Gonadotropin regulation of inhibin alpha-subunit mRNA and immunoreactive protein in cultured chicken granulosa cells.
Gonadotropin regulation of the inhibin alpha-subunit was investigated in chicken granulosa cell cultures. Granulosa layers were isolated from the F(1) and F(3) + F(4) follicles from three to four hens, pooled according to size, dispersed, and cultured (n = 3 replications for each experiment). In Experiments 1 and 2 either ovine LH or FSH was added to the cultures at doses of 0, 5, and 25 ng/ml. The cultures were terminated at 4, 24, and 48 h after plating. For both follicle sizes the expression of mRNA for the inhibin alpha-subunit was less (P < 0.05) at 24 and 48 h in untreated cells than in those treated with both doses of LH. Expression of the mRNA for the inhibin alpha-subunit was significantly increased only by the 25 ng/ml dose of FSH and only in the F(1) follicle at 24 and 48 h compared to the untreated cells. After 48 h of culture, immunoreactive alpha-subunit protein accumulation was greater for both follicle types in the media of cells treated with the highest dose of LH and FSH than in the media from untreated cells. In Experiment 3, doses of 0, 5, 25, or 50 ng/ml of either LH or FSH were added to F(1) and F(3) + F(4) granulosa cells. All cultures were terminated at 48 h. LH and FSH increased the expression of the mRNA and immunoreactive protein for the inhibin alpha-subunit equally in a time-dependent manner. These experiments indicate that gonadotropins enhance the expression of both the mRNA and the protein for the inhibin alpha-subunit in chicken granulosa cells.
Davis
A J
AJ
Department of Animal Science, Cornell University, Ithaca, New York 14853, USA.
Brooks
C F
CF
Johnson
P A
PA
D000818:Animals; D002645:Chickens / Q000235:genetics*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006107:Granulosa Cells / Q000378:metabolism*; D007265:Inhibins / Q000235:genetics* / Q000378:metabolism; D007986:Luteinizing Hormone / Q000494:pharmacology*; D006080:Ovarian Follicle / Q000502:physiology; D011374:Progesterone / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*
D012333:RNA, Messenger; D011374:Progesterone; D007265:Inhibins; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone