Pharmacologic blockade of ionic channels in lens membranes.
Channel blockers are compounds that disrupt the flow of current through ionic channels in membranes. We use the patch clamp technique to characterize the interactions of blocking particles with individual lens membrane channels. The mean current amplitude at many voltages is determined. The ratios of blocked to unblocked currents at several blocker concentrations are compared to a one binding site model to determine the kd and electrical distance of the site. When channel flickers are too fast to be resolved, the calculation of the power spectral density of the open channel current is useful. It is suggested that channel blockers might be useful therapeutically in some types of cataracts.
Rae
J L
JL
Department of Physiology, Mayo Foundation, Rochester, Minn.
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D003650:Decamethonium Compounds / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004594:Electrophysiology; D006801:Humans; D007473:Ion Channels / Q000187:drug effects*; D007908:Lens, Crystalline / Q000378:metabolism*; D008566:Membranes / Q000378:metabolism; D008962:Models, Theoretical; D015221:Potassium Channels / Q000502:physiology
D003650:Decamethonium Compounds; D007473:Ion Channels; D015221:Potassium Channels; C033019:decamethonium; D002118:Calcium