ISSN:
1432-1106
Keywords:
Ca++ selective microelectrodes
;
Ca++ activity
;
K+ activity
;
Seizure
;
Cerebral cortex
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Extracellular calcium and potassium activities (aCa and aK) as well as neuronal activity were simultaneously recorded with ion-sensitive electrodes in the somatosensory cortex of cats. Baseline aCa was 1.2–1.5 mM/1, baseline a k 2.7–3.2 mM/1. Transient decreases in aCa and simultaneous increases in aK were evoked by repetitive stimulation of the contralateral forepaw, the nucleus ventroposterolateralis thalami and the cortical surface. Considerable decreases in aCa (by up to 0.7 mM/1) were found during seizure activity. A fall in aCa preceded the onset of paroxysmal discharges and the rise in aK after injection of pentylene tetrazol. The decrease in aCa led also the rise in aK during cyclical spike driving in a penicillin focus. It is concluded that alterations of Ca++ dependent mechanisms participate in the generation of epileptic activity.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00235500
Permalink
