Chronotropic responses to acetylcholine in atria of mice chronically infected with Y and CL strains of Trypanosoma cruzi.

Cardiac parasympathetic denervation has been reported to occur in human and experimental T. cruzi infections. We have used acetylcholine to investigate the in vitro chronotropic sensitivity of atrial muscarinic receptors in mice chronically infected with either a reticulotropic (Y) or a myotropic (CL) strain of T. cruzi. The dose-response curves did not differ from that obtained for control mice, a result that may be due to reinnervation processes.