Co-localization of neurotensin- and cholecystokinin-like immunoreactivities in catecholamine neurons in the rat dorsomedial medulla.
Co-localization of neurotensin and cholecystokinin in tyrosine hydroxylase-containing neurons in the nucleus tractus solitarius of the rat was demonstrated by immunocytochemistry with fluorescent double-staining combined with the peroxidase-antiperoxidase method. Co-localization of neurotensin/tyrosine hydroxylase or cholecystokinin/tyrosine hydroxylase was consistently found in small neurons in the region dorsomedial to the tractus solitarius at the level of the area postrema with high percentages of co-existence: 91.0% tyrosine hydroxylase-immunoreactive neurons contained neurotensin and 91.1% cholecystokinin, suggesting that they represent the same neurons. Accordingly, co-localization of neurotensin and cholecystokinin was assessed on tyrosine hydroxylase-containing neurons bisected into two adjacent sections, and then identified in a certain number of the catecholamine neurons in this region. Furthermore these catecholamine neurons exhibited immunoreactivity for an adrenaline-synthesizing enzyme, phenylethanolamine N-methyltransferase. It was concluded that catecholamine, in particular adrenaline, neurons, characterized by co-localization of neurotensin and cholecystokinin, established a distinct subpopulation in the catecholaminergic system in the dorsomedial medulla of the rat.
D000818:Animals; D002395:Catecholamines / Q000032:analysis*; D002766:Cholecystokinin / Q000032:analysis*; D005455:Fluorescent Antibody Technique; D008526:Medulla Oblongata / Q000032:analysis* / Q000166:cytology / Q000201:enzymology; D009474:Neurons / Q000032:analysis* / Q000201:enzymology; D009496:Neurotensin / Q000032:analysis*; D010625:Phenylethanolamine N-Methyltransferase / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis
D002395:Catecholamines; D009496:Neurotensin; D002766:Cholecystokinin; D014446:Tyrosine 3-Monooxygenase; D010625:Phenylethanolamine N-Methyltransferase