Differential expression of calbindin in nigral dopaminergic neurons in two mice strains with differential susceptibility to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine

Publication date: Available online 8 January 2016 Source:Journal of Chemical Neuroanatomy Author(s): D.J. Vidyadhara, H. Yarreiphang, P.L. Abhilash, T.R. Raju, Phalguni Anand Alladi Parkinson’s disease (PD) affects the A9 dopaminergic (DA) neurons of substantia nigra pars compacta (SNpc) whereas other DA neuronal subtypes are spared. The role of calbindin in this differential vulnerability has been long elicited, and is seen in the MPTP induced mice models of PD. A peculiar feature of mice models is the strain specific differences in the susceptibility to MPTP. Here, calbindin-D28K expression in DA neurons of SNpc of MPTP susceptible C57BL/6 mice and MPTP resistant CD-1 mice was studied as a susceptibility marker of degeneration. Unbiased stereological estimation of immunoperoxidase stained midbrain sections revealed significantly higher number of calbindin immunoreactive cells in SNpc of CD-1 mice compared to that of C57BL/6 strain. Western blotting showed minimal differences in the levels. Calbindin-tyrosine hydroxylase immunofluorescence co-labeling was performed to map the calbindin immunoreactive DA neurons in SNpc and ventral tegmental area (VTA) and to quantify the calbindin expression at cellular level. While the levels were comparable in VTA of both mice strains, the SNpc of CD-1 mice showed significantly higher calbindin expression. Within the SNpc, the medial and dorsal subdivisions showed higher calbindin expression in CD-1. The expression in the v...
Source: Journal of Chemical Neuroanatomy - Category: Neuroscience Source Type: research