Activation of nitric oxide signaling through muscarinic receptors in submandibular glands by primary Sjogren syndrome antibodies

PEREZ LEIROS C; STERIN BORDA L; HUBSCHER O; ARANA R; BORDA E

CLINICAL IMMUNOLOGY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Año: 1999 vol. 90 p. 190 - 195

1521-6616

Primary Sjogren Syndrome is a chronic autoimmune disease characterized by exocrine gland dysfunction. Here we present evidence of the activation of nitric oxide signaling cascade by circulating antibodies of patients with Sjo¨gren Syndrome in rat submandibular glands. Constitutive nitric oxide synthase and cyclic GMP levels are modulated by Sjo¨gren IgGs through the activation of muscarinic acetylcholine receptors on the glands. The effects are similar to those produced by the agonist carbachol and blocked by the antagonist atropine. The involvement of M1 subtype of muscarinic receptors is proposed since both a synthetic peptide homologous to an extracellular domain of M1 receptor and pirenzepine, a selective M1 antagonist, partially blocked the effects. We conclude that Sjo¨gren Syndrome antibodies can activate nitric oxide signaling in submandibular glands by interacting with muscarinic acetylcholine receptors