In order to elucidate the effect of stress on reproductive
hormones, the present study was designed to investigate the effect of
adrenocorticotropic hormone (
ACTH) on the plasma levels of
cortisol,
progesterone, oestradiol-17 beta and
prostaglandin F2 alpha metabolite in ovariectomized gilts.
Ovariectomy and cannulation of the jugular vein were performed within 1 week of oestrous detection, under general anaesthesia. Approximately 1 week after surgery, two gilts were each administered
ACTH (
Synacthen Depot) intravenously, at a dose of 0.01 mg/kg
body weight, and one gilt was given
saline solution (5 ml). The reverse was performed on the following day. The administration of
ACTH was followed by a concomitant elevation of
cortisol,
progesterone and
prostaglandin F2 alpha metabolite but not of oestradiol-17 beta. Peak
cortisol,
progesterone and
prostaglandin F2 alpha metabolite levels were reached at 80 +/- 10.0, 80 +/- 10.0 and 46.6 +/- 13.3 min after
ACTH administration and the durations of the peaks were 181.8 +/- 19.8, 308.1 +/- 49.7 and 181.8 +/- 7.9 min, respectively. The total area under the curve for
cortisol,
progesterone and
prostaglandin F2 alpha metabolite was significantly higher in the
ACTH than in the control group. The present results indicate that during stress,
cortisol,
progesterone and
prostaglandin F2 alpha levels are elevated while the level of oestradiol-17 beta is less affected. It can be concluded that the administration of
ACTH to ovariectomized gilts, results in the elevation of
cortisol,
progesterone and
prostaglandin F2 alpha metabolite but not of oestradiol-17 beta.