Environmental events that modify the catecholamine fluorescence of the A2 cell bodies in nucleus tractus solitarii.

Found that the fluorescence intensity of the catecholamine cell bodies of the A2 group--as determined by microfluorimetry--increased significantly due to exposure of male rats of the Sprague-Dawley-Ivanovas strain to the following environmental events: placement from the colony cage into a cold (4°C) room for a period of 10 min, isolation from the colony for 6-7 days, and satiation of grouped Ss by allowing access to sweetened milk for 15 min. The following events failed to affect the intensity of the cells of A2: reduction of the group colony size from 8 to 3 rats per colony for 6-7 days and presentation of water instead of milk after the rats had experienced 6-7 days of milk satiation. Results indicate that aversive as well as rewarding environmental events activate the catecholamine cells of A2. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)