Neural regulation of the immune system modulates hypertension-induced target-organ damage

Innate and acquired immune mechanisms are involved in hypertension-induced target-organ damage. Immunosuppressive treatments directed at T lymphocytes, NF-κB activation, or tumor necrosis factor-alpha production are all successful in ameliorating cardiac or renal injury. Recently, important modulatory functions involving the autonomic nervous system have been uncovered. Involved are an afferent detection arm that sends vagal-mediated signals to the brain and an efferent arm that includes the spleen and important nicotinic acetylcholine receptor subunit. The signaling attenuates inflammatory activity. Splenectomy or operations that injure the vagus or splenic abrogate these important protective mechanisms. Vagal stimulation, either electrical or pharmacological, could provide additional protection. The field of neuroimmunology will become increasingly important to cardiovascular clinicians.