Skip to Main content Skip to Navigation
Journal articles

Neuroprotection of midbrain dopamine neurons by nicotine is gated by cytoplasmic Ca 2+

Abstract : Epidemiological and experimental evidence indicates that nicotine is protective for Parkinson disease vulnerable dopamine neurons, but the underlying mechanism of this effect remains only partly characterized. To address this question, we established rat midbrain cultures maintained in experimental conditions that favor the selective and spontaneous loss of dopamine neurons. We report here that nicotine afforded neuroprotection to dopamine neurons (EC(50)=0.32 μM) but only in a situation where cytosolic Ca(2+) (Ca(2+)(cyt)) was slightly and chronically elevated above control levels by concurrent depolarizing treatments. By a pharmacological approach, we demonstrated that the rise in Ca(2+)(cyt) was necessary to sensitize dopamine neurons to the action of nicotine through a mechanism involving α-bungarotoxin-sensitive (presumably α7) nicotinic acetylcholine receptors (nAChRs) and secondarily T-type voltage-gated calcium channels. Confirming the role played by α7 nAChRs in this effect, nicotine had no protective action in midbrain cultures prepared from genetically engineered mice lacking this receptor subtype. Signaling studies revealed that Ca(2+)(cyt) elevations evoked by nicotine and concomitant depolarizing treatments served to activate a survival pathway involving the calcium effector protein calmodulin and phosphatidylinositol 3-kinase. Collectively, our data support the idea that the protective action of nicotine for dopamine neurons is activity-dependent and gated by Ca(2+)(cyt).
Document type :
Journal articles
Complete list of metadatas

Cited literature [39 references]  Display  Hide  Download

https://hal-pasteur.archives-ouvertes.fr/pasteur-02936389
Contributor : Rhizlane Laatabi <>
Submitted on : Friday, September 11, 2020 - 11:29:59 AM
Last modification on : Wednesday, September 30, 2020 - 3:09:06 AM

Identifiers

Citation

Damien Toulorge, Serge Guerreiro, Audrey Hild, Uwe Maskos, Etienne Hirsch, et al.. Neuroprotection of midbrain dopamine neurons by nicotine is gated by cytoplasmic Ca 2+. FASEB Journal, Federation of American Society of Experimental Biology, 2011, 25 (8), pp.2563-2573. ⟨10.1096/fj.11-182824⟩. ⟨pasteur-02936389⟩

Share

Metrics

Record views

19