DISTRIBUTION OF SUBSTANCE P-LIKE AND LEUCINE-E NKEPHALIN-LIKE IMMUNORE-ACTIVE NEURONS IN THE MIDBRAIN RAPHE NUCLEI OF THE RAT / 解剖学报

ABSTRACT

The different distributions of substance P(SP)-and leucine-enkephalin (L-ENK)-like immunoreactive neurons in the midbrain raphe nuclei of the rats have been studied, using PAP immunocytochemical technique. The results showed four main points: 1. SP-containing immunoreactive cell bodies were only seen in the most caudal part of the dorsal raphe nucleus, the average number of SP-positive cell bodies was about 167 in each animal. The L-ENK-like immunoreactive positive cell bodies were found almost in the whole length of the dorsal raphe nucleus, the L-ENK-positive cell bodies were about 132 in each animal. 2. L-ENK-Iike immunoreactive perikarya were mainly located in the midline area of the dorsal raphe nucleus. Besides the above areas, SP-containing immunoreactive cell bodies were also located bilaterally in the extended area from the raphe. 3. L-ENK-containing immunoreactive cell bodies constantly appeared in the median raphe nuclei, the average number was about 199 in each animal, but SP-containing immunoreactive bodies were only observed in this nucleus of two rats. 4. Some SP-like immunoreactive cell bodies or processes were observed in the vincinty of vascular walls, but the L-ENK positive neurons were not found similar results. The present experiment showed that the SP-like immunoreactive perikarya is located in the median raphe nuclei of the rat.