Physiological roles of androgens in male infants during the first few months of life.
Project/Area Number |
60570430
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
Pediatrics
|
Research Institution | Yamanashi Medical college |
Principal Investigator |
OHYAMA KENJI Dept. of Pediatr. Yamanashi Medical College, 医学部, 講師 (80051861)
|
Co-Investigator(Kenkyū-buntansha) |
赤岡 賢治 山梨医科大学, 医学部・小児科学, 医員
HIGASHIDA KOHSUKE Dept. of Pediatr. Yamanashi Medical College, 医学部・小児科学, 助手 (60173142)
FUJIMOTO MASATOSHI Dept. of Pediatr. Yamanashi Medical College, 医学部・小児科学, 助手 (20156912)
AKAOKA KENJI Dept. of Pediatr. Yamanashi Medical College (80051861)
|
Project Period (FY) |
1985 – 1986
|
Project Status |
Completed (Fiscal Year 1986)
|
Budget Amount *help |
¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 1986: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1985: ¥1,100,000 (Direct Cost: ¥1,100,000)
|
Keywords | Testosterone / Dihydrotestosterone / 5 <alpha> -reductase / Aromatase / ソマトメジン-C |
Research Abstract |
We have previously reported that the hypothalamo-pituitary-gonadal axis of male infants transiently activated during the first months of life. As an extension of our work, testosterone(T), dihydrotestosterone(DHT), somatomedin-c(Sm-C),and sex hormone binding globulin binding capacity(SHBG-C) were measured in serum samples, and 5 <alpha> -reductase activity, aromatase activity, DHT-receptor binding, and Sm-C production rate were assayed in cultured human skin fibroblasts obtained from newborn infants, prepubertal boys and male adults. The following results were obtained. 1. In male infants during first 4 months of age, serum concentration of DHT were as high as those in male adults, and the ratio of DHT/T was significantly high compared to adults(p <0.01). Serum SHBG-C increased in early infancy, but decreased in puberty. 2. There were no agedependent differences in 5 <alpha> -reductase activity and DHT-receptor binding between newborn infants and adults. Aromatase activity was significantly lower in newborn infants and prepubertal boys than in male adults(p < 0.05). 3. The in vitro dissociation rate of DHT-receptor complex in newborn infants was similar to that in adults. 4. Sm-C production rate in fibloblasts was suppressed by T in dose dependent fashion( <10^(-9)> - <10^(-7)> M) These findings suggest that T and DHT secretion during early infancy play some roles, not on early growth spurt, but on maturation of hypothalamo-pituitary-gonadal unit.
|
Report
(1 results)
Research Products
(6 results)