Binding of Nicotinic Ligands to and Nicotine-Induced

MARIANA BOLLO, GRACIELA VENERA, MIRTHA BISCOGLIO DE JIMENEZ BONINO,AND ESTELA MACHADO-DOMENECH.

BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS

Elseiver

Lugar: Amsterdam; Año: 2001 vol. 281 p. 300 - 304

0006-291X

This work provides evidence that nicotine (1 x10-5 M) can cause changes in the intracellular calciumconcentration of Trypanosoma cruzi epimastigotes,which can be blocked by a-bungarotoxin butnot by atropine. Moreover, parasite membranes alsobind such nicotinic acetylcholine receptor antagonistas well as agonists such as carbamylcholine(IC50: 7.6 x10-7 M) and nicotine (IC50: 1 x 10-7 M). Results suggest that there is a molecular species inthe surface of the parasite able to bind nicotinicligands; therefore, nicotine interaction could lead tothe activation of the mechanisms involved in intracellularcalcium concentration increase in the parasite. © 2001 Academic Press Key Words: Trypanosoma cruzi; nicotinic ligands; nicotine; a-bungarotoxin; calcium; carbamylcholine.