Changes with age and sex in levels of plasma and ovarian or testicular endothelin-1 in rats.
Mammalian ovaries and testes contain various intragonadal peptides necessary to control gonadal function. Effects of aging and sex on total plasma and ovarian or testicular endothelin-1 (ET-1) levels were studied in female and male rats aged 4-140 days. At 2 weeks, plasma ET-1 levels were 2.69 +/- 0.09 and 2.41 +/- 0.03 pg/ml (mean +/- SEM; n = 10) in the female and male, respectively. After a temporary decrease, mean ET-1 concentrations increased at 10 weeks and again decreased at 20 weeks in the female, thereafter revealing a plateau, whereas the ET-1 concentrations gradually decreased in the male. In adult females, plasma ET-1 levels were 3.7-fold higher than male levels. Ovarian ET-1 levels gradually increased after birth to 2 weeks, then decreased, and again increased at 3 weeks. Thereafter they gradually decreased, showing a plateau after 10 weeks. In contrast, testicular ET-1 levels gradually decreased after birth. This difference is parallel to but much larger than the sex difference in ovarian or testicular ET-1. Gonadal ET-1 showed a very different ontogeny.
Otani
S
S
Department of Gynecology, Kinu Medical Association Hospital, Ibaraki, Japan.
Usuki
S
S
Kubo
T
T
D000327:Adsorption; D000375:Aging / Q000378:metabolism*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D019332:Endothelin-1 / Q000097:blood / Q000378:metabolism*; D004971:Estrus / Q000378:metabolism; D005260:Female; D007124:Immunoenzyme Techniques; D008297:Male; D010053:Ovary / Q000254:growth & development* / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012727:Sex Characteristics; D013737:Testis / Q000254:growth & development* / Q000378:metabolism*
D019332:Endothelin-1