Electrophysiological Study of Potassium Channel in Parotid Gland Acinar Cell

Abstract

When the salicary gland acinar cells are stimulated vy secretafofesm its intracellular Ca^(2+) lons are increased and potassium channels are opened. the purpose of this experiment is to study the characteristics of potassium channel and its channel activity induced by Phenylephrine using dissociated aclnar cells from the parotid gland. the parotid and its channelactivity induced by Phenylephrine using dissociated aclnar cells from the parotid gland. The parotid gland acinar cells were collected from Sprague-Dawley rat by trypsln and collafenase treatment. Isolated acinar cells were placed in 100% oxygenated tyrode solution. To record channel activities, mocropipette filled with HEPES-buffered high potassium solution with 1-5 ㏁ resistance were used. Membrane currents were recorded by cell-attached patch clamp method. the channel activities were recorded and analyzed on pCiamp soft ware. Two distinct types of potassium channels in parotid gland acinar cells were observed. The one type which had large conductance about 170pS was voltage dependent. The other type which had small conductance was uoltage independent. The potassium current was activated by phenylephrine (1×10^(-4) M) which is an α-adrenergic agonist at 60 mV holding potential (Vp) by increasing open probability.