The effect of nicotine on intra-axonal transport in cholinergic motor neurons of the rat; influence of acutely administered, non-toxic doses.
The intra-axonal transport of acetylcholine (ACh) and ACh-metabolizing enzymes in rat sciatic nerves was studied following nicotine treatment. The nicotine was administered in a low dose (30 mug/kg) s.c. every second h for 18-22 h, to mimic the serum-concentrations of a cigarette smoker. Control rats received s.c. injections of the vehicle. The main effects were observed regarding the ACh-esterase (AChE) activity. In unoperated nerves the level was decreased by about 10%. In 12 h crushed nerves the accumulation of enzyme activity proximal to the crush was markedly reduced in the nicotine-treated group, indicating a reduction in amount of proximo-distally transported enzyme activity. The ACh-levels were unchanged except at 12 h postoperatively when a small increase proximal to the crush was observed. The choline-acetyl transferase (CAT) activity in unoperated nerves was similar in both groups of rats; the 7 h accumulation above the crush, however, was somewhat reduced after nicotine treatment. The possible causes of the observed nicotine induced changes are so far not known.
D000109:Acetylcholine / Q000378:metabolism*; D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D001369:Axons / Q000378:metabolism*; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D008297:Male; D009046:Motor Neurons / Q000378:metabolism*; D009538:Nicotine / Q000008:administration & dosage / Q000494:pharmacology*; D010275:Parasympathetic Nervous System / Q000378:metabolism*; D051381:Rats; D012584:Sciatic Nerve / Q000378:metabolism
D009538:Nicotine; D002795:Choline O-Acetyltransferase; D000110:Acetylcholinesterase; D000109:Acetylcholine