title: Effects of cytochalasin B on the response of toad urinary bladder to vasopressin.
abstract: A combined physiological and morphological study of the effects of cytochalasin B (CB) on the toad urinary bladder has been carried out. CB inhibits the hydro-osmotic response to vasopressin without altering basal water permeability or diffusion, or the increase in (3)H(2)O diffusion observed after hormone addition. Although CB increases [(22)Na]-, [(36)Cl]-, and [(14)C]urea fluxes, and decreases transepithelial potential, no alteration in basal short-circuit current, the vasopressin-induced increase in this parameter, or [(14)C]inulin permeability occurs. In the absence of hormone, CB does not markedly alter the structure of the toad bladder. However, in the presence of vasopressin, CB induces the formation of large intracellular vacuoles. These results suggest a possible coupling of solute and water movement across the tissue.
mesh_terms: D000818:Animals; D001001:Anura; D002250:Carbon Radioisotopes; D002713:Chlorine; D000242:Cyclic AMP; D003571:Cytochalasin B / Q000494:pharmacology*; D004058:Diffusion; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D005260:Female; D066298:In Vitro Techniques; D007328:Insulin; D008854:Microscopy, Electron; D009994:Osmolar Concentration; D010539:Permeability; D011868:Radioisotopes; D012964:Sodium; D012975:Sodium Isotopes; D013890:Thiourea; D013997:Time Factors; D014316:Tritium; D014508:Urea; D001743:Urinary Bladder / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D014667:Vasopressins / Q000494:pharmacology*; D014867:Water
chemical_list: D002250:Carbon Radioisotopes; D007328:Insulin; D011868:Radioisotopes; D012975:Sodium Isotopes; D014867:Water; D014316:Tritium; D014667:Vasopressins; D003571:Cytochalasin B; D002713:Chlorine; D014508:Urea; D012964:Sodium; D000242:Cyclic AMP; D013890:Thiourea; D004121:Dimethyl Sulfoxide