The possible involvement of different neurotransmitter systems in the anxiogenic action of cholecystokinin octapeptide sulphate ester (CCK-8) was investigated in rats. Intracerebroventricularly (i.c.v.) administered CCK-8 induced an anxiogenic response in an elevated plus-maze test. Pretreatment with dopaminergic, muscarinergic acetylcholine receptor blockers and an opiate receptor antagonist blocked the anxiogenic response to CCK-8. The α and β adrenoreceptor, the GABA receptor and the 5-hydroxytryptamine (5-HT) receptor blockers were not able to modulate the 'anxiogenic-like' effect of CCK-8. The results suggest that the anxiogenic effects of CCK-8 are mediated via different neurotransmitters and the anxiogenic action can be prevented by receptor blockers to these transmitters.
ASJC Scopus subject areas
- Endocrine and Autonomic Systems
- Cellular and Molecular Neuroscience