The role of catecholaminergic neurons in the hypothalamus and medullary visceral zone in response to restraint water-immersion stress in rats

Key Laboratory of Animal Resistance of Shandong Province, College of Life Sciences, Shandong Normal University, Jinan 250014, Shandong, People's Republic of China.
The Journal of Physiological Sciences (Impact Factor: 1.9). 01/2011; 61(1):37-45. DOI: 10.1007/s12576-010-0119-6
Source: PubMed


The activity of catecholaminergic neurons in the hypothalamus and the medullary visceral zone (MVZ) in rats in response to restraint water-immersion stress (RWIS) was measured by use of dual Fos and tyrosine hydroxylase (TH) immunohistochemistry. In RWIS rats Fos immunoreactive (Fos-IR) nuclei dramatically increased in the paraventricular nucleus (PVN), the supraoptic nucleus (SON), the dorsal motor nucleus of the vagus (DMV), the nucleus of the solitary tract (NTS), the area postrema (AP), and the ventrolateral medulla (VLM). A small number of TH-immunoreactive (TH-IR) and Fos/TH double-labeling neurons in the PVN, and their absence from the SON, were observed in both RWIS and nonstressed rats. More TH-IR neurons were observed in the MVZ of RWIS rats than in nonstressed rats. In RWIS and nonstressed rats, the percentage of Fos-IR nuclei in TH-IR neurons was 38.0 and 14.3% in the DMV, 34.4 and 9.7% in the NTS, 18.6 and 4.5% in the AP, and 45.7 and 18.9% in the VLM, respectively. In conclusion, catecholaminergic neurons in the MVZ are involved in the response to RWIS; although the PVN and SON also participate in the response to RWIS, the mechanism is not via catecholaminergic neurons.

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    • "Ten rats were randomly divided into two groups in accordance with the duration of RWIS, respectively: the RWIS group and the control group. RWIS was performed as previously described [36]. Briefly, under light ether anesthesia, the four limbs of each rat in the stressed group were bounded gently but securely on a wooden board by use of medical adhesive tape. "
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