Effects of 1,3,5-Trihydroxybenzene and 2,4,6-Trihydroxy-1-Propiophenone on the Smooth Muscle Organs

Although 1,2,3-trihydroxybenzene (pyrogallol) is known to inhibit the activity of catechol-o-methyltransferase (COMT) (1, 2), its clinical application is limited because of toxic effects such as formation of methemoglobin and degeneration of the kidney and liver (3).Pyrogallol has been useful only as an experimental tool to modify the metabolic process of exogenous as well as endogenous catecholamines.The present experiments were facilitated by the facts that 1,3,5-trihydroxybenzene (phloroglucinol, THB) and 2, 4, 6-trihydroxy-l-propiophenone (THPP) showed the definite spasmolytic action in ex perimental animals (4, 5) and that these compounds relieved the spastic disorders of the urinary tract, bile duct and uterus in patients (6).Based on the experimental findings that the mode of spasmolytic action is neither atropine-like, anti-histamine-like, nor pa paverine-like, Cahen (4) has suggested a direct musculotropic action of these compounds.Hattori et al. (7) have shown that trihydroxybenzenes inhibit slightly to markedly COMT 井 上 俊 一