The effect of drugs acting on CCK receptors and rat free exploration in the exploration box.
The effects of cholecystokinin (CCK) CCKA receptor antagonist devazepide (10 micrograms/kg and 1.0 mg/kg), CCKB receptor antagonist L 365260 (1.0 mg/kg), and CCKB receptor agonist CCK tetrapeptide (CCK-4, 75 micrograms/kg), and their concomitant administration with antidepressants desipramine (10 mg/kg) and citalopram (10 mg/kg) on rat exploratory behaviour were studied in the recently developed exploration box test. In addition, the effects of repeated administration of despiramine (10 mg/kg) and citalopram (10 mg/kg) were studied. After acute administration, CCK-4 decreased significantly the number of line crossings, rears, investigative approaches, and the time spent exploring. The time of latency and the number of entries into large arena were unchanged. Desipramine reduced all observed criterions of rat behaviour, but citalopram was ineffective. Devazepide (1.0 mg/kg) and L 365260 (1.0 mg/kg) had no effect on rat behaviour after acute or repeated administration. L 365260 (1.0 mg/kg) blocked the antiexploratory effect of CCK-4, whereas devazepide (10 micrograms/kg) did not. No interaction of CCK-4, devazepide, or L 365260 treatment with antidepressant treatment was found. Our results suggest that the administration of a CCKB agonist diminishes rat exploratory behaviour, but neither CCKA nor CCKB receptor blockade induces changes on rat exploratory behaviour in the free exploration paradigm.
Matto
V
V
Department of Pharmacology, University of Tartu, Estonia.
Harro
J
J
Allikmets
L
L
D018759:Adrenergic Uptake Inhibitors / Q000494:pharmacology; D000818:Animals; D001007:Anxiety / Q000523:psychology; D001570:Benzodiazepinones / Q000494:pharmacology; D015283:Citalopram / Q000494:pharmacology; D003891:Desipramine / Q000494:pharmacology; D020109:Devazepide; D005106:Exploratory Behavior / Q000187:drug effects*; D005260:Female; D006727:Hormone Antagonists / Q000494:pharmacology; D010671:Phenylurea Compounds; D051381:Rats; D017208:Rats, Wistar; D011949:Receptors, Cholecystokinin / Q000037:antagonists & inhibitors / Q000187:drug effects*; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology
D018759:Adrenergic Uptake Inhibitors; D001570:Benzodiazepinones; D015283:Citalopram; D003891:Desipramine; D020109:Devazepide; D006727:Hormone Antagonists; D010671:Phenylurea Compounds; D011949:Receptors, Cholecystokinin; D017367:Selective Serotonin Reuptake Inhibitors; C058121:L 365260