Norepinephrine and serotonin in central autonomic nuclei in the spontaneously hypertensive rat and two normotensive control rats.

Neurochemical analysis of norepinephrine and serotonin with high performance liquid chromatography with electrochemical detection (LCEC) in several microdissected central autonomic nuclei of 4 week old and 16 week old spontaneously hypertensive rats (SHR), normotensive Wistar-Kyoto rats (WKY), and control normotensive Wistar rats (WIS), revealed some differences among these strains, but only one change that correlated with the hypertensive state. Norepinephrine levels in the 4 week old SHR were greater in the parabrachial nuclei and the dorsal motor nucleus of X than in the WKY, but levels in the WIS normotensive also were greater than in the WKY, and equalled levels in the SHR. In the 16 week old rats, no difference was noted between NE levels in the SHR and WKY strains, but levels in the locus coeruleus and parabrachial nuclei of the WIS were greater than in both the SHR and WKY. Serotonin levels in the 4 week old SHR and WKY rats did not differ, while levels in the paraventricular nucleus, locus coeruleus, parabrachial nuclei, and medullary raphe nuclei of the WIS rat were greater than one or both of these inbred strains. In the dorsal motor nucleus of X in 16 week old rats, serotonin levels were greater in the SHR than in either the WKY or WIS controls, suggesting one possible transmitter action that should be explored further for its potential relationship to the hypertensive state.(ABSTRACT TRUNCATED AT 250 WORDS)