Glutamate Uptake in Blood Platelets of Epileptic Patients.
Abstract number :
2.045
Submission category :
Year :
2001
Submission ID :
283
Source :
www.aesnet.org
Presentation date :
12/1/2001 12:00:00 AM
Published date :
Dec 1, 2001, 06:00 AM
Authors :
S. Rainesalo, MD, Neurology and Rehabilitation, University Hospital of Tampere, Tampere, Finland; P. Saransaari, PhD, Brain Recearch Center, Tampere University, Tampere, Finland; J. Peltola, MD, Neurology and Rehabilitation, University Hospital of Tampere
RATIONALE: Excitatory amino acid glutamate (GLU) is in involved in epileptogenesis, in initiation and spread of seizures, and in seizure-related neuronal damage. Only limited data exist on markers of excitatory neurotransmission in human epilepsy. Human platelets have been shown to accumulate GLU in manner similar to synaptosomal preparations. We assessed the uptake of GLU in platelets of patients with two different epileptic syndromes.
METHODS: We studied the uptake of GLU in platelets in 20 patients with juvenile myoclonic epilepsy (JME), in 20 patients with temporal lobe epilepsy and hippocampal sclerosis (TLE+HS) and in 20 healthy volunteers. All the patients were on antiepileptic drug treatment. The patients and volunteers were matched for age and sex. GLU uptake was assessed with tritium-labeled GLU as a tracer.
RESULTS: The uptake of GLU was measured in the concentration range of 5-500 mM. The kinetic parameters, maximal velocity and transport constant were estimated by non-linear regression analysis. The uptake of GLU was fastest in the TLE+HS patients. JME patients did not differ from volunteers.
CONCLUSIONS: Altered GLU uptake was seen only in patients with TLE+HS. It remains unclear whether the alteration in uptake results in changes of synaptosomal or extracellular levels of GLU.