High but not low ECS stimulus intensity augments apomorphine-stimulated dopamine postsynaptic receptor functioning in rats.
BACKGROUND
Clinical research shows that the antidepressant and cognitive adverse effects of electroconvulsive therapy are both dependent on the administered electrical stimulus intensity (dose); however, dose-dependent neurotransmitter system changes in the brain, which might underlie the therapeutic or adverse effects, remain to be demonstrated.


OBJECTIVE
We used a behavioral model to examine dose-related effects of electroconvulsive shock (ECS) on dopamine postsynaptic receptor functioning in the rat brain.


METHODS
In a factorially designed study, rats (n = 100) were treated with five once-daily ECSs at three levels (sham ECS, 30 mC ECS, and 120 mC ECS), and with drug at two levels (saline, and 1 mg/kg s.c. apomorphine). Motility was assessed in the small open field.


RESULTS
Apomorphine-elicited, dopamine postsynaptic receptor-mediated hypermotility was significantly increased by 120 mC ECS but not by 30 mC ECS. An additional but unrelated finding was that, while the ECS seizure duration expectedly decreased across time, no dose-dependent effects were observed.


CONCLUSIONS
ECS-induced dopamine postsynaptic receptor up-regulation may depend on the intensity of the administered electrical stimulus.
Department of Psychopharmacology, National Institute of Mental Health and Neurosciences, Bangalore, India. andrade@nimhans.kar.nic.in
Chittaranjan
C
Andrade
Gurunath M
GM
Srinivasamurthy
A
A
Vishwasenani
G Sai
GS
Prakash
B S
BS
Srihari
J Suresh
JS
Chandra
D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects / Q000502:physiology; D004292:Dominance, Cerebral / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004565:Electroconvulsive Therapy / Q000379:methods*; D008297:Male; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology*; D017448:Receptors, Dopamine D2 / Q000187:drug effects / Q000502:physiology*; D011957:Receptors, Opioid / Q000187:drug effects / Q000502:physiology*
D011954:Receptors, Dopamine; D017448:Receptors, Dopamine D2; D011957:Receptors, Opioid; D001058:Apomorphine