High 3H-vesamicol binding in ALS motor neurons--autoradiographic visulalization of hyperactivities?
OBJECTIVE
To evaluate if increased metabolic demand in remaining motor neurons in ALS spinal cord sections can be visualized by 3H-vesamicol binding.


METHODS
As a presumed marker of the vesicular acetylcholine transporter, 3H-vesamicol was applied in quantitative autoradiography in cervical spinal cord sections from 11 ALS patients and 4 control cases. The regional binding was compared to that of the muscarinic ligand 3H-QNB.


RESULTS
Our results demonstrate the same magnitude of H-vesamicol binding in the ventral horn of ALS spinal cord as compared to controls, despite the profound loss of motor neurons in that specific area in ALS. The specificity of 3H-vesamicol binding for the cholinergic transporter is high in the motor neuron area, and sigma-sites constitute a minor proportion.


CONCLUSIONS
The lack of decrease in 3H-vesamicol binding in postmortem ALS spinal cord sections probably reflects an upregulated synthesis of vesicular membranes in remaining and hyperactive motor neurons in vivo.
Grundström
E
E
Dept. of Neurology, University Hospital, Uppsala, Sweden.
Gillberg
P G
PG
Aquilonius
S M
SM
D001345:Autoradiography; D002352:Carrier Proteins / Q000378:metabolism*; D004734:Energy Metabolism / Q000502:physiology*; D006801:Humans; D026901:Membrane Transport Proteins; D016472:Motor Neuron Disease / Q000473:pathology*; D009046:Motor Neurons / Q000473:pathology*; D009467:Neuromuscular Depolarizing Agents / Q000493:pharmacokinetics*; D010880:Piperidines / Q000493:pharmacokinetics*; D012016:Reference Values; D013116:Spinal Cord / Q000473:pathology; D014316:Tritium; D050494:Vesicular Acetylcholine Transport Proteins; D033921:Vesicular Transport Proteins
D002352:Carrier Proteins; D026901:Membrane Transport Proteins; D009467:Neuromuscular Depolarizing Agents; D010880:Piperidines; C493459:SLC18A3 protein, human; D050494:Vesicular Acetylcholine Transport Proteins; D033921:Vesicular Transport Proteins; D014316:Tritium; C006189:vesamicol