Effect of preantral follicle isolation technique on in-vitro follicular growth, oocyte maturation and embryo development in mice.
BACKGROUND
The use of mechanical and enzymatic techniques to isolate preantral follicles before in-vitro culture has been previously described. The aim of this study was to assess the effect of the isolation procedure of mouse preantral follicles on their subsequent development in vitro.


METHODS
Follicles were isolated either mechanically or enzymatically and cultured using an individual non-spherical culture system. Follicular development and steroidogenesis, oocyte in-vitro maturation and embryo development were assessed for both groups.


RESULTS
After 12 days of culture, follicles isolated mechanically had a higher survival rate but a lower antral-like cavity formation rate than follicles isolated enzymatically. Enzymatic follicle isolation was associated with a higher production of testosterone and estradiol compared with mechanical isolation. A stronger phosphatase alkaline reaction was observed after enzymatic isolation, suggesting that follicles isolated enzymatically had more theca cells than those isolated mechanically. However, both isolation techniques resulted in similar oocyte maturation and embryo development rates.


CONCLUSIONS
Enzymatic follicular isolation did not affect theca cell development. Follicular steroidogenesis was enhanced after enzymatic isolation but the developmental capacity of oocytes was comparable to that obtained after mechanical isolation.
Demeestere
I
I
Research Laboratory on Human Reproduction, Erasme Hospital, French Speaking Free University of Brussels, Route de Lennik 808, 1070 Brussels, Belgium. idemeest@ulb.ac.be
Delbaere
A
A
Gervy
C
C
Van Den Bergh
M
M
Devreker
F
F
Englert
Y
Y
D000818:Animals; D016922:Cellular Senescence / Q000502:physiology; D017364:Collagenases; D046508:Culture Techniques; D003851:Deoxyribonucleases; D004210:Dissection; D004622:Embryo, Mammalian / Q000502:physiology*; D005314:Embryonic and Fetal Development; D005260:Female; D005307:Fertilization in Vitro; D006728:Hormones / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D009865:Oocytes / Q000502:physiology*; D006080:Ovarian Follicle / Q000166:cytology / Q000502:physiology*; D013799:Theca Cells / Q000166:cytology; D013997:Time Factors
D006728:Hormones; D003851:Deoxyribonucleases; D017364:Collagenases