Abstracts

GABA UPTAKE IN BLOOD PLATELETS OF CHILDREN WITH ABSENCE EPILEPSY

Abstract number : 1.121
Submission category :
Year : 2003
Submission ID : 2258
Source : www.aesnet.org
Presentation date : 12/6/2003 12:00:00 AM
Published date : Dec 1, 2003, 06:00 AM

Authors :
Sirpa Rainesalo, Kai Eriksson, Pirjo Saransaari, Tapani Keranen Department of Neurology and Rehabilitation, Tampere University Hospital, Tampere, Finland; Department of Pediatric Neurology, Medical School, University of Tampere and Tampere University Hosp

[gamma]-aminobutyric acid (GABA) is the most important inhibitory neurotransmitter in the human central nervous system. Platelets have been used as a model for GABAergic neurotransmission because they display a sodium-dependent GABA uptake similar to that in neurons. In the present study, we investigated the uptake of GABA into platelets in patients with clinical presentation of typical childhood absence epilepsy (CAE) with 3 Hz spike-wave discharges in EEG. Healthy children served as controls.
The blood samples were collected from 14 patients (9 girls and 5 boys with mean age of 8 years) with CAE and eight age and sex matched controls. All patients were on antiepileptic medication; most commonly on sodium valproate or etosuximide. GABA uptake was assessed with tritium-labeled GABA as a tracer. The study was approved by the Ethics Committee of Tampere University Hospital.
GABA uptake was measured in the concentrations 5-500 [mu]M. The kinetic parameters, maximal velocity and transport constant were estimated by non-linear regression analysis. GABA uptake was faster in patients with CAE than in healthy controls.
Our preliminary results indicate marked differences in the platelet uptake of GABA between patients with CAE and healthy children. The observed peripheral alterations may indicate an impairment in the function of GABAergic systems in the brain in these patients.
[Supported by: The Medical Research Fund of Tampere University Hospital.]