Calcium efflux and cycling across the synaptosomal plasma membrane
Year: 1985
Type: article
Abstract: Ca2+ efflux from intact synaptosomes is investigated. Net efflux can be induced by returning synaptosomes from media with elevated Ca2+ or high pH to a normal medium. Net Ca2+ efflux is accelerated when the Na+ electrochemical potential gradient is collapsed by veratridine plus ouabain. Under steady-state conditions at 30 degrees C, Ca2+ cycles across the plasma membrane at 0.38 nmol . min-1 . mg-1 of protein. Exchange is increased by 145% by veratridine plus ouabain, both influx and efflux being increased. Increased influx is probably due to activation of voltage-dependent Ca2+ channels, since it is abolished by verapamil. The results indicate that, at least under conditions of low Na+ electrochemical gradient, some pathway other than a Na+/Ca2+ exchange must operate in the plasma membrane to expel Ca2+.
Source: Biochemical Journal
DOI: 10.1042/bj2260225
Authors: R Snelling, D Nicholls
Institution: University of Dundee
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2224969106