Calcium-independent inhibition of GABA(A) current by caffeine in hippocampal slices

Brain Research
M TaketoT Yoshioka

Abstract

Although inhibitory postsynaptic currents (IPSCs) mediated by GABA(A) receptor is thought to be affected by intracellular calcium ion concentration ([Ca2+]i), origin or route of [Ca2+]i increment has not been well elucidated. Reports on the effect of [Ca2+]i elevation on GABA(A)ergic IPSCs per se are also controversial. In this study, effects of caffeine and several other [Ca2+]i-mobilizing drugs were examined on the IPSCs in acute slices of rat hippocampus. Using the patch clamp recording method, spontaneous and evoked currents were recorded from CA3 neurons. Caffeine strongly inhibited both extra-synaptic and synaptic GABAergic IPSCs, regardless of the presence or absence of extracellular Ca2+. This inhibition was not relieved by the intracellular application of EGTA or 1,2-bis(2-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid (BAPTA). This inhibition by caffeine was not prevented by preequilibration with caffeine. Ca2+ store depletion caused by thapsigargin or repetitive stimulation by caffeine could not prevent the inhibition. Moreover, ruthenium red and ryanodine could not overcome the inhibition. On the contrary, GABA(A)ergic currents were not inhibited by stimulation with several Ca2+-mobilizing agonists. Forskolin could...Continue Reading

References

Feb 28, 1998·Pflügers Archiv : European journal of physiology·L G AguayoL S Satin
Oct 24, 2000·The Journal of Comparative Neurology·E Y ChenJ H Kordower
Mar 10, 2001·Neuroreport·T SugimotoS Okada
Oct 24, 2002·Trends in Neurosciences·Jean-Luc GaiarsaYehezkel Ben-Ari

❮ Previous
Next ❯

Citations

Sep 24, 2013·Neurochemistry International·Lisiane O PorciúnculaDenis B Rosemberg
Aug 5, 2010·Journal of Medicinal Chemistry·Tsuyoshi SakuradaRyuichi Sakai
Oct 29, 2013·Cellular and Molecular Life Sciences : CMLS·Julie A Mustard
Feb 10, 2006·Journal of Neurophysiology·Masako Isokawa, Bradley E Alger
Oct 18, 2005·The Journal of Pharmacology and Experimental Therapeutics·S L Cockerill, J S Mitcheson
Jul 1, 2017·Journal of Caffeine Research·Rachel L Poole, Michael G Tordoff
Nov 5, 2020·Neurochemistry International·Tina Hinton, Graham A R Johnston

❮ Previous
Next ❯

Related Concepts

Related Feeds

Basal Forebrain- Circuits

Basal forebrain is a region in the brain important for production of acetylcholine and is the major cholinergic output of the CNS. Discover the latest research on circuits in the basal forebrain here.