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The activity of indoprophen on biliary secretion of rats has been investigated. Indoprophen, at a dose of 20 mg/kg induces a marked choleretic effect. It has been hypothesized that the choleretic action of indoprophen could be attributed to an inhibition of prostaglandin-synthetase and to an increase of cAMP which is the physiological factor responsible of ductal choleresis.

The Authors study pharmacological actions of lycorine, alkaloid of Lycoris radiata. On the basis that anti-inflammatory substances have a choleretic effect, the activity of lycorine on biliary secretion of rats has been investigated. Lycorine, at a dose of 1 mg/kg induces, in rats anaesthetized with urethane (1,2 g/kg i.m.), a marked choleretic effect. This experiment do not define the mechanism responsible for the observed choleresis.

The stimulus generated at the sinus node induces on the heart working cells a stronger contraction at higher frequences. The purpose of the present report is to investigate whether the two effects a) exicitation-contraction coupling and b) contraction strength are independent. Instead of the pace-maker it has been used a rectangular waves generator; the pulses are applied to isolated guinea-pig auricle or rat right ventricle. The AA. show a stronger twitch of cell when the membrane is depolarized without contraction. This phenomenon can be obtained as follows: by applying peculiar conditions of high frequency train pulses (so that they are not capable of eliciting contraction) or depolarizing the membrane with high KO concentration. The AA. believe that the stronger contraction of the muscle cell is due to the depolarization generated by the stimulus and it is not connected to the contraction. The potentiating factor is independent by cAMP and cytoplasmic Ca++. This factor is antagonized by propranolol.