抄録
The absorption, distribution, excretion and metabolism of ^<14>C-HOPA were studied in rats and mice following oral administration. When ^<14>C-HOPA was administered orally to rat, the radioactivity was absorbed rapidly from the digestive tract, the half-life for absorption being 110 minutes. Thirty minutes after oral administration of ^<14>C -HOPA in mice, the concentration of the radioactivity was conspicuous in the liver and kidney, and moderate in the testis, muscle and spleen, and that in the brain was extremely low. The autoradiographic distribution pattern of ^<14>C -HOPA was similar to that of intravenous route. The highest concentration of the radioactivity in the brain of rats reached 3 hours after oral administration, and the amount of HOPA was 1.4 μg per gram of the wet weight. Sixty-five percent of the radioactivity of ^<14>C-HOPA was excreted in urine of rats within 48 hours and 28.5% in feces. Ninty-eight percent of the urinary radioactivity accounted for unchanged ^<14>C-HOPA and 2.0% accounted for an unknown metabolite.
