Immunohistochemical localization of C-RFamide, a FMRF-related peptide, in the brain of the goldfish, Carassius auratus

Carassius RFamide (C-RFa) is a novel peptide found in the brain of the Japa nese crucian carp. It has been demonstrated that mRNA of C-RFa is present i n the telencephalon, optic tectum, medulla oblongata, and proximal half of the eyeball in abundance. Immunohistochemical methods were employed to eluc idate the distribution of the peptide in the brain of the goldfish (Carassi us auratus) in detail. C-RFa-immunoreactive perikarya were observed in the olfactory bulb, the area ventralis telencephali pars dorsalis and lateralis , nucleus preopticus, nucleus preopticus preventricularis, nucleus laterali s tuberis pars posterioris, nucleus posterioris periventricularis, nucleus ventromedialis thalami, nucleus posterioris thalami, nucleus anterior tuber is, the oculomotor nucleus, nucleus reticularis superior and inferior, faci al robe, and vagal lobe. C-RFa immunoreactive fibers and nerve endings were present in the olfactory bulb, olfactory tract, area dorsalis telencephali pars centralis and medialis, area ventralis telencephali, midbrain tegment um, diencephalon, medulla oblongata and pituitary. However, in the optic te ctum the immunopositive perikarya and fibers were less abundant. Based on t hese results, some possible functions of C-RFa in the nervous system were d iscussed.