Increased methionine-enkephalin levels in genetically epileptic (tg/tg) mice.
Recent experimental data indicate that endogenous brain ligands for the opioid receptors such as enkephalins, beta-endorphin (beta-End) and dynorphin (Dyn) may be involved in both generalized and partial seizures. The "tottering" (tg/tg) mouse provides an electrophysiological representation of generalized spontaneous human epilepsy. These mice exhibit behavioral absence seizures with accompanying spike-wave discharges. Methionine-enkephalin (M-Enk), beta-End and Dyn levels in various regions of brain were measured by radioimmunoassay (RIA) in 15-18-week-old tg/tg and control (+/+) mice to elucidate the relation between seizures and the opioid system. beta-End and Dyn levels were similar in tg/tg and +/+ mice. However, M-Enk levels were significantly increased in the striatum, cortex, pons and medulla of the tg/tg mice. Our data suggest that in the tottering mouse model of generalized epilepsy there is an alteration of enkephalinergic pathways and not of the endorphinergic or dynorphinergic pathways.
Department of Pathology, Indiana University School of Medicine, Indianapolis 46202-5120.
V K
VK
Patel
L C
LC
Abbott
A K
AK
Rattan
G A
GA
Tejwani
D000818:Animals; D001921:Brain / Q000378:metabolism; D004399:Dynorphins / Q000378:metabolism; D004744:Enkephalin, Methionine / Q000378:metabolism*; D004827:Epilepsy / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008818:Mice, Neurologic Mutants; D009994:Osmolar Concentration; D011863:Radioimmunoassay; D014018:Tissue Distribution; D001615:beta-Endorphin / Q000378:metabolism
D004744:Enkephalin, Methionine; D001615:beta-Endorphin; D004399:Dynorphins