Elsevier

Neuroscience Letters

Volume 255, Issue 1, 9 October 1998, Pages 33-36
Neuroscience Letters

Cholinergic agonists increase intracellular Ca2+ in cultured human microglia

https://doi.org/10.1016/S0304-3940(98)00706-XGet rights and content

Abstract

Microglia are resident phagocytic cells in the central nervous system (CNS), and can be activated in response to various stimuli including neurotransmitters. Using fura-2 imaging, we investigated the effects of carbachol (CCh), a cholinergic agonist, on [Ca2+]i in cultured human microglia. Treatment of microglia with CCh (100 μM) produced a transient increase in [Ca2+]i, which was atropine-sensitive and was associated with release from intracellular Ca2+ stores. Successive applications of CCh showed a change in the amplitude of the [Ca2+]i signal consistent with desensitization. These results show that human microglia express functional muscarinic receptors and respond to cholinergic agonists. The rapid change of [Ca2+]i in microglia may serve as a second messenger to trigger downstream cascades which contribute to signalling pathways in CNS pathology.

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Acknowledgements

This work was supported by grants from the British Columbia Health Research Foundation (to C.K.), the Natural Science and Engineering Research Council of Canada (to J.G.M.), and the MS Society of Canada (to S.U.K).

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