Regulation of electrolyte transport across cultured endometrial epithelial cells by prolactin

Abstract

The effect of prolactin (PRL) on ion transport across the porcine glandular endometrial epithelial cells was studied in primary cell culture using the short-circuit current technique. Addition of 1 mg/ml PRL either to the apical solution or to the basolateral solution produced a peak followed by a sustained increase in Isc, but with a lesser response when PRL was added apically. Basolateral addition of PRL increased the Isc in a concentrationdependent manner with a maximum effect at 1 mg/ml and an effective concentration value of 120 ng/ml. The PRLstimulated Isc was significantly reduced by pretreatment with an apical addition of 5-nitro-2-(3-phenylpropylamino) benzoic acid (200 mM), diphenylamine-2-carboxylic acid (1 mM) or 4,4 0 -diisothiocyanatostilbene-2,2 0 -disulfonic acid (200 mM), Cl K channel blockers, but not by amiloride (10 mM), a Na C channel blocker. In addition, pretreatment with bumetanideK cotransporter inhibitor, in the basolateral solution significantly reduced the PRL-stimulated Isc. Replacement of Cl K or HCO K 3 in the bathing solutions also decreased the Isc response to PRL. Pretreatment of the monolayer with AG490 (50 mM), an inhibitor of JAK2 activity significantly inhibited the PRL-induced increase in Isc. Western blot analysis of the porcine endometrial epithelial cells revealed the presence of short isoform of PRL receptor (PRLR-S) that could be regulated by 17b-estradiol. The results of this investigation showed that PRL acutely stimulated anion secretion across the porcine endometrial epithelial cells possibly through PRLR-S present in both apical and basolateral membranes. The PRL response appeared to be mediated by the JAK2-dependent pathway.

Effects of metoclopramide-induced hyperprolactinemia on the prolactin receptor of murine endometrium

“…In addition, PRL acutely stimulated anion secretion across the porcine endometrial epithelial cells, possibly through the short isoform of the PRL-R present in both apical and basolateral membranes. This pathway may be regulated by 17b-estradiol (14).…”

Laxative properties of aqueous and methanolic extracts of mature stem bark of Neoboutonia velutina Prain (Euphorbiaceae) in rats

“…The colon absorbs Na+ and Cl -ions but secretes K + ions which lead to a retention of water and a concentration of faeces. According to the work completed by Deachapunya et al (2005), the majority of natural laxatives exert their effects on the colonic epithelium by stimulating secretion of Cl -ions and/or by inhibiting absorption of Na + ions, leading to an accumulation of the intestinal fluid as well as an increase of colon motility (Méité et al, 2010). Both extracts increased the distance covered by charcoal, which can be assimilated as an increased intestinal peristalsis in rats (Wintola et al, 2010).…”

Site-specific regulation of ion transport by prolactin in rat colon epithelium

“…chloride transport; potassium transport; electrolyte transport; epithelium PROLACTIN (PRL) HAS BEEN REPORTED to regulate water and electrolyte balance in teleosts, amphibian, and most vertebrates (4,22). PRL receptor and its mRNA have been identified in kidney, intestinal, and other epithelial cells and tissues (8,9,13). In the intestinal epithelial tissues, PRL has previously been shown to increase fluid and NaCl absorption in the rat proximal colon (PC) using everted sac technique (19).…”

“…A recent study has demonstrated that PRL (200 ng/ml) had no direct effect on basal short-circuit current (I sc ), but inhibited the carbachol-stimulated Cl Ϫ secretion in the PC and K ϩ secretion in the distal mouse colon (21). Meanwhile, studies in cultured epithelial cells have reported an enhancing effect of PRL on Cl Ϫ secretion (9,25).…”