Browsing by Author "Hermoso, M"

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    Basic aspects of oviduct function
    (PARTHENON PUBLISHING GROUP LTD, 1997) Croxatto, HB; Ortiz, ME; Villalon, M; Cardenas, H; Imarai, M; Hermoso, M; Velasquez, L; Orihuela, P; Coutifaris, C; Mastroianni, L
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    ClC-3 is a fundamental molecular component of volume-sensitive outwardly rectifying Cl- channels and volume regulation in HeLa cells and Xenopus laevis oocytes
    (2002) Hermoso, M; Satterwhite, CM; Andrade, YN; Hidalgo, J; Wilson, SM; Horowitz, B; Hume, JR
    Volume-sensitive osmolyte and anion channels (VSOACs) are activated upon cell swelling in most vertebrate cells. Native VSOACs are believed to be a major pathway for regulatory volume decrease (RVD) through efflux of chloride and organic osmolytes. ClC-3 has been proposed to encode native VSOACs in Xenopus laevis oocytes and in some mammalian cells, including cardiac and vascular smooth muscle cells. The relationship between the ClC-3 chloride channel, the native volume-sensitive osmolyte and anion channel (VSOAC) currents, and cell volume regulation in HeLa cells and X. laevis oocytes was investigated using ClC-3 antisense. In situ hybridization in HeLa cells, semiquantitative and real-time PCR, and immunoblot studies in HeLa cells and X. laevis oocytes demonstrated the presence of ClC-3 mRNA and protein, respectively. Exposing both cell types to hypotonic solutions induced cell swelling and activated native VSOACs. Transient transfection of HeLa cells with ClC-3 antisense oligonucleotide or X. laevis oocytes injected with antisense cRNA abolished the native ClC-3 mRNA transcript and protein and significantly reduced the density of native VSOACs activated by hypotonically induced cell swelling. In addition, antisense against native ClC-3 significantly impaired the ability of HeLa cells and X. laevis oocytes to regulate their volume. These results suggest that ClC-3 is an important molecular component underlying VSOACs and the RVD process in HeLa cells and X. laevis oocytes.
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    Platelet activating factor increases ciliary activity in the hamster oviduct through epithelial production of prostaglandin E2
    (2001) Hermoso, M; Barrera, N; Morales, B; Pérez, S; Villalón, M
    We investigated the signal transduction mechanisms associated with an increase in ciliary beat frequency (CBF) produced by platelet activating factor (PAF) in oviductal ciliated cell cultures. In the range of concentrations similar to that produced by preimplantation embryos, PAF increased the CBF in a dose-dependent manner. The addition of PAF and prostaglandin E-2 (PGE,) to the cultures produced a synergic increase of ciliary beating, suggesting that PAF and PGE(2) signal transduction pathways may be associated. To demonstrate this hypothesis, cyclooxygenase-2 (COX-2) was selectively blocked by a specific inhibitor, NS-398, and the PAF-induced CBF increase was abolished. Moreover, a phospholipase A2 (PLA(2)) inhibitor, AACOCF3, blocks the PAF-induced CBF increase. PGE(2) production by oviductal epithelial cells is stimulated by PAF, and WEB-2086, a PAF-receptor blocker, specifically blocks the PAF-induced PGE(2) production. Using the fluorescent indicator fura-2, we measured the effect of PAF on intracellular Ca2+ concentration ([Ca2+](i)) in individual ciliated cells. PAF induced a transient increase of [Ca2+](i) that was blocked by WEB-2086 or by removal of extracellular Ca2+. We propose a mechanism for PAF-mediated signal transduction in the ciliated cells of the oviductal epithelium. Minimal doses of PAF trigger Ca2+ mobilization in tandem with increased PLA(2) activity and a COX-2-mediated increase in PGE(2). Local PGE(2) production by the oviductal mucosa suggests the presence of an autocrine loop controlling ciliary activity.
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    Preimplantational hamster embryos produce prostaglandin E(2) and platelet activating factor in vitro
    (SOC STUDY REPRODUCTION, 1996) Hermoso, M; Magness, RR; Bavister, B; Villalon, M
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    Regulation of smooth muscle activity in the oviduct by sex hormones
    (CAMBRIDGE UNIV PRESS, 2000) Villalon, MJ; Martinez, S; Hermoso, M; Saez, JC
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    Smooth muscle activity in the oviduct is regulated by sexual hormones.
    (SOC STUDY REPRODUCTION, 1996) Villalon, M; Budinich, M; Hermoso, M; Aguilera, J; Saez, JC