Oropharyngeal receptors and Fos staining following dehydration and rehydration in the rat

• Published in: The FASEB journal 2007-04, Vol.21 (5), p.A515-A515
• Main Authors: Cunningham, J. Thomas, Martinez, Michelle A., Little, Joel T., Gottlieb, Helmut B., Ji, Lisa L.
• Format: Article
• Language: English
• ISSN: 0892-6638; 1530-6860
• DOI: 10.1096/fasebj.21.5.A515-a

Immunohistochemistry for Fos was used to determine the role of the superior laryngeal nerve in conscious rats following water deprivation and rehydration. Adult male rats were subjected to either unilateral superior laryngeal nerve section (SLNX) or sham surgery. Two weeks later rats from each surgical group were water deprived for 48 h (DH) or water deprived for 46 h hours and given access to water for 2 h prior to perfusion (RH). Controls (CON) were allowed ad libitum access to water. Brains were processed for Fos using a commercially available antibody. Changes in plasma osmolality and hematocrit following DH and RH were not significantly different between SLNX and sham. Water intake in RH rats was not significantly affected by SLNX. In the nucleus of the solitary tract (NTS) of sham rats, both DH and RH produced significant increases in Fos staining bilaterally compared to CON. In SLNX rats, DH significantly increased Fos in both ipsilateral and contralateral NTS that was not different from sham rats. SLNX significantly decreased Fos staining in the ipsilateral NTS of RH rats compared to sham RH rats. Fos staining was not affected in the contralateral NTS of SLNX RH rats. In the supraoptic nucleus (SON) of sham rats, DH significantly increased Fos staining while RH prevented this increase. DH significantly increased Fos staining in the SON of SLNX rats. Following RH in SLNX rats, Fos staining in the ipsilateral SON was significantly greater than the contralateral SON and significantly lower than DH. This suggests that the SLN contributes to Fos staining in the NTS and SON following RH but not DH. (HL062579, DK57822)