Figure 2.

Dopamine (TH-immunoreactive) but not serotonin (5-HT-immunoreactive) neurons in the vPAG are depleted by 6-hydroxydopamine. Dual staining of the same tissue section for TH-ir (A) and 5-HT-ir (B) neurons in the DRN indicates that they are entirely separate populations (inset in A shows higher magnification in merged image). An asterisk (*) marks the identical location in A and in the inset. After 6-hydroxydopamine lesions, few TH-ir cells remained (C), but serotoninergic neurons were not affected (D). Scale bar: (in C) A, B, 100μm; C, D, 250 μm.