Plasma prostaglandin E2 (PGE2), prostaglandin F2-alpha (PGF2-alpha), and sex steroid hormones (progesterone, androgens, and 17-beta-estradiol) were determined in the female crested newt, Triturus carnifex, during the annual reproductive cycle. In vivo experiments were carried out to study the effects of PGE2 and PGF2-alpha on plasma sex steroid hormones during prereproduction, reproduction, and postreproduction; simultaneously, in vitro experiments were performed to study the effects of these two prostaglandins on sex steroid hormones ovarian release. The effects of one week's captivity on PGE2, PGF2-alpha and sex steroid hormones were also evaluated. The PGE2 plasma level was low from October to December, then it rapidly increased to peak in March, after which it soon fell to reach its minimum value in May. Plasma PGF2-alpha and sex steroid hormones showed similar trends to those found in previous studies. From December to April, the PGE2 plasma values were negatively correlated to those of PGF2-alpha and positively to those of androgens; PGF2-alpha plasma values were positively correlated to those of estradiol. PGE2 in vivo treatment increased plasma progesterone and decreased 17-beta-estradiol in April, while PGF2-alpha induced the opposite effects in the same month; PGE2 increased androgens in January and March, and PGF2-alpha increased androgens in April. The in vitro experiments were in agreement. These results suggest that PGE2 and PGF2-alpha play opposite role(s) in the reproductive processes of the female Triturus carnifex. PGE2 could be involved in the reproduction processes through androgen secretion, while PGF2-alpha in the ending of reproduction through estradiol increase
A POSSIBLE INVOLVEMENT OF PROSTAGLANDIN-E2 IN THE REPRODUCTION OF FEMALE CRESTED NEWT, TRITURUS-CARNIFEX
GOBBETTI, Anna;ZERANI, Massimo;
1992-01-01
Abstract
Plasma prostaglandin E2 (PGE2), prostaglandin F2-alpha (PGF2-alpha), and sex steroid hormones (progesterone, androgens, and 17-beta-estradiol) were determined in the female crested newt, Triturus carnifex, during the annual reproductive cycle. In vivo experiments were carried out to study the effects of PGE2 and PGF2-alpha on plasma sex steroid hormones during prereproduction, reproduction, and postreproduction; simultaneously, in vitro experiments were performed to study the effects of these two prostaglandins on sex steroid hormones ovarian release. The effects of one week's captivity on PGE2, PGF2-alpha and sex steroid hormones were also evaluated. The PGE2 plasma level was low from October to December, then it rapidly increased to peak in March, after which it soon fell to reach its minimum value in May. Plasma PGF2-alpha and sex steroid hormones showed similar trends to those found in previous studies. From December to April, the PGE2 plasma values were negatively correlated to those of PGF2-alpha and positively to those of androgens; PGF2-alpha plasma values were positively correlated to those of estradiol. PGE2 in vivo treatment increased plasma progesterone and decreased 17-beta-estradiol in April, while PGF2-alpha induced the opposite effects in the same month; PGE2 increased androgens in January and March, and PGF2-alpha increased androgens in April. The in vitro experiments were in agreement. These results suggest that PGE2 and PGF2-alpha play opposite role(s) in the reproductive processes of the female Triturus carnifex. PGE2 could be involved in the reproduction processes through androgen secretion, while PGF2-alpha in the ending of reproduction through estradiol increaseI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
