Figure 4

Chronic behavioral stress exaggerates the MPTP-dependent cell loss in the substantia nigra. (a) Representative images of immunohistochemistry analyses for TH reactivity in the substantia nigra of C57BL/6 mice receiving vehicle alone (CTR, n=10); MPTP (n=12); MPTP+RI (n=9); or RI (n=9; scale bars, 100 μm (× 10); 100 μm (× 40)). (b) Quantitative analysis of the TH immunoreactivity shown in a (*P<0.05). Results are mean±s.e.m. MPTP, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine; RI, restraint/isolation; TH, tyrosine hydroxylase.