ISSN:
0148-7280
Keywords:
oocyte
;
androgen
;
in vitro maturation
;
pig
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
Notes:
Recent work has shown that 19-norandrostenedione is a major steroidal component of porcine follicular fluid; however, little is known about its role(s) in the regulation of follicular function. This study was designed to examine the effect of 19-norandrostenedione on porcine oocyte maturation in vitro. Oocyte-cumulus complexes were isolated from medium (3-6-mm diameter)-sized prepubertal pig follicles and incubated for 12 h in medium with or without dibutyryl cyclic AMP ((Bu)2cAMP, 1 mM) with or without testosterone (5 x 10-7 M) or 19-norandrostenedione (5 x 10-7 M). In medium alone, 70.8% of oocytes spontaneously resumed meiosis as evidenced by the occurrence of germinal vesicle breakdown. Oocyte maturation was inhibited by (Bu)2cAMP (44.6% of oocytes matured). Although neither steroid alone affected maturation, both testosterone and 19-norandrostenedione enhanced the effect of (Bu)2cAMP (22.5 and 19.6%, respectively, resumed meiosis).The effects of testosterone and 19-norandrostenedione on (Bu)2cAMP-inhibited oocyte maturation were dose dependent and there was no significant difference between the actions of the steroids. The effect of 19-norandrostenedione was reversible and dependent on the presence of an intact cumulus. Hydroxyflutamide (SCH-16423), a nonsteroidal compound known to block androgen receptors, abolished the effects of both testosterone and 19-norandrostenedione on germinal vesicle breakdown, indicating that the actions of these steroids are truly androgenic.The results of this study suggest that 19-norandrostenedione may be of physiological importance in the regulation of porcine oocyte maturation.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrd.1120130210
