Tissue distribution of acebutolol in mature normotensive and stroke-prone spontaneously hypertensive rats.

Tissue distribution of acebutolol was studied in 33-week-old normotensive (WKY) and Okamoto stroke-prone (SHR-SP) rats, 30 min after an i.v. administration, by using 14C-acebutolol. Plasma level of acebutolol was higher in WKY than in SHR-SP. Aorta, kidney, liver and muscle radioactivity/plasma radioactivity ratios were higher in SHR-SP than in WKY. The brain/plasma radioactivity ratio was very low and similar in the two groups. The drug distribution was the same in the two groups except in medulla + corpus trapezoides where drug concentration was greater in SHR-SP. These results, compared with previous ones, show an age-related evolution in pathological state in SHR-SP. They point out a specific concentration of the beta-blocking drug in a defined part of the brain, namely medulla + corpus trapezoides.