title: Catecholamine distribution and relationship to magnocellular neurons in the paraventricular nucleus of the rat.
abstract: The distribution of catecholamine synthesizing enzymes within the paraventricular nucleus of the rat hypothalamus is elucidated immunocytochemically by use of antibodies to tyrosine hydroxylase, dopamine beta-hydroxylase, and phenylethanolamine-N-methyltransferase. Tyrosine hydroxylase-immunostained cell bodies are localized in the periventricular stratum and adjacent parvocellular regions, but rarely in magnocellular subnuclei of the paraventricular nucleus. Tyrosine hydroxylase-immunostained fibers are present in greatest density in the periventricular zone, and moderate density in the parvocellular and magnocellular subnuclei. Dopamine beta-hydroxylase-immunostained fibers are remarkably dense in the posterior magnocellular division of the paraventricular nucleus, especially in the dorso-lateral portion where vasopressin-containing cells predominate. Noradrenergic fiber input to these magnocellular neurons is likely since phenylethanolamine-N-methyltransferase-immunostained fibers are sparse in magnocellular subnuclei of the paraventricular nucleus. Dual immunocytochemical staining of thick and thin tissue sections demonstrates with clarity an anatomical association of dopamine beta-hydroxylase-immunostained fibers and magnocellular neurons. Dopamine beta-hydroxylase-immunostained and phenylethanolamine-N-methyltransferase-immunostained fibers are dense in the medial parvocellular component of the paraventricular nucleus; distinct features of both antisera are presented.
mesh_terms: D000818:Animals; D002395:Catecholamines / Q000096:biosynthesis*; D004299:Dopamine beta-Hydroxylase / Q000378:metabolism*; D006651:Histocytochemistry; D007124:Immunoenzyme Techniques; D008297:Male; D009474:Neurons / Q000166:cytology / Q000201:enzymology*; D010286:Paraventricular Hypothalamic Nucleus / Q000166:cytology / Q000201:enzymology*; D010625:Phenylethanolamine N-Methyltransferase / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D014018:Tissue Distribution
chemical_list: D002395:Catecholamines; D004299:Dopamine beta-Hydroxylase; D010625:Phenylethanolamine N-Methyltransferase