From a study by Denetsu Sutoo and Kayo Akiyama:
The mechanism by which music modifies brain function is not clear. Clinical findings indicate that music reduces blood pressure in various patients. We investigated the effect of music on blood pressure in spontaneously hypertensive rats (SHR). Previous studies indicated that calcium increases brain dopamine (DA) synthesis through a calmodulin (CaM)-dependent system. Increased DA levels reduce blood pressure in SHR. In this study, we examined the effects of music on this pathway. Systolic blood pressure in SHR was reduced by exposure to Mozart’s music (K.205), and the effect vanished when this pathway was inhibited. Exposure to music also significantly increased serum calcium levels and neostriatal DA levels. These results suggest that music leads to increased calcium/CaM-dependent DA synthesis in the brain, thus causing a reduction in blood pressure. Music might regulate and/or affect various brain functions through dopaminergic neurotransmission, and might therefore be effective for rectification of symptoms [emphasis added] in various diseases that involve DA dysfunction.
Even rats like Mozart, apparently. Their systolic blood pressure was reduced because music increases calcium levels in the brain, when more calcium is available, more dopamine is produced, and blood pressure decreases.
So if you’re got high blood pressure, it might be worth turning the dial on your radio, or your computer, to the nearest classical station and see what happens!