The antiarrhythmic effect and possible ionic mechanisms of pilocarpine on animal models.

This study was designed to evaluate the effects of pilocarpine and explore the underlying ionic mechanism, using both aconitine-induced rat and ouabain-induced guinea pig arrhythmia models. Confocal microscopy was used to measure intracellular free-calcium concentrations ([Ca(2+)](i)) in isolated myocytes. The current data showed that pilocarpine significantly delayed onset of arrhythmias, decreased the time course of ventricular tachycardia and fibrillation, reduced arrhythmia score, and increased the survival time of arrhythmic rats and guinea pigs. [Ca(2+)](i) overload induced by aconitine or ouabain was reduced in isolated myocytes pretreated with pilocarpine. Moreover, M(3)-muscarinic acetylcholine receptor (mAChR) antagonist 4-DAMP (4-diphenylacetoxy-N-methylpiperidine-methiodide) partially abolished the beneficial effects of pilocarpine. These data suggest that pilocarpine produced antiarrhythmic actions on arrhythmic rat and guinea pig models induced by aconitine or ouabain via stimulating the cardiac M(3)-mAChR. The mechanism may be related to the improvement of Ca(2+) handling.

[Pilot study on comprehensive malaria control in Judong Village, Congjiang County, Guizhou Province].

OBJECTIVE: To explore the working mode of continuous malaria elimination. METHODS: Judong Village in Congjiang County, Guizhou Province, which had the highest record of malaria incidence in the history of Guizhou Province, was selected as a pilot, a comprehensive prevention and control intervention was carried out aiming at the malaria epidemic, transmission and influencing factors, and the effect was evaluated after the intervention. RESULTS: From 2015 to 2016, through those intensive measures of constructing system, improving environment and health education, the people's awareness of malaria prevention was increased, the people's enthusiasm and initiatives to participate in the prevention and control of malaria were improved in Judong Village. Meanwhile, the roads were hardened and beautified, the dispose of sewage, feces and garbage was centralized. The awareness rate of malaria prevention knowledge of residents increased to 85% to 95%, and the formation rate of anti-mosquito behavior increased to 89.66%. The density of media Anopheles reduced from 0.56 to 0.07 mosquitoes per hour each mosquito catching platform. CONCLUSIONS: A long-term mechanism for malaria prevention and control has been almost constructed in Judong Village, which facilitates the consolidation of malaria control achievements, and the progress towards malaria elimination.

Choline produces antiarrhythmic actions in animal models by cardiac M3 receptors: improvement of intracellular Ca2+ handling as a common mechanism.

It is well known that choline has protective effects on ischemic arrhythmias. We designed the present study to evaluate the antiarrhythmic effects of choline and to detect its related mechanisms in aconitine-induced rat and ouabain-induced guinea pig models of arrhythmia. Laser scanning confocal microscopy and patch-clamp technique were utilized to study the action of choline on intracellular calcium concentration and L-type calcium current (ICa-L) of cardiac myocytes. M3 receptor antagonist 4-DAMP (4-diphenylacetoxy-N-methylpiperidine-methiodide) was applied preliminarily to evaluate the role of the M3 receptor. Choline significantly increased the survival time of arrhythmic rats and guinea pigs, delayed the onset of arrhythmias and ventricular tachycardia, and decreased the arrhythmia score. The overload of intracellular Ca2+ induced by aconitine or ouabain was reduced in isolated myocytes pretreated with choline. Choline reduced the increased density of ICa-L induced by aconitine or ouabain. Moreover, the beneficial effects of choline were reversed by 4-DAMP. Choline produced antiarrhythmic actions on arrhythmia models by stimulating the cardiac M3 receptor. The mechanism may be related to the improvement of Ca2+ handling.