Piengchai KupradinunYaninee JarratwisarutpornRawiwan WongpoomchaiHathaitip SritanaudomchaiMati RienkitjakarnNational Cancer Institute ThailandChiang Mai UniversityMahidol University2018-10-192018-10-192013-01-01Thai Journal of Veterinary Medicine. Vol.43, No.4 (2013), 589-594012564912-s2.0-84897941926https://repository.li.mahidol.ac.th/handle/20.500.14594/32807Clastogenic and anticlastogenic effects of neem flower (Azadirachta indica A. Juss) extract were determined using a rat liver micronucleus assay. Methanol extracts of neem flowers (MENF) in 15% Tween 80 at 100 and 500 mg/kg body weight were orally given to male Sprague Dawley rats daily for 6 weeks (2 weeks prior to and 4 weeks during repeated administration of diethylnitrosamine (DEN). All rats were anesthetized and their livers were collected. Hepatocytes were isolated from the livers using a collagenase solution without performing liver perfusion, then stained with 4', 6-diamidino-2-phenylindole dihydrochloride (DAPI). Incidence of the micronucleated hepatocytes was evaluated by fluorescence microscopy. Results showed that MENF had no clastogenic effects on rat hepatocytes. On the contrary, MENF at high doses significantly reduced micronucleus formation in the rat livers compared to the control group. We concluded that MENF at 100 and 500 mg/kg body weight had no clastogenic effects. Instead, it possesses anticlastogenic potential in the rat liver, particularly at high doses.Mahidol UniversityVeterinaryArticleSCOPUS