RESUMO
The effect of bunolol on ?-adrenergic receptor of various tissues of animals were reported. The results showed that cumulative dose-response curves of isoprenaline were shifted paratlely to the right by bunolol ( 10-8, 10-7, 10-6mol/L ) on isolated rabbit atrium and guinea pig trachea preparation utilizing isoprenaline as a beta-receptor agonist. In the isolated rabbit right atrium preparation,the pA2 value of bunolol antagonizing the chronotropic action of isoprenaline was 9.3. In the isolated guinea-pig trachea preparation,the pA2 value of bunolol antagonizing the isoprenaline-induced relaxation was 9.1. By contrast, the 〔pA2 ( ?1 )- pA2 ( ?2 ) 〕 value of bunolol was 0.2, suggesting its ?-blocking action in the atrium being nearly 0,6 times more than that in the trachea. Also, comparison with pfopranolol, the blocking effect of bunolol on cardiac ?1 receptor and on trachea ?2 receptor were 4 times and 1.6 times more than that of propranolol respectively.Bunolol ( 1 mg/kg ) could, block completely the vasodilating response of epinephrine ( 10?gAg ) . At the same dosage, bunolol had no effect on blood pressure and heart rate of prior reserpini-sation rats.
RESUMO
Ansodamine(654-2)can inhibit the contractile response of the isolated ileum and trachea of Guinea-pigs induced with histamine. The cumulative logarithmic dose-response curves of histamine can be parallelly moved to the right. The PA2 values were 6.575 and 4.914 respectively.It is believed that the anti-bistamine action of ansodamine(654-2) seems to be related to the blocking of the Hi-receptors of the muscles.
RESUMO
The pharmacologic effects of verapamil (Ver) and phenylephrine(PE)on the smooth muscle of the human fallopian tube in vitro and their relationship to the stages of menstrul cycle were observed respectively. The results demonstrated that both the ampulla and isthmus of the human fallopian tube produced a contractive response to PE, which was antagonized by phentolamine. The PD_2 and PA_2 valucs were larger during the proliferative phase than during the secretory phase in the circular and longitudinal muscle of the isthmus. But there was no difference between the circular and longitudinal muscle. Ver supressed the activity of the human fallopian tuba smooth muscle and antagonized the effects of PE.The PD_2~' values were larger during the secretory phase than during the prolifertive phase. These pharmacologic characte risties of the tube indicated that d-adrenoceptor of the longitudinal muscle of the is thmus may be important, like the circular muscle in the regulation of ovum transport.