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Updated: Aug 19, 2026

Whole-Cell Recording of Calcium Release-Activated Calcium (CRAC) Currents in Human T Lymphocytes
Published on: December 21, 2010
L- and T-type voltage-gated Ca2+ channels in human granulosa cells: functional characterization and cholinergic
Daniela Platano1, M Cristina Magli, Anna Pia Ferraretti
1Department of Human and General Physiology, University of Bologna, Via S. Donato 19/2, I-40127 Bologna, Italy.
Abstract:
Using the whole-cell configuration of the patch-clamp technique, we have characterized two types of ionic currents through voltage-dependent Ca2+ channels in human granulosa cells. One is long-lasting, activates at approximately -20 mV, reaches the peak at approximately +20 mV, has an inactivation time constant of 132.5 +/- 5.6 msec at 20 mV, and is sensitive to dihydropyridines. The other is transient, activates at approximately -40 mV, peaks at approximately -10 mV, has an inactivation time constant of 38.8 +/- 1.8 msec at -10 mV, displays a voltage-dependent inactivation, and is sensitive to 100 microm Ni2+, but not to dihydropyridines. Biophysical and pharmacological properties of these currents indicate that they are gated through L- and T-type calcium channels, respectively. The cholinergic receptor agonist carbachol (50 microm) reduces the amplitude of the currents through both L-type (-34.7 +/- 6.4%; n = 10) and T-type (-52.6 +/- 7.4%; n = 8) channels, suggesting a possible role of these channels in the cholinergic regulation of human ovarian functions.
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