Brain distribution of propranolol in the rat

The distribution and kinetics of D,L-propranolol in rat brain were examined after an intravenous injection of the drug. Measurements in brain areas and blood were performed by means of a sensitive and specific gas liquid chromatographic method. The disappearance rate in cortical areas paralleled that in blood. However D,L-propranolol decreased at a slower rate in hypothalamic and medullary nuclei. Since propranolol is believed to have central hypotensive effects, its retention by certain central nuclei involved in blood pressure regulation is of interest.