Heavy Metals and Membrane Functions of an Alveolar Epithelium

摘要: The anuran lung can be mounted as a planar sheet for assessment of bioelectric properties and solute water permeation. the bullfrog exhibited transmural electrical p.d. 19 mV (pleura positive), resistance 700 ohm cm2 short-circuit current (Isc) 27 μa/cm2. Isc reflected active Cl- secretion into lumen by transport mechanism located at luminal border alveolar epithelial cell layer. Other halides SCN- were secreted; other bathing solution ions H2O followed predictions passive diffusion. Exposure surface or disaggregated cells to heavy metals revealed two patterns response. HgCl2 decreased Isc, ciliary motility QO2; CdCl2 NiCl2 inhibited only QO2 cilia. Effects reversed dimercaprol but not albumin. SH agents limited did reverse toxicity. None altered osmotic flow across even though most increased urinary bladder from same species. effects on changes in ion compound stimulated pleural flux selectively. Without complexer, transient stimulation was decrease an indiscriminate increase permeability. We conclude that responses separate functions ciliated non-ciliated epithelium. Furthermore, non-specific damage selective action pump.