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. 1990 Aug;58(2):567–571. doi: 10.1016/S0006-3495(90)82400-0

Single-channel recordings of two types of calcium channels in rat pancreatic beta-cells.

S Sala 1, D R Matteson 1
PMCID: PMC1280995  PMID: 2169918

Abstract

Using the cell-attached configuration of the patch clamp technique, we have identified two different types of Ca channels in rat pancreatic beta-cell membranes. The two channels differ in single channel conductance, voltage dependence, and inactivation properties. The single-channel conductance, measured with 100 mM Ba2+ in the pipette, was 21.8 pS for the large channel and 6.4 pS for the small channel. The large-conductance channel is similar to the fast deactivating or L-type Ca channel described in other preparations. It is voltage dependent, has a threshold for activation around -30 mV, and can be activated from a holding potential of -40 mV. On the other hand, the small-conductance Ca channel is similar to the SD or T type Ca channel; it has a lower activation threshold, around -50 mV, and it can be inactivated by holding the membrane potential at -40 mV.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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