Left-right side-specific endocrine signaling complements neural pathways to mediate acute asymmetric effects of brain injury

Brain injuries can interrupt descending neural pathways that convey motor commands from the cortex to spinal motoneurons. Here, we demonstrate a unilateral injury of hindlimb sensorimotor rats with completely transected thoracic cord produces postural asymmetry contralateral flexion and asymmetric withdrawal reflexes within 3 hr, as well in gene expression patterns lumbar cord. The injury-induced effects were abolished by hypophysectomy mimicked transfusion serum animals brain injury. Administration pituitary neurohormones β-endorphin or Arg-vasopressin-induced side-specific responses naive animals, while antagonists opioid vasopressin receptors blocked Thus, addition well-established involvement circuits, humoral signaling may also add reflex asymmetries seen after