Catecholamine levels in the brain of SART (repeated cold)-stressed rats.

1 The catecholamine levels in the brains of SART (specific alternation of rhythm in temperature)-stressed (repeated cold-stressed) rats with vagotonic-type dysautonomia, were examined by high performance liquid chromatography with electrochemical detection techniques. 2 The cerebral cortex, hypothalamus and hippocampus of the SART-stressed rats had increased levels of noradrenaline. All brain areas examined showed increased levels of dopamine. 3 These increased catecholamine levels were still maintained by day 10 of SART stress. 4 Among brain areas examined, the hypothalamus showed most rapid change. 5 Cold-stressed rats showed increased noradrenaline levels only in the basal ganglia and dopamine levels in the hippocampus. 6 Rats suffering from restraint and water immersion stress showed decreased noradrenaline levels and increased dopamine levels. 7 These results suggest that SART-stressed animals are in a disease state differing from that of other so-called stressed animals, and changes in the hypothalamus give rise to the various symptoms in SART-stressed animals.