title: Evidence for two distinct voltage-gated calcium channel currents in bovine adrenal glomerulosa cells.
abstract: We analyzed inward Ca2+ currents in single bovine adrenal glomerulosa cell using whole-cell patch clamp techniques. Two types of voltage-gated Ca2+ channel currents were identified. One was a transient (T) type which decayed within 100 ms, characterized by a low threshold voltage (about -70 mv) similar to that seen in rat adrenal glomerulosa cells (Matsunaga, H. et al. (1987) Pflügers Arch. 408, 351-355.) Another was a long-lasting (L) type which shows a more positive threshold potential. The present results suggest that while T type Ca2+ channels may explain initial calcium influx in response to an elevation in extracellular K+, L type Ca2+ channels may allow sustained calcium influx which is necessary for sustained aldosterone secretion.
mesh_terms: D000302:Adrenal Cortex / Q000032:analysis* / Q000166:cytology; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002417:Cattle; D007473:Ion Channels / Q000145:classification* / Q000187:drug effects / Q000378:metabolism; D008564:Membrane Potentials; D011188:Potassium / Q000494:pharmacology
chemical_list: D007473:Ion Channels; D011188:Potassium; D002118:Calcium