Pharmacological properties of procaterol, a newly synthetized, specific beta 2-adrenoceptor stimulant. Part I. Effects on the CNS (author's transl)]

Effects of procaterol (PRO) on the CNS were investigated in comparison with those of salbutamol (SAL) and isoproterenol (ISO). PRO, 15 to 50 mg/kg given subcutaneously suppressed spontaneous movement in mice, rats and rabbits and with a large dose, 1000 mg/kg, the animals became quiet and immobile. In dogs, PRO produced similar symptoms and in addition, there was nausea and vomiting. The animals recovered within 3--8 hours. ID50's in depressing spontaneous movement were 20.2 and 245 mg/kg for PRO, 51.1 and 133 mg/kg for SAL and 2.37 and 143 mg/kg for ISO, respectively, both by the subcutaneous and oral routes of administration. Methamphetamine induced increase in motility and fighting behavior was also suppressed by PRO when similar doses were given. PRO had no effect on coordinating movement, halothane anesthesia, drug and electric stimulation induced convulsions and body temperature, and there was no muscle relaxant action. However, PRO in large doses prolonged sleeping time with hexobarbital. The analgesic effect of PRO was not observed with Haffner's and Landall Selitto's methods but acetic acid induced writhing was suppressed by PRO. PRO had little effect on spontaneous EEGs either cortical or from deep structures, and EEG arousal responses. The effects of PRO on the CNS were slight and nonspecific, and similar to those of SAL and ISO.