Dissociation of membrane potential and hormone secretion in bovine parathyroid cells

J. J. Morrissey, S. Klahr

Research output: Contribution to journalArticle

7 Scopus citations

Abstract

An increase in the calcium ion concentration of the medium from 0.5 to 2.0 mM is associated with a 65% decrease in the secretion of parathyroid hormone from dispersed parathyroid cells. This maneuver also depolarized the cell membrane from -55 to -21 mV as measured by the distribution of [3H]tetraphenylphosphonium ion between cells and medium. An increase in the potassium ion concentration of the medium to 50 mM caused a 67% increase in hormone secretion at 0.5 mM calcium and depolarized the cell to -31 mV. The high potassium did not significantly change hormone secretion or the membrane potential at 2.0 mM calcium. Chlorpromazine inhibited hormone secretion by 40% and depolarized the cell to -30 mV at 0.5 mM calcium in the medium. Chlorpromazine did not change hormone secretion or membrane potential in cells incubated at 2.0 mM calcium. These results suggest that depolarization of the cell by calcium cannot account by itself for the inhibition of hormone secretion and chlorpromazine mimics the effect of an increase in calcium on parathyroid cell function.

Original languageEnglish
Pages (from-to)E102-E105
JournalAmerican Journal of Physiology - Endocrinology and Metabolism
Volume8
Issue number1
DOIs
StatePublished - Jan 1 1983

Fingerprint Dive into the research topics of 'Dissociation of membrane potential and hormone secretion in bovine parathyroid cells'. Together they form a unique fingerprint.

  • Cite this