Effect of a GnRH analogue on rat granulosa cell lactate production in vitro.
The effect of a GnRH analogue [D-Ala6, des-Gly10-NH2)-GnRH-ethylamide,GnRHa) on granulosa and cumulus cell glycolysis in presence or absence of FSH was studied. Cumulus complexes and granulosa cells from PMSG-treated rats were cultured in Eagle's minimal essential medium (MEM) for a period of 72 h. Media were changed at 24 and 48 h and lactate content was assayed by fluorimetry. GnRHa alone stimulated lactate production in granulosa cells. GnRH combined with FSH increased lactate production in granulosa cells during the 0-24 h period and decreased it during the 48-72 h period as compared to FSH alone. GnRHa did not stimulate lactate production in cumulus complexes during 72 h culture in MEM, while FSH did. In a less complex culture medium, BMOC, GnRHa caused a small increase in lactate production and slightly enhanced the FSH effect. In conclusion, GnRHa has a direct stimulatory effect on granulosa cell glycolysis. GnRHa also modulates the FSH stimulation of granulosa cells biphasically, i.e. early enhancement (0-24 h) and late inhibition (48-72 h). GnRHa has no consistent direct effects on cumulus cell glycolysis.
D000818:Animals; D002469:Cell Separation; D002478:Cells, Cultured; D003470:Culture Media; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D006019:Glycolysis / Q000187:drug effects; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D006064:Gonadotropins, Equine / Q000494:pharmacology; D006107:Granulosa Cells / Q000378:metabolism*; D007773:Lactates / Q000096:biosynthesis*; D051381:Rats; D011919:Rats, Inbred Strains
D003470:Culture Media; D006064:Gonadotropins, Equine; D007773:Lactates; D007987:Gonadotropin-Releasing Hormone; C010661:surfagon; D005640:Follicle Stimulating Hormone