Inhibitory and excitatory neurotransmitters in the cerebrospinal fluid of epileptic dogs.
OBJECTIVE
To determine concentrations of excitatory and inhibitory amino acids in CSF of a large number of dogs with idiopathic epilepsy or genetic epilepsy and to evaluate changes in CSF amino acid concentration with regard to drug treatment and sex.


METHODS
35 Labrador Retrievers with genetic epilepsy (20 male and 15 female), 94 non-Labrador Retrievers with idiopathic epilepsy (71 male and 23 female), and 20 control dogs (10 male and 10 female).


METHODS
Collection of CSF was performed > 72 hours after the occurrence of seizures. Cerebrospinal fluid concentrations of gamma-aminobutyric acid (GABA), glutamate (GLU), aspartate (ASP), serine, and glycine were determined by use of high performance liquid chromatography with electrochemical detection.


RESULTS
CSF concentrations of GABA and GLU were significantly lower in Labrador Retrievers with genetic epilepsy (LR-group dogs) than in control-group dogs or in non-Labrador Retrievers with idiopathic epilepsy (non-LR-group dogs). The GLU-to-GABA ratio was significantly higher in LR-group dogs than in non-LR-group dogs. CSF concentrations of GLU and ASP were significantly lower when all dogs with epilepsy (non-LR- and LR-group dogs combined) were compared with control-group dogs.


CONCLUSIONS
A decrease in CSF concentrations of GABA appears to play a role in the pathogenesis of genetically determined epilepsy in Labrador Retrievers. However, this decrease in CSF concentrations of GABA may also be a consequence of seizure activity. The GLU-to-GABA ratio may prove to be a useful indicator of genetic epilepsy in Labrador Retrievers.
Ellenberger
Claudia
C
Division of Clinical Neurology, Department of Clinical Veterinary Medicine, Faculty of Veterinary Medicine, University of Bern, Switzerland.
Mevissen
Meike
M
Doherr
Marcus
M
Scholtysik
Günter
G
Jaggy
André
A
D000596:Amino Acids / Q000134:cerebrospinal fluid*; D000704:Analysis of Variance; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004283:Dog Diseases / Q000134:cerebrospinal fluid*; D004285:Dogs; D004827:Epilepsy / Q000134:cerebrospinal fluid / Q000662:veterinary*; D005453:Fluorescence; D018377:Neurotransmitter Agents / Q000134:cerebrospinal fluid*; D005680:gamma-Aminobutyric Acid / Q000134:cerebrospinal fluid
D000596:Amino Acids; D018377:Neurotransmitter Agents; D005680:gamma-Aminobutyric Acid