Increasing CNS norepinephrine levels by the precursor L-DOPS facilitates beam-walking recovery after sensorimotor cortex ablation in rats.
The present investigation was conducted to document a role of L-threo-3,4-dihydroxyphenylserine (L-DOPS), precursor of L-norepinephrine (NE), in the functional recovery from beam-walking performance deficits in rats after unilateral sensorimotor cortex ablation. L-DOPS was administered simultaneously with benserazide (BSZ; a peripheral aromatic amino acid decarboxylase inhibitor), and the regional contents of NE in the cerebral cortex, hippocampus, and cerebellum were assayed. Behavioral recovery was demonstrated by the rats treated with L-DOPS and BSZ, and the rate of recovery was significantly different from that of either BSZ-treated or vehicle-treated control rats. The NE tissue levels in the three discrete regions of the rat brain were significantly elevated in the experimental rats receiving both L-DOPS and BSZ. The present studies indicate that increasing NE levels by the precursor L-DOPS may be responsible for facilitating behavioral recovery from beam-walking performance deficits in rats, and further suggest that L-DOPS may become one of the candidate compounds for further clinical human trials promoting functional recovery after injuries to the cerebral cortex.
Kikuchi
K
K
Department of Neurosurgery, Akita University School of Medicine, 1-1-1 Hondo, Akita, Japan.
Nishino
K
K
Ohyu
H
H
D000818:Animals; D000978:Antiparkinson Agents / Q000494:pharmacology; D065105:Aromatic Amino Acid Decarboxylase Inhibitors; D001545:Benserazide / Q000494:pharmacology; D001921:Brain / Q000378:metabolism*; D020208:Brain Injury, Chronic / Q000150:complications*; D002531:Cerebellum / Q000378:metabolism; D002540:Cerebral Cortex / Q000378:metabolism; D004292:Dominance, Cerebral; D015103:Droxidopa / Q000494:pharmacology* / Q000627:therapeutic use; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006429:Hemiplegia / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D006624:Hippocampus / Q000378:metabolism; D008297:Male; D009044:Motor Cortex / Q000293:injuries*; D009638:Norepinephrine / Q000096:biosynthesis / Q000502:physiology*; D011597:Psychomotor Performance / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013003:Somatosensory Cortex / Q000293:injuries*
D000978:Antiparkinson Agents; D065105:Aromatic Amino Acid Decarboxylase Inhibitors; D004791:Enzyme Inhibitors; D001545:Benserazide; D015103:Droxidopa; D009638:Norepinephrine