Endometrial cholinergic secretory responses during estrous cycle, pregnancy and after estrogen and/or progesterone treatment of the guinea-pig

Publisher Website
Google Scholar
Abstract
During the estrous cycle and during pregnancy and after treatment with estrogen and/or progesterone uterine mucus secretory responses were studied as amonount of carbohydrate released from everted guinea pig uteri after transmural nerve stimulation or carbachol administration. In the estrous cycle both stimuli increased secretion by .apprx. 20% except for the late diestrus phase, when no secretory responses were seen. In pregnancy a secretory responses was noted at implantation time. From mid-pregnancy and onwards secretory responses of increasing magnitude were obtained. Secretory responses persisted postpartum. Evidence of an adrenergic inhibitory influence on the neurogenic cholingergic responses during metestrus was noted. Both stimuli increased carbohydrate release by .apprx. 50% above resting level in uteri from animals receiving combined hormone treatment. In uteri of animals receiving estrogen only the increase was .apprx. 20%. No definite secretory response was obtained in uteri from animals receiving progesterone only. Apparently both hormones are necessary for full cholinergic secretory response to nerve stimulation or muscarinic drugs. Muscarinic stimulation of the endometrium may result in mucus secretion during all crucial events during the reproductive cycle. A cholinergic secretory innervation seems to be present at all these times.