title: A quantitative, immunochemical demonstration of the postnatal development of neurotensin in the medial preoptic area of the rat.
abstract: The postnatal ontogeny of neurotensin (NT) in the medial preoptic area (MPO) of the rat was quantitatively investigated using immunocytochemical and neurochemical techniques. On postpartum day 0, NT-like immunoreactive neurons could not be identified within the MPO by peroxidase-antiperoxidase histochemistry and, in fact, did not appear until 9 days postpartum. After this age, the number of NT cells in the MPO increased ontogenetically, as did concentrations of NT in MPO extracts measured by radioimmunoassay and enzyme-linked immunosorbent assay. In organotypic MPO explants derived from neonatal rats, NT-like immunoreactivity was detected only after the explants were maintained 14 days in vitro, after which, the number of NT-like immunoreactive somata increased as the time in vitro was extended. These findings indicate that a substantial amount of differentiation occurs postnatally in the MPO both in vivo and in vitro and, more specifically, that the ontogenetic expression of NT may be an intrinsic property of the MPO.
mesh_terms: D000367:Age Factors; D000818:Animals; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D007124:Immunoenzyme Techniques; D008297:Male; D009496:Neurotensin / Q000032:analysis* / Q000378:metabolism; D011301:Preoptic Area / Q000032:analysis* / Q000254:growth & development / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D009496:Neurotensin