substance p-like immunoreactive cell bodies were found in the hypothalamus , in a periventricular cell group in the rostral mesencephalon , in the interpeduncular nucleus , in and ventral to the descending nucleus of the trigeminal nerve , in and directly ventral to the nucleus of the solitary tract , scattered in the brain stem reticular formation and in the trigeminal and spinal ganglia .
C0025462
mesencephalon
C0006121
brain stem