Effect of parasympathetic decentralization on interferon-gamma release from rat submandibular lymph nodes in vitro

The aim of this study was to examine the regulation of interferon (IFN)-gamma release by cells from submandibular lymph nodes of rats subjected to a unilateral parasympathetic decentralization by severing the ipsilateral chorda tympani 7 days earlier. Cells obtained from contralateral sham-operated submandibular lymph nodes were employed as control. Parasympathetic decentralization of lymph nodes resulted in significantly less IFN-gamma release as compared to that found in innervated lymph nodes. Mitogens (lipopolysaccharide, concanavalin A) stimulated IFN-gamma release in cells derived from the innervated lymph nodes only. The muscarinic agonist metacholine decreased IFN-gamma release in cells derived from innervated lymph nodes. At the highest concentration employed (10−4 M), metacholine suppressed the stimulatory effect of mitogens on IFN-gamma release in cells of innervated lymph nodes while the muscarinic antagonist atropine (10−8–10−4 M) lacked to affect IFN-gamma release. Addition of nicotine (10−5–10−3 M) failed to modify IFN-gamma release. The results support the occurrence of significant effects of local parasympathetics in modulating IFN-gamma release by submandibular lymph nodes.