Effect of the oxytocin antagonist antocin and agonist decomoton on baboon luteal cell production and release of progesterone.
OBJECTIVE
To evaluate the effect of oxytocin, its antagonist antocin, and agonist decomoton on baboon luteal cell P secretion.


METHODS
Prospective study.


METHODS
Academic department of obstetrics and gynecology in a US medical school.


METHODS
Luteal-phased timed corpora lutea (CL) from a cohort of adult cycling baboons (Papio anubis).


METHODS
Dispersed luteal cells from luteal phase baboon CL were cultured and treated with nothing (control), oxytocin (4-400 mU), antocin (4-400 microg), oxytocin with antocin, decomoton (4-400 microg), or oxytocin with decomoton.


METHODS
Basal and hCG (10 U)-stimulated P were measured in the incubate.


RESULTS
Basal P secretion did not change significantly with all peptides studied. The hCG-stimulated P secretion was significantly inhibited by oxytocin (4-400 mU), antocin (4-400 microg), and antocin combined with oxytocin, and with oxytocin, decomoton, and decomoton combined with oxytocin. Antocin (-12%) was less inhibitory than oxytocin (-25% to -22%). Antocin combined with oxytocin enhanced the inhibition to -35% to -39%. Decomoton had stronger (not significant) inhibition than oxytocin. Mean inhibition was 28%-35% with all doses of oxytocin, decomoton, or combined together.


CONCLUSIONS
Although decomoton, an oxytocin agonist inhibited hCG-stimulated luteal cell P secretion in vitro, antocin also acted like an agonist, rather than an antagonist, in inhibiting P secretion.
Department of Obstetrics and Gynecology, West Virginia University School of Medicine, Morgantown, West Virginia 26506-9186, USA. ydawood@hsc.wvu.edu
M Yusoff
MY
Dawood
Firyal S
FS
Khan-Dawood
D000818:Animals; D002478:Cells, Cultured; D005260:Female; D008184:Luteal Cells / Q000378:metabolism*; D010121:Oxytocin / Q000819:agonists* / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010215:Papio; D011374:Progesterone / Q000378:metabolism*
D011374:Progesterone; D010121:Oxytocin