Present address: Department of Public Health and Community Medicine, at Westmead Hospital, Westmead 2145, and Sydney University, Sydney 2006, NSW, Australia.
Cortical and nigral deafferentation and striatal cholinergic markers in the rat dorsal striatum: different effects on the expression of mRNAs encoding choline acetyltransferase and muscarinic m1 and m4 receptors
Version of Record online: 26 AUG 2008
© European Neuroscience Association
European Journal of Neuroscience
Volume 11, Issue 10, pages 3659–3668, October 1999
How to Cite
Kayadjanian, N., Schofield, W. N., Andren, J., Sirinathsinghji, D. J. S. and Besson, M. .-J. (1999), Cortical and nigral deafferentation and striatal cholinergic markers in the rat dorsal striatum: different effects on the expression of mRNAs encoding choline acetyltransferase and muscarinic m1 and m4 receptors. European Journal of Neuroscience, 11: 3659–3668. doi: 10.1046/j.1460-9568.1999.00788.x
- Issue online: 26 AUG 2008
- Version of Record online: 26 AUG 2008
- Received 20 July 1998, revised 27 May 1999, accepted 14 June 1999
- Cited By
- bilateral sensorimotor cortex ablation;
- in situ hybridization;
- unilateral 6-hydroxydopamine
The regulation of the striatal m1 and m4 muscarinic receptor mRNA as well as the choline acetyltransferase (ChAT) mRNA expression by nigral dopaminergic and cortical glutamatergic afferent fibres was investigated using quantitative in situ hybridization histochemistry. The effects induced by a unilateral lesion of the medial forebrain bundle and a bilateral lesion of the sensorimotor (SM) cortex were analysed in the dorsal striatum 3 weeks after the lesions. Dopaminergic denervation of the striatum resulted in a marked decrease in the levels of m4 mRNA throughout the striatum, while the levels of muscarinic m1 mRNA and ChAT mRNA in cholinergic neurons were unaffected by the lesion. In contrast, following bilateral cortical ablation, the levels of the muscarinic m1 mRNA were significantly increased in the striatal projection area of the SM cortex, whereas the expression of m4 mRNA remained unchanged. Single cholinergic cell analysis by computer-assisted grain counting revealed a decreased labelling for ChAT mRNA per neuron following cortical ablation. However, in contrast to the topographical m1 mRNA changes, the decreased ChAT mRNA expression was evenly distributed within the striatum, suggesting an indirect cortical control upon striatal cholinergic interneurons. Altogether, these data suggest that dopaminergic nigral and glutamatergic cortical afferents modulate differentially cholinergic markers, at the pre- and post-synaptic levels. Beside the fact that nigral and cortical inputs exert an opposite control on cholinergic neurotransmission, our study further shows that this control involved different muscarinic receptor subtypes: the m4 and m1 receptors, respectively.