Effects of ethylcholine mustard aziridinium ion (AF64A) on contractile responses to agonists or transmural nerve stimulation (TNS) were examined in rat iris sphincter muscle.The responses to TNS of isolated sphincter muscle were abolished within 1 hr after the addition of 0.1 mM AF64A to the bathing solution, while responses to acetylcholine (ACh) and 5-hydroxytryptamine (5-HT) were not changed significantly. In sphincter muscles which were isolated 3 days after the micro-injection of 100 nmol AF64A into the anterior chamber of eyes in vivo, the response to TNS were decreased to about 30% of the control.The injection of AF64A at higher concentrations often resulted in serious chronic damage of the eye. When 100 nmol AF64A was injected twice with an interval of 3 days, the response to TNS was decreased to about 20% of the control. Maximum responses and sensitivities to ACh and 5-HT were markedly enhanced in sphincters from eyes which had been treated with AF64A twice. The sensitivity of depolarized sphincters to external Ca2+ was also increased significantly. Seven weeks after the second injection, responses to TNS recover ed to more than 50% of the control and the effects of AF64A mostly disappeared. In conclusion, the acute inhibition of parasympathetic transmission without postsynaptic changes can be achieved within 1 hr after bath-application of 0.1 mM AF64A. The reduc tion of parasympathetic nerve activity by treatment with AF64A in vivo induces nonspecific supersensitivity in iris sphincter, whereas effects of AF64A were mostly reversible under the present experimental conditions.

A work sampling method was applied to provide a description of the tasks performed by staff members in the hospital pharmacy drug information center of the University of Tokyo. A total of 1090 observations were recorded during 13 days in 3-week period on each of the three pharmacists and a part-timer. Productive time was 78% of the total time. The collection and distribution of drug information occupied 60% and 36% of productive time, respectively.