Effects of varying gonadotrophin dose and timing on antrum formation and ovulation efficiency of mouse follicles in vitro.
BACKGROUND
This study tested factors affecting mouse follicle growth in vitro, to determine end-points marking follicle function in vitro.


METHODS
Pre-antral follicles (mean 137 microm) from B6CBF1 mice were cultured in a substrate-adherent system for < or = 14 days. FSH (0-1000 mIU/ml) day of HCG (1.5 IU/ml days 9-14) protein supplement [fetal calf serum (FCS) (x2) mouse serum (x2) hypogonadal (hpg) mouse serum or human serum albumin (HSA)] were varied. Follicle survival timing of antrum formation incidence of ovulation within 16,24,40,48 h of HCG oocyte growth were assessed.


RESULTS
FSH (100 mIU/ml) produced the best antral development (P < 0.001 versus 10 and 1000 mIU/ml). Antra were observed from day 5. Transient antra formed occasionally in the absence of FSH. By 14 days significant senescence had occurred (P < 0.001) but the proportion of follicles ovulating within 16 h of HCG declined from day 9 onwards indicating this to be a more sensitive marker of follicle responsiveness. Optimal growth occurred in 5% FCS (x2) or hpg mouse serum although fewer follicles ovulated in hpg serum (P < 0.05). No normal growth occurred in normal mouse serum (x2) or HSA. Oocytes grew to full size within 9 days with 100 mIU/ml FSH FCS.


CONCLUSIONS
These data provide sensitive end-points for assessing follicle growth in vitro.
Mitchell
Leila M
LM
Department of Biological Sciences University of Warwick Coventry CV4 7AL UK.
Kennedy
C Richard
CR
Hartshorne
Geraldine M
GM
D000818:Animals; D001790:Blood Physiological Phenomena; D048429:Cell Size / Q000187:drug effects; D006063:Chorionic Gonadotropin / Q000008:administration & dosage / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005640:Follicle Stimulating Hormone / Q000008:administration & dosage* / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D051379:Mice; D008815:Mice, Inbred Strains; D009865:Oocytes / Q000166:cytology; D009994:Osmolar Concentration; D006080:Ovarian Follicle / Q000187:drug effects* / Q000502:physiology*; D010060:Ovulation / Q000187:drug effects*; D012709:Serum Albumin / Q000494:pharmacology
D006063:Chorionic Gonadotropin; D012709:Serum Albumin; D005640:Follicle Stimulating Hormone