EXPRESSION OF SHAKER-TYPE VOLTAGE-GATED POTASSIUM CHANNEL GENES IN THE GUINEA-PIG

Few potassium channel genes have been isolated in the guinea-pig despi te detailed electrophysiological characterization of potassium channel s in the guinea-pig heart. We obtained partial clones of Shaker-type p otassium channel genes in the guinea-pig and demonstrated their tissue distribution. Partial clones of the Shaker-type potassium channel gen es were obtained by RT-PCR or genomic PCR. mRNA expression was measure d by RNase protection assays in the heart, brain, and skeletal muscle. Three of the five obtained channel genes were expressed in the guinea -pig heart; Kv1.2, Kv1.3, and Kv1.6. Kv1.6 expression was markedly at a higher level in the atrium than in the ventricle. Expression of the channel genes in the guinea-pig was different from that in human and r at, which may contribute to the species-specific action potential wave form.