Genetic study of norepinephrine in brains of mice selected for differences in blood pressure.

Norepinephrine concentration of the whole brain was found to be statistically different between the HBP and LBP mouse stains that had been selectively bred for high and low systolic blood pressure, respectively. Crosses between these strains resulted in statistically different NE levels between the reciprocal F1 males and the genetical analysis revealed a significant sex-linked factor or factors. Dissection of the brain into eight regions and subsequent biochemical analyses revealed statistically higher NE content in the LBP compared to the HBP for midbrain and cerebellum. Midbrain NE was also significantly different between the reciprocal F1's. NE concentration was then related to known behavioral characteristics in these strains.