Local regulation of the immune response by the autonomic nervous system

The autonomic innervation of the lymphoid tissue is currently visualized as a channel for neural regulation of immunity. Several reports have dealt with the alteration of antibody responses of spleen and lymph nodes following sympathectomy, and less often, parasympathectomy. This article reviews published data on the local effects of sympathetic and parasympathetic neurons innervating immunocompetent organs on immune responsiveness. A model comprising bilateral lymphoid organs (the submaxillary lymph nodes) and the local ipsilateral manipulation of their regional sympathetic nerves (derived from the superior cervical ganglia) and of their regional parasympathetic nerves (conveyed through the lingual nerve-chorda tympani) allowed the description of purely local effects of the autonomic nerves independent of the systemic effects of the surgical manipulation itself. By employing this model, the following were observed. (1) After the unilateral sympathetic denervation of murine submaxillary lymph nodes by superior cervical ganglionectomy (SCGx), ipsilateral increases in plate-forming cell (PFC) activity, delayed hypersensitivity and graft-versus-host reactions were observed as compared to the contralateral, sham-operated, submaxillary lymph nodes. During degeneration of peripheral sympathetic nerves shortly after SCGx, PFC activity in ipsilateral submaxillary lymph nodes decreased significantly. (2) The local parasympathetic decentralization of murine submaxillary lymph nodes, achieved by the unilateral section of the chorda tympani, resulted in decreases of PFC activity, when challenged 10-20 days after denervation.(ABSTRACT TRUNCATED AT 250 WORDS)