Identification of antibodies with muscarinic cholinergic activity in human Chagas' disease: pathological implications

J Auton Nerv Syst. 1994 Apr;47(1-2):45-52. doi: 10.1016/0165-1838(94)90064-7.


We examined the possible role of altered humoral immunity in dysautonomic syndrome in Chagas' disease by analyzing the effect of sera and IgG on the binding of radioligand to heart muscarinic cholinergic receptors and on the contractility of myocardium. Human Chagasic IgG inhibited in a non-competitive manner the binding of [3H]quinuclidinyl benzilate to the cardiac cell membrane. Moreover, human Chagasic IgG behaved as a partial muscarinic cholinergic agonist, reducing heartcontractility and inhibiting the action of pilocarpine. The prevalence of the cholinergic antibody activity was higher in sera from T. cruzi-infected asymptomatic individuals with dysautonomic syndrome than in those without autonomic nervous system alterations. The presence of these antibodies could explain the progressive receptor blockade in the parasympathetic branch of the autonomic nervous system, leading to dysautonomia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies / physiology*
  • Antibody Formation / physiology
  • Autonomic Nervous System Diseases / etiology
  • Autonomic Nervous System Diseases / immunology
  • Autonomic Nervous System Diseases / pathology
  • Cell Membrane / metabolism
  • Chagas Disease / complications
  • Chagas Disease / immunology*
  • Chagas Disease / pathology
  • Erythrocytes / immunology
  • Erythrocytes / metabolism
  • Humans
  • Immunoglobulin G / immunology
  • In Vitro Techniques
  • Male
  • Myocardial Contraction / drug effects
  • Pilocarpine / pharmacology
  • Quinuclidinyl Benzilate
  • Rats
  • Receptors, Muscarinic / immunology*
  • Turkeys


  • Antibodies
  • Immunoglobulin G
  • Receptors, Muscarinic
  • Pilocarpine
  • Quinuclidinyl Benzilate