[Correlation between motor paralysis and neurotoxicity induced by intrathecal dynorphin A (1-17) in rats].
Intrathecal(i.t.) injection of 10 microliters of dynorphin A(1-17) 20 nmol.L-1 per rat resulted in irreversible hind limb paralysis and suppression of the tail-flick reflex lasting for up to 40 h. The dual effects of dynorphin appeared 5-10 min after the i.t. administration. Histologic examination of the spinal cord in the rats demonstrated dead and/or dying and degenerated motor-neurons in the ventral horn located predominately in the lumbar segment(a 87.2% reduction of the number of motor neurons, P < 0.01) and also in a lesser degree in sacral segment(-69.6%, P < 0.05). The thoracic segment was essentially normal(-8.2%, P > 0.05).
Cui
C L
CL
Neuroscience Research Center, Beijing Medical University, Beijing 100083.
Wu
L Z
LZ
Han
J S
JS
D000818:Animals; D004399:Dynorphins / Q000008:administration & dosage / Q000633:toxicity*; D006614:Hindlimb; D007278:Injections, Spinal; D008297:Male; D009046:Motor Neurons / Q000187:drug effects; D010243:Paralysis / Q000139:chemically induced*; D051381:Rats; D017208:Rats, Wistar; D013116:Spinal Cord / Q000187:drug effects*
D004399:Dynorphins