Antihypertensive treatment with beta blockers and gabaergic transmission in rat brain.

The effects of chronic oral administration of propanolol and metoprolol on blood pressure and GABAergic function were investigated in spontaneously hypertensive rats (SHR) and compared with the effect of dihydralazine. Under the experiment conditions employed all drugs reduced significantly (p < 0.01) arterial pressure. The beta blockers elevated GABA turnover in the hypothalamus and the pons-medulla. Dihydralazine, however had not such an effect. Our result suggest that the antihypertensive action of beta blockers may be related in part to the enhanced cerebral GABAergic transmission.