Immunocytochemical and radioautographic study of serotonin projections to cerebral ventricles of perinatal rats.
Anatomical relationships between serotoninergic (5-HT) fibers and cerebral ventricles were studied in rats from the 16th fetal day until the 9th postnatal day with immunocytochemistry and radioautography. In the last case, 5-HT neuronal elements were detected according to their specific uptake of intraventricularly injected [3H]5-HT. At the 16th fetal day, occasional 5-HT fibers first spread from the main place of their origin in the raphe nuclei to the dorsocaudal portion of the 3rd ventricle and aqueduct. Two days later, a more extensive network of 5-HT fibers appeared around the dorsal portion of the 3rd ventricle whereas fibers only rarely penetrated toward its ventral portion. By the 9th postnatal day, extensive networks of supraependymal fibers became noticeable in the lateral ventricles and in the dorsal portion of the 3rd ventricle. In addition, a number of 5-HT fibers surrounded the infundibular and preoptic recesses and sometimes penetrated to the ventricular cavity. The functional significance of hypothalamic and ventricular 5-HT as a modulator of either the growth and differentiation of the developing brain or of some specific neuroendocrine functions is discussed.
D000818:Animals; D000831:Animals, Newborn; D001345:Autoradiography; D001921:Brain / Q000196:embryology / Q000254:growth & development / Q000378:metabolism*; D002552:Cerebral Ventricles / Q000196:embryology / Q000254:growth & development / Q000378:metabolism*; D007124:Immunoenzyme Techniques; D009434:Neural Pathways / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism*
D012701:Serotonin