title: Trypsin induces Ca(2+)-activated Cl- currents in X. laevis oocytes.
abstract: The protease trypsin induces Ca(2+)-activated Cl- currents when applied in concentrations as low as 0.1 mg/ml to defolliculated, voltage clamped X. laevis oocytes. The response is dose-dependent and specific, as other proteases (chymotrypsin, Lys-C and Arg-C), or trypsin pretreated with soybean trypsin inhibitor, did not induce currents. Intracellular trypsin injection did not induce responses. The current does not appear to result from proteolytic activation of the endogenous receptor for lysophosphatidic acid, the only known Ca(2+)-mobilizing receptor consistently present in oocytes. These results suggest the presence on the oocyte membrane of a specific receptor for trypsin.
authors.affiliation: Department of Anesthesiology, University of Virginia, Charlottesville 22903.
authors.forename: M E
authors.initials: ME
authors.lastname: Durieux
authors.forename: M N
authors.initials: MN
authors.lastname: Salafranca
authors.forename: K R
authors.initials: KR
authors.lastname: Lynch
mesh_terms: D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D018118:Chloride Channels / Q000187:drug effects / Q000502:physiology*; D002918:Chymotrypsin / Q000494:pharmacology; D004533:Egtazic Acid / Q000494:pharmacology; D004553:Electric Conductivity; D005260:Female; D007700:Kinetics; D008564:Membrane Potentials; D008666:Metalloendopeptidases / Q000494:pharmacology; D009865:Oocytes / Q000502:physiology*; D011956:Receptors, Cell Surface / Q000187:drug effects / Q000502:physiology; D043562:Receptors, G-Protein-Coupled; D049368:Receptors, Lysophosphatidic Acid; D012697:Serine Endopeptidases / Q000494:pharmacology; D014357:Trypsin / Q000494:pharmacology*; D014982:Xenopus laevis
chemical_list: D018118:Chloride Channels; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D049368:Receptors, Lysophosphatidic Acid; D004533:Egtazic Acid; C044499:submandibular proteinase A; D012697:Serine Endopeptidases; D002918:Chymotrypsin; D014357:Trypsin; D008666:Metalloendopeptidases; C039830:peptidyl-Lys metalloendopeptidase; D002118:Calcium