic curve of testosterone...Two injections of hCG in dose of 2000 IU were administered ic an interval of 96hours,and venous blood samples were drawn at 0,1,2,3,4,6,24,48,72 and 96 hr fortestosterone determination.A biphasic curve of testosterone release was found in normaladult men(n=4),patients with Klinefelter syndrome(n=10)and patients withhypogonadism due to pituitary tumor(n= 8),respectively,but not in prepubertal boys(n=4)and patients with IHH(n = 9).Only after the second loading of hCG the firstpeak of testosterone secretion emerged in the latter two groups.The second peak valuesafter the second injection of hCG were significantly greater than those after the first injection in all groups. Whereas the maximal increments of the second peak were much lowerin normal adult men and patients with Klinefelter syndrome than those in other 3 groups.It was suggested that(1)the first peak of testosterone secretion was depending upon theprevious exposure to high concentration of hCG or LH;(2)repeated administration ofhCG had a self-priming effect on testosterone release,and(3)the desensitization ofLeydig cells existed after a single injection of hCG and its removal was incomplete afteran intermission of 96 hours.展开更多
文摘Two injections of hCG in dose of 2000 IU were administered ic an interval of 96hours,and venous blood samples were drawn at 0,1,2,3,4,6,24,48,72 and 96 hr fortestosterone determination.A biphasic curve of testosterone release was found in normaladult men(n=4),patients with Klinefelter syndrome(n=10)and patients withhypogonadism due to pituitary tumor(n= 8),respectively,but not in prepubertal boys(n=4)and patients with IHH(n = 9).Only after the second loading of hCG the firstpeak of testosterone secretion emerged in the latter two groups.The second peak valuesafter the second injection of hCG were significantly greater than those after the first injection in all groups. Whereas the maximal increments of the second peak were much lowerin normal adult men and patients with Klinefelter syndrome than those in other 3 groups.It was suggested that(1)the first peak of testosterone secretion was depending upon theprevious exposure to high concentration of hCG or LH;(2)repeated administration ofhCG had a self-priming effect on testosterone release,and(3)the desensitization ofLeydig cells existed after a single injection of hCG and its removal was incomplete afteran intermission of 96 hours.
