The Effects of Electroshock Convulsions on Calcium Transport within Synaptic Terminals |
| |
| Authors: | A V Delgado-Escueta S Victor D Davidson |
| |
| Institution: | Membrane Physiology Laboratories, Neurology and Research Services, V.A. Wadsworth Medical Center and The Reed Neurological Research Center, and Brain Research Institute, U.C.L.A. School of Medicine, LOS Angeles, Colifornia, 90025, U. S. A. |
| |
| Abstract: | Abstract: Calcium transport was assessed within synaptic terminals isolated from cerebral cortices of rats which experienced one maximal electroshock (ES) convulsion daily. No significant change in calcium content (Ca1)] of synaptosomes was present after 2 consecutive days of maximal convulsions. After 4 and 6 days of maximal seizures, (Ca1) rose 20% and 37%, respectively. 15Ca2+ influx within synaptosomes in vitro increased after 6 days of ES convulsions (1.94 ± 0.4 μmol/g protein/min in ES convulsions versus 1.54 ± .03 μmol/g protein/min in controls). The higher rate of 45Ca2+ influx in convulsed animals was accounted for by elevated internal sodium (Na1)] values. Maximal 45Ca2+ efflux decreased after ES convulsions (0.48 μmol/g protei/min in ES convulsions versus 0.8 μmol/g protei/min in controls). The slower rate of 45Ca2+ efflux after convulsions was also accounted for by elevated (Na1). Our results suggest that (Ca1) increased within synapses after in vivo ES convulsions secondary to a primary ionic event, namely, elevated (Na1). |
| |
| Keywords: | |
|
|
