Histamine H1 receptors in C6 glial cells are coupled to calcium-dependent potassium channels via release of calcium from internal stores.

摘要: We investigated the action of histamine on C6-astroglioma cells using patch clamp recording and intracellular calcium measurement. Application 100 µM hyperpolarized resting membrane potential increased free calcium. Membrane hyperpolarization was accompanied by a decrease in input resistance. The effect reversible responses persisted following repeated applications. In voltage experiments elicited an outward current associated with conductance increase reversal near Nernst for potassium. blocked mepyramine but not cimetidine or thioperamide suggesting that H1 receptor mediated response. Quinidine charybdotoxin, apamin, hyperpolarization. Buffering internal BAPTA diminished activation potassium channel, calcium-dependent K+-channel, which also found to be regulated protein kinase C phosphatases. dependent external sensitive pertussis toxin, cholera forskolin 8-bromo-cAMP. Both were thapsigargin phospholipase inhibitor U73122. These results indicate liberates from stores turn leads Ca2+ thereby channel C6 glial cells.