Immunohistochemical localization of calcitonin gene-related peptide in the brain of the rainbow trout; Salmo gairdneri

105 25 IMMUNOHISTOCHEMICAL LOCALIZATION OF CALCITONIN GENE-RELATED PEPTIDE IN THE BRAIN OF THE FROG; Rana temporaria C. WOLFBAUER and G. SKOFITSCH, Department of Zoology, Karl-Franzens-Univ. A-8010 GRAZ Using the method of indirect immunocytochemistry and a polyclonal rabbit anti hCGRP serum we were able to demonstrate CGRP-like immunoreactive (IR) bodies and nerve fibers in the frogs central nervous system. CGRP-IR cell bodies were observed in the telencephalic nucleus of the diagonal band, the diencephalic preoptic and dorsal infundibular nuclei as well as in the posterior thalamic nuclei and the mesencephalic anteroventral and profundus nuclei. Moderate to dense accumulations of nerve fibers and endings were observed in the teiencephalic diagonal tract, the arnygdala, the accumbens nucleus and the ventral striatum. In the Diencephalon moderate CGRP-IR fiber densities were observed in the ventrolateral and ventromedial thalamus,the posterocentral thalamic nucleus, the anterior dorsolateral and dorsomedial nuclei, the ventral infundibular nucleus, and the nucleus rotundus; high fiber densities were noted in the preoptic and dorsal infundibular nuclei. In the mesencephalon moderate fiber densities were noted in the anteroventral, profundus, reticularis isthmi and the film nuclei. The medulla oblongata showed moderate to dense fiber distributions in the dorsal spinocerebellar tract, and the descending tracts of the spinal trigeminal and acustic nerves.The regional distribution of CGRP-IR in the frogs CNS strongly resembles that of the mammalian CNS with the exception of the neopallium and the motornuctei of the medulla oblongata and spinalis which were devoid of CGRP-IR cell bodies. This work was supported by the Austrian Scientifc Research Funds grant numbers P6086M and P7050M

26 IMMUNOHISTOCHEMICAL LOCALIZATION OF CALCITONIN GENE-RELATED PEPTIDE IN THE BRAIN OF THE RAINBOW TROUT; Salmo gairdneri A. WURZINGER and G. SKOFITSCH, Department of Zoology, Karl-Franzens-Univ. A-8010 GRAZ Using the method of indirect immunocytochemistry and a polyclonal rabbit anti hCGRP serum we were able to demonstrate CGRP-Iike immunoreactive (IR) bodies and nerve fibers in the central nervous system of the rainbow trout. CGRP-IR cell bodies were mostly restricted to medullary and spinal motornuclei e.g., the ventral horn cells of the spinal cord, the oculomotor nucleus and the ambiguus nucleus of the medulla. In the trigeminal and acustieolateral area the CGRP-IR ceils could be sensory. No CGRP-IR cells were seen in higher central areas. A very intense innervation of the CNS with CGRP-IR nerve fibers was seen in the area of the lateral recess from its most rostral extension where the ventricle separates to the most caudal end at the inferior lobes. Another area of dense CGRP-IR innervation is the dorsomedial nucleus of the medulla. Dense innervation was observed in the dorsomedial and ventromedial thalamic nuclei, and the dorsomedial telencephalic area. Areas of moderate innervation with CGRP-IR nerves are the medial telencephalic areas, most hypothalamic nuclei, the superficial strata of the tectum, the pretectum, the mesencephalic and medullary reticular formation. Similar to higher vertebrates we find CGRP-IR cell bodies in motor areas of the hindbrain and spinal cord. As a consequence of the missing innervation of the fish pituitary with CGRP we did not see CGRP-IR cell bodies in the hypothalamus which was also seen in the doves brain, in contrast, frog, lizard and rat showed hypothalamic CGRP-IR cells and a suggestive innervation of the pituitary. This work was supported by the Austrian Scientifc Research Funds grant numbers P6086M and PTO50M