PMID: 8584427Jan 1, 1996Paper

A single non-L-, non-N-type Ca2+ channel in rat insulin-secreting RINm5F cells

Pflügers Archiv : European journal of physiology
V MagnelliE Carbone

Abstract

Single high-voltage-activated (HVA) Ca2+ channel activity was recorded in rat insulinoma RINm5F cells using cell-attached and outside-out configurations. Single-channel recordings revealed three distinct Ca2+ channel subtypes: one sensitive to dihydropyridines (DHPs)-(L-type), another sensitive to omega -conotoxin (CTx)-GVIA (N-type) and a third type insensitive to DHPs and omega -CTx-GVIA (non-L-, non-N-type). The L-type channel was recorded in most patches between -30 and +30 mV. The channel had pharmacological and biophysical features similar to the L-type channels described in other insulin-secreting cells (mean conductance 21 pS in control conditions and 24 pS in the presence of 5 microM Bay K 8644). The non-L-, non-N-type channel was recorded in cells chronically treated with omega -CTx-GVIA in the presence of nifedipine to avoid the contribution of N- and L-type channels. Channel activity was hardly detectable below -10 mV and was recruited by negative holding potentials (< -90 mV). The channel open probability increased steeply from -10 to + 40 mV. Different unitary current sublevels could be detected and the current voltage relationship was calculated from the higher amplitude level with a slope conductance of 21 pS. C...Continue Reading

References

Jun 17, 1992·European Journal of Pharmacology·E SherF Clementi
Jan 1, 1990·Pflügers Archiv : European journal of physiology·F M AshcroftP A Smith
Apr 1, 1990·Pflügers Archiv : European journal of physiology·E CarboneF Clementi
May 1, 1987·The Journal of Physiology·E Carbone, H D Lux
Apr 1, 1988·Pflügers Archiv : European journal of physiology·L S Satin, D L Cook
Oct 1, 1988·Pflügers Archiv : European journal of physiology·P RorsmanG Trube
Jan 1, 1989·Progress in Biophysics and Molecular Biology·F M Ashcroft, P Rorsman
Aug 1, 1981·Pflügers Archiv : European journal of physiology·O P HamillF J Sigworth
Apr 1, 1995·Pflügers Archiv : European journal of physiology·V MagnelliE Carbone
May 1, 1993·The Journal of General Physiology·P A SmithC M Fewtrell
Jan 1, 1994·European Biophysics Journal : EBJ·C MarchettiM Robello

❮ Previous
Next ❯

Related Concepts

Related Feeds

Adenoma, Islet Cell

Islet Cell Adenoma arises in the islet cells, which are insulin producing cells of the pancreas. These tumors can be either malignant or benign. Discover the latest research on Islet Cell Adenoma here.