EFFECT OF LOCAL AUTONOMIC DENERVATION ON IN-VITRO RESPONSIVENESS OF LYMPHOCYTES FROM RAT SUBMAXILLARY LYMPH-NODES

The local autonomic denervation of rat submaxillary lymph nodes was ac hieved by a unilateral sympathetic superior cervical ganglionectomy an d/or the unilateral section of chorda tympani (that resulted in ipsila teral parasympathetic decentralization of the submandibular territory) . This study was performed to determine: (1) whether local sympathetic and/or parasympathetic denervation of rat submaxillary lymph nodes br ought about changes in lymph node cellularity, natural killer activity and lipopolysaccharide (LPS)- and concanavalin A (Con Al-induced cell proliferation in Freund's adjuvant-injected rats; (2) whether the eff ect of the immunosuppressive drug cyclosporine in rat submaxillary lym ph nodes was affected by a single or combined unilateral ganglionectom y plus decentralization. A unilateral ganglionectomy, or the combinati on of ganglionectomy plus decentralization, performed 7 days earlier, decreased significantly cellularity in ipsilateral submaxillary lymph nodes, while a unilateral decentralization failed to affect it. Natura l killer activity increased ipsilaterally after ganglionectomy or dece ntralization, and decreased after the combined surgical procedure. LPS -induced cell proliferation augmented significantly after ganglionecto my or decentralization, while Con A-induced T lymphocyte proliferation remained unaffected. In the sham-operated side, cyclosporine decrease d submaxillary lymph node cell number and natural killer activity, whi le it increased the proliferative response to LPS, The depressive effe ct of cyclosporine on lymph node cellularity was no longer observed in ganglionectomized or decentralized lymph nodes, but was found after t he combined surgical denervation. Decentralization, or decentralizatio n plus ganglionectomy, blunted the depressive effect of cyclosporine o n natural killer activity. The stimulatory effect of cyclosporine on l ymphocyte proliferation induced by LPS was reversed both by ganglionec tomy or by decentralization and was suppressed by the combined surgica l procedure, Neither treatment affected Con A-induced proliferation of T lymphocytes. The results further indicate that an appropriate sympa thetic and parasympathetic local environment may be needed for immunom odulation, as well as for cyclosporine activity in lymphoid tissue.