Author(s): Lukoyanov, NV ; Watanabe, H ; Carvalho, LS ; Kononenko, O ; Sarkisyan, D ; Zhang, M ; Andersen, MS ; Lukoyanova, EA ; Galatenko, V ; Tonevitsky, A ; Bazov, I ; Iakovleva, T ; Schouenborg, J ; Bakalkin, G
Date: 2021
Persistent ID: https://hdl.handle.net/10216/153765
Origin: Repositório Aberto da Universidade do Porto
Subject(s): Brain injury; Left-right side; Neuroendocrine signaling; Neurohormones; Neuroscience; Nociceptive withdrawal reflex; Postural asymmetry; Rat
Brain injuries can interrupt descending neural pathways that convey motor commands from the cortex to spinal motoneurons. Here, we demonstrate that a unilateral injury of the hindlimb sensorimotor cortex of rats with completely transected thoracic spinal cord produces hindlimb postural asymmetry with contralateral flexion and asymmetric hindlimb withdrawal reflexes within 3 hr, as well as asymmetry in gene expression patterns in the lumbar spinal cord. The injury-induced postural effects were abolished by hypophysectomy and were mimicked by transfusion of serum from animals with brain injury. Administration of the pituitary neurohormones b-endorphin or Arg-vasopressin-induced side-specific hindlimb responses in naive animals, while antagonists of the opioid and vasopressin receptors blocked hindlimb postural asymmetry in rats with brain injury. Thus, in addition to the well-established involvement of motor pathways descending from the brain to spinal circuits, the side-specific humoral signaling may also add to postural and reflex asymmetries seen after brain injury.
