Determining the 5-ht1receptor agonist (cp94253hydrochloride) of dorsal hippocampus (ca1) on harmaline–induced amnesia in male mice

Abstract

Background: β-Carbolines are found in cigarette smoke and cooked protein-rich foods such as meat and fish products, reflecting its formation from tryptophan by pyrolysis. β -Carbolines such as harmaline(HA) has been shown to exert multiple pharmacologic actions, including monoamine oxidase inhibition, convulsive or anticonvulsive action, and anxiolytic effects.. Harmaline has also been shown to act on a variety of receptor systems in the mammalian brain, including those for serotonin, dopamine and benzodiazepines. In animals, it has been reported to affect short and long term memory. In the present study, effects of the dorsal hippocampus 5-HT1receptor agonist (CP94253hydrochloride) on the harmaline (HA)-induced amnesia was examined in mice. Methods: In 1 experiment five groups of animals received saline (10 ml/ kg) and different doses of HA (0.625, 0.75,2 and 4 mg/kg) 15 min before testing training, In 2 experiment groups of animals received saline (10/kg, i.p.) and CP94253hydrochloride (0.0005, 0.005,0.01 and0.25 ng/mouse) 15 min before training and In 3 experiment five groups of animals received HA (0.625, .75,2 and 4 mg/kg) and CP94253hydrochloride (.25 ng/mouse) 15 min before training. Results: Male NMRI mice weighing 20-25g were used in this study. Pre-training (0.75 mg/kg) intraperitoneal (i.p.) administration of Harmalie reduced memory formation, while harmaline .625 mg/kg and 2,4 mg/kg injected intraperitoneally and pre-training did not significantly influenced on memory behavior. 5HT1B/1D agonist CP94253 hydrochloride, (.25 ng/mouse) administration had no effect on memory formation. Conclusions: The present findings suggest the involvement of agonist 5-HT1in Harmaline- induced impairment of memory formation.