Potassium Channels in Adrenocortical and Parathyroid Cells
In the last decade numerous studies on the electrophysiology of endocrine cells have firmly established the important role played by membrane electrical events in “stimulus-release coupling”16. However, very recent development of patch clamp techniques8 has made it possible to undertake a detailed characterization of membrane ionic conductances present in these cells, and to elucidate their precise role in the regulation of secretion. Among the different ionic channels so far identified in endocrine cells, are several types of K-channels that are important not only for the regulation of action potential duration, and thus the amount of Ca entry, but also because some of these channels are the target for the action of secretagogues and intracellular messengers. Different K- channels have been identified in β-cells (see this workshop) as well as in chromaffin13,25 pituitary and adrenocortical cells21.
KeywordsEndocrine Cell Membrane Patch Adrenocortical Cell Parathyroid Cell Parathyroid Hormone Secretion
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