title: Thrombin-induced membrane currents in native Xenopus follicles.
abstract: The presence and properties of thrombin receptors have been investigated in Xenopus Laevis follicles. In follicles, voltage-clamped at -60 mV or -80 mV, sub-micromolar concentrations of thrombin (Thr) induce smooth inward currents carried by chloride ions, which desensitize over tens of minutes. This desensitization is prevented by PKC inhibitors (staurosporine and H7). Responses are inhibited by hirudin. Inconsistent responses can be observed in defolliculated oocytes. Thr responses, readily recorded in hypo-osmotic solution are abolished by perfusion of normal frog "Ringer" or by the addition of 50 mM sucrose. Thus Thr acts on receptors present in the follicular cells triggering the opening of chloride channels by acting on receptors, likely to be located on follicular cells, via a PKC-regulated pathway.
authors: Department of Psychobiology, U.C.I. 92715, USA.
authors: Q T
authors: QT
authors: Nguyen
authors: J
authors: J
authors: Stinnakre
authors: R
authors: R
authors: Miledi
mesh_terms: D000818:Animals; D005260:Female; D007473:Ion Channels / Q000187:drug effects*; D008564:Membrane Potentials / Q000187:drug effects; D008566:Membranes / Q000187:drug effects / Q000378:metabolism; D009865:Oocytes / Q000187:drug effects*; D009997:Osmotic Pressure; D018408:Patch-Clamp Techniques; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism; D013917:Thrombin / Q000494:pharmacology*; D014982:Xenopus laevis
chemical_list: D007473:Ion Channels; D011493:Protein Kinase C; D013917:Thrombin