Abstract
One of the side actions which restrict the clinical use of reserpine is a strong and long-lasting mental depression. Looking for other reserpine-like alkaloids less toxic and more useful for clinical trials than reserpine, Velluz et al. (1, 2) have presented 10-methoxydeserpidine (decaserpine), an isomer of reserpine.
The pharmacological effects of decaserpine have been reported in detail by Mir and Lewis (3). When the initial blood pressure of an anesthetized cat was considerably high, the intravenous injection of decaserpine caused a gradual fall and bradycardia, and increased the pressor responses to adrenaline and noradrenaline. The intraperitoneal injection of 20 mg/kg of decaserpine did cause neither ptosis, diarrhea nor sedation in rats. In mice, however, the intraperitoneal injection of 40 to 80 mg/kg of decaserpine induced drowsiness and decrease of spontaneous motor activity in a similar manner to the appropriate dose of reserpine.
On the other hand, Leroy and Schaepdryver (4) have reported that the intraperitoneal injection of 25 mg/kg of decaserpine did not affect the content of catecholamine in the brain and heart of cat 24 hours after the injection. In the previous report (5), the authors studied the time course of the depletion of noradrenaline in the brain and atrium, and of adrenaline in the adrenal glands of rabbit induced by the intravenous or intracarotid injection of reserpine.
In this report, the effects of the intravenous and intracarotid injections of decaserpine on the content of noradrenaline and adrenaline in the tissues were likewise studied in rabbits. Besides, the same effects of tetrabenazine which has been reported to deplete less catecholamine from the peripheral organs than from the brain (6, 7), and of xylopinine which has been reported to show weak sedation and a considerably strong adrenolytic action in a variety of animals (8) were studied.
