Reversal of scopolamine-induced amnesia in rats by the neuroleptic zuclopenthixol: underlying monoaminergic and cholinergic mechanisms

Introduction: the effects of different antipsychotic medications on impaired cognitive function are rarely investigated despite the common co-existence of psychosis with dementia. Zuclopenthixol acetate is an antipsychotic agent that has been recently reported to facilitate cognitive function of experimental animals. This study aimed at investigating the effect of zuclopenthixol on scopolamine-induced amnesia in rats

Methods: two doses of zuclopenthixol [0.7 and 1.4 mg/kg i.p.1, devoid of any effect on the locomotors activity of animals, were evaluated in a step-through passive avoidance paradigm of memory function. Administration of zuclopenthixol [0.7 and 1.4 mg/kg i.p.] 30 min before scopolamine injection caused a significant increase in step-through latency during retrieval testing compared to scopolamine-treated animals. The effect of such antiamnestic doses of zuclopenthixol on monoamines' and acetylcholinesterase enzyme [ChE] leveuactivity in hippocampus and cortex of rats was then evaluated

Results: both doses of zuclopenthixol were shown to reduce hippocampal ChE activity while elevating hippocampal norepinephrine [NE] and cortical dopamine [DA] levels. In addition, the lower dose of zuclopenthixol reduced hippocampal serotonin [5-HT] level

Conclusion: zuclopenthixol was shown in this study to reverse scopolamine-induced amnesia possibly through modulating cortical/hippocampal monoaminergic neurotransmission and/or ChE activity

Effect of ozone on the viability of some protozoa in drinking water

In this study, water samples from household tanks in several districts of Alexandria were examined for protozoa contamination and studying the effect of ozone and chlorine on their viability. The parasitic protozoa encountered were Giardia, Cryptosporidia, Blastocystis, Cyclospora and Microsporidia. Distilled water was treated by ozone or chlorine. Ozonated water samples were prepared at a concentration of 1 ppm after contact times with ozone of three, five, seven and nine minutes. Chlorine concentrations were 4 and 8 ppm. Parasites were incubated overnight at room temperature with the treated distilled water. The viability of the parasites was assessed by examining the intestinal sections of the infected animals