Distribution of P2X receptor subtypes in the rat female reproductive tract at late pro-oestrus/early oestrus

Abstract

Using immunohistochemistry techniques, we have examined the female reproductive organs of the rat in late pro-oestrus/early oestrus for the presence of purine nucleotide P2X1-7 receptors. In contrast to the male genital organs and the urinary tract, P2X1 receptors were present weakly, if at all, on smooth muscle membranes, except in blood vessels, whereas P2X2 immunoreactivity in smooth muscle was present in ovary and uterus as well as in blood vessels. Neither P2X1 nor P2X2 receptors were present in fallopian tubes. P2X5 receptors were seen in the differentiating cell layers of the stratified squamous vaginal epithelium and also in the very early stages of ovarian follicular development; P2X6 receptors were present in secondary follicles. P2X7 receptors, markers for programmed cell death, were present in the keratinised vaginal epithelium and also in the exfoliating superficial endometrial cells. The possible biological significance of these signalling molecules in the female reproductive tract is discussed.

Changes in expression of P2X1 receptors and connexin 43 in the rat myometrium during pregnancy

“…Very weak P2X 1 receptor immunoreactivity of the nonpregnant rat uterus has been described (23), and P2X 1 receptors have been identified in the uterine epithelial cells in nonpregnant rats and during early pregnancy (38,39). Adenosine 5 0 -triphosphate causes direct contraction of rodent myometrial smooth muscle cells in the nonpregnant (40)(41)(42)(43) and pregnant myometrium (44,45), probably acting via P2X 1 receptors.…”

“…Preabsorption of the P2X 1 receptor antibody with an excess of the synthetic peptide eliminated immunoreactivity (23).…”

P2X receptor immunoreactivity in the male genital organs of the rat

“…Immunoblotting studies have shown that anti-P2X 1-7 antibodies specifically recognise the recombinant receptors expressed in CHO-K1 cells (Oglesby et al 1999). Preabsorption of the antibodies with excess of the appropriate synthetic peptide used for generation of the antibodies eliminated immunoreactivity (see Xiang et al 1998aXiang et al , 1998bGröschel-Stewart et al 1999a;Bardini et al 2000).…”

Purinergic Signalling in the Reproductive System

“…Data in the rat suggested that the P2X 5 and P2X 7 receptors play a role in the physiological turnover of continuously regenerating cells (Gröschel-Stewart et al, 1999;Bardini et al, 2000). In females, the P2X 4 receptor is involved in the regulation of tight junctional resistance and transepithelial transport across the vaginal epithelium, and possibly in the acidification of the luminal fluid, similar to effects observed in the endometrium and cervix (discussed above).…”

“…Non-keratinizing squamous stratified epithelial cells of the vagina, and keratinizing squamous stratified epithelial cells of the vulva express P2X 4 (Gorodeski, 2002a), P2X 5 (Gröschel-Stewart et al, 1999Bardini et al, 2000), and P2X 7 receptors (Li et al, 2006a(Li et al, , 2007. Data in the rat suggested that the P2X 5 and P2X 7 receptors play a role in the physiological turnover of continuously regenerating cells (Gröschel-Stewart et al, 1999;Bardini et al, 2000).…”