Catecholamine overflow within rat striatum: the influence of microstimulation and electroconvulsive stimulation as observed with voltammetry.
Differential pulse voltammetry with a carbon fibre microelectrode was used in chloral hydrate-anaesthetized rats for testing the influence of microstimulation and of electroconvulsive stimulation on the changes in concentration of electro-oxidizable materials (catechol derivates) in the extracellular space of the corpus striatum. Microstimulation applied in the striatum (8 V anodal pulses, 0.1 ms, 100 Hz for 40 s) caused a significant increase of the catechol-oxidative current (Ico); 5 s after microstimulation was stopped Ico ranged from 117 to 141% of the control (all values means +/- S.D. unless otherwise stated; 124 +/- 11%, n = 4, P < or = 0.01, Student's t test). This effect ceased in the third minute after microstimulation. A comparable result was observed when microstimulation was repeated at intervals of 10 min. Electroconvulsive stimulation with a sinusoidal current (50 Hz, approximately 150 mA, 0.2 s) caused a large increase in Ico; 20 s after stimulation ceased, Ico was 987 +/- 90% (n = 3) of the control and it returned to the baseline 2 min later. The mechanisms inducing transmitter overflow are considered and the influence of electroconvulsive stimulation on the striatum is discussed in the context of its beneficial effects in psychopathic patients.
Pavlásek
J
J
Department of Neurophysiology, Slovak Academy of Sciences, Bratislava.
Masánová
C
C
Haburcák
M
M
Murgas
K
K
D000818:Animals; D002395:Catecholamines / Q000378:metabolism*; D003342:Corpus Striatum / Q000378:metabolism*; D004558:Electric Stimulation / Q000295:instrumentation / Q000379:methods*; D004594:Electrophysiology / Q000379:methods; D004597:Electroshock; D008839:Microelectrodes; D009994:Osmolar Concentration; D051381:Rats
D002395:Catecholamines