Effects of arginine- and lysine-vasopressin on phospholipase C activity, intracellular calcium concentration and prostaglandin F-2 alpha secretion inpig endometrial cells

Citation
Gt. Braileanu et al., Effects of arginine- and lysine-vasopressin on phospholipase C activity, intracellular calcium concentration and prostaglandin F-2 alpha secretion inpig endometrial cells, REPRODUCT, 121(4), 2001, pp. 605-612
Citations number
41
Language
INGLESE
art.tipo
Article
Categorie Soggetti
da verificare
Journal title
REPRODUCTION
ISSN journal
1470-1626 → ACNP
Volume
121
Issue
4
Year of publication
2001
Pages
605 - 612
Database
ISI
SICI code
1470-1626(200104)121:4<605:EOAALO>2.0.ZU;2-6
Abstract
Oxytocin and vasopressin are related peptides that have receptors in the ut erus. Species from families other than Suidae produce only arginine-vasopre ssin; in contrast, pigs apparently express both arginine- and lysine-vasopr essin. The aim of this study was to determine whether arginine- or lysine-v asopressin would activate phospholipase C, increase intracellular calcium c oncentration [Ca2+](i) and stimulate PGF(2 alpha) production in enriched cu ltures of stromal, glandular epithelial and luminal epithelial cells from p ig endometrium. Cells were obtained from gilts on day 16 after oestrus by d ifferential enzymatic digestion and sieve separation. After 96 h in culture , the cells were treated with 0 or 100 nmol arginine- or lysine-vasopressin I-1. The responses to 100 nmol oxytocin I-1 and 100 nmol GnRH I-1 were use d as positive and negative controls, respectively. Consistent with previous results, oxytocin stimulated phospholipase C activity (P < 0.05), increase d [Ca2+](i) (P < 0.05) and promoted PGF(2 alpha) secretion (P < 0.05) from stromal and glandular epithelial cells. Activity of phospholipase C, [Ca2+] (i) and PGF(2 alpha) release were also increased (P < 0.05) by arginine-vas opressin in stromal cells, but the responses were less (P < 0.01) than thos e induced by oxytocin. An oxytocin antagonist attenuated the [Ca2+](i) resp onse of stromal cells to both oxytocin and arginine-vasopressin. Sequential treatment of cells with oxytocin and arginine-vasopressin indicated that o xytocin desensitized the response to oxytocin, but arginine-vasopressin did not similarly desensitize the response to oxytocin. In glandular and lumin al epithelial cells, arginine-vasopressin did not stimulate phospholipase C activity, [Ca2+](i) or PGF(2 alpha) secretion. Neither GnRH nor lysine-vas opressin induced phospholipase C activity, increased [Ca2+](i) or stimulate d PGF(2 alpha) production in any endometrial cell type. These results indic ate that oxytocin receptors can bind arginine-vasopressin more readily than they bind lysine-vasopressin. Type 1 vasopressin receptors may also exist in endometrium predominantly on cells other than stromal, glandular epithel ial and luminal epithelial cells, as in previous studies both arginine-vaso pressin and lysine-vasopressin stimulated phospholipase C activity in endom etrial explants to a similar extent as oxytocin.