Progressive training effects on neuronal hypothalamic activation in the rat

The purpose of this study was to examine whether progressive training exercise resulted in changes in neuronal expression of c-Fos in the hypothalamic regions (paraventricular nucleus, supraoptic nucleus and suprachiasmatic nucleus) and subfornical organ of Wistar rats and its relation to hydromineral parameters such as plasma proteins, osmolality and hematocrit. Rats were trained progressively in a running wheel over four days, while control rats were not provided with the opportunity to exercise. c-Fos cellular activity was immunohistochemically stained in accordance with the ABC method. The number of c-Fos immunoreactive cells was counted using standard imaging software. c-Fos in the PVN and SO nuclei was found to be significantly increased in trained rats 1 h post-exercise compared with control and 24 h post-exercise groups. However, no significant differences were found between trained and control rats in the SQ and SFO. These findings provide useful information of interest for future studies on brain specific regions involved in hydromineral balance in response to progressive exercise. (C) 2012 Elsevier Ireland Ltd. All rights reserved.