Serotoninergic endings on VIP-neurons in the suprachiasmatic nucleus and on ACTH-neurons in the arcuate nucleus of the rat hypothalamus. A combination of high resolution autoradiography and electron microscopic immunocytochemistry.
A combination of immunocytochemistry with transmitter specific autoradiography at the electron microscopic level was used to identify vasoactive intestinal polypeptide (VIP)- or ACTH-containing neurons and serotoninergic nerve terminals in the suprachiasmatic (SCN) and arcuate nuclei (AN). We observed nerve terminals showing selective uptake of [3H]serotonin forming synaptic contact with perikarya or dendrites where the postsynaptic structures exhibited VIP-like immunoreactivity in the SCN and ACTH-like immunoreactivity in the AN. The findings provide ultrastructural evidence that serotoninergic nerve fibers terminate on VIP-neurons in the SCN and on ACTH-neurons in the AN.
D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000378:metabolism*; D001345:Autoradiography; D007124:Immunoenzyme Techniques; D008297:Male; D008854:Microscopy, Electron; D009474:Neurons / Q000378:metabolism; D051381:Rats; D012701:Serotonin / Q000378:metabolism*; D013493:Suprachiasmatic Nucleus / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism*
D012701:Serotonin; D014660:Vasoactive Intestinal Peptide; D000324:Adrenocorticotropic Hormone