Spinal interneurons and autonomic dysreflexia after injury

This chapter discusses the role of interneurons on autonomic dysfunction following spinal cord injury (SCI), which induces reorganization of autonomic spinal circuits resulting in increased sympathetic sensitivity, interneuron plasticity, and resultant autonomic dysreflexia (AD). Interneuron plasticity and anatomical changes following higher level SCI affect the entire autonomic nervous system, and such fluctuations are more profound following high versus lower thoracic SCI in animal models due to the greater lack of supraspinal regulation that modulates this interneuron-mediated response. Moreover, combined with maladaptive plasticity of nociceptive afferent fibers, such interneuron plasticity underlying autonomic dysfunction affects multiple organ systems including cardiovascular, thermoregulatory, bowel/bladder, and the immune systems; all of which are highlighted in this chapter in relation to the manifestation of AD.