Capsaicin blocks Ca2+ channels in isolated rat trigeminal and hippocampal neurones.
Effects of capsaicin, an essential ingredient of hot peppers, on high voltage-activated (HVA) calcium channels were investigated in voltage-clamped and internally perfused acutely dissociated rat trigeminal and hippocampal neurones. In micromolar concentrations capsaicin inhibited the whole HVA Ca2+ current without affecting resting membrane conductance in both types of neurones. IC50 values of 14.5 microM and 21.2 microM (n = 5) were obtained in sensory and hippocampal neurones, respectively. Capsaicin-induced inhibition became irreversible after prolonged incubation (30 s) with the drug. It is concluded that capsaicin is a nonspecific blocker of HVA Ca2+ channels in different types of nerve cells.
Kopanitsa
M V
MV
Department of Cellular Membranology, Bogomoletz Institute of Physiology, Ukraine.
Panchenko
V A
VA
Magura
E I
EI
Lishko
P V
PV
Krishtal
O A
OA
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D015220:Calcium Channels / Q000187:drug effects* / Q000378:metabolism; D002211:Capsaicin / Q000494:pharmacology*; D004594:Electrophysiology; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D066298:In Vitro Techniques; D015640:Ion Channel Gating / Q000187:drug effects; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D018408:Patch-Clamp Techniques; D017966:Pyramidal Cells / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014278:Trigeminal Nuclei / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism
D002121:Calcium Channel Blockers; D015220:Calcium Channels; D002211:Capsaicin; D002118:Calcium