Article

Effect of melatonin on the induction of foci of aberrant crypts in the colon by azoxymethane in rats.

Institute for Cancer Prevention, American Health Foundation Cancer Center, 1 Dana Road, 10595, Valhalla, NY, USA, .
Environmental Health and Preventive Medicine 09/2004; 9(5):234-7. DOI:10.1007/BF02898105 pp.234-7
Source: PubMed

ABSTRACT A program of research was established on the question whether melatonin played a chemopreventive role in the development of foci of aberrant crypts in the intestinal tract of male rats. Male F344 rats were injected i.p. with an aqueous solution of 15 mg/kg azoxymethane (AOM) on day 50 and day 57, and a group was also injected i.p with 0.5 mg melatonin in 0.5 ml of 10% ethanol solution 5 times per week beginning at age 47 days. Foci and multiplicity of aberrant crypts were determined after 8 weeks. These groups of animals were kept in light daily from 4∶30 to 16∶30.
In the group receiving AOM and the melatonin injections, there were fewer foci of aberrant crypts in the colon and the average number of crypts was lower after 8 weeks, compared to the group on AOM alone.
Melatonin inhibited the formation of foci of aberrant crypts in the descending colon of rats. Also, it reduced the number of aberrant crypts per focus from foci with 3 and more aberrant crypts.

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    Article: Factors associated with oxidative stress in human populations.
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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

0.5 mg melatonin
 
10% ethanol solution 5 times
 
15 mg/kg azoxymethane
 
8 weeks
 
aberrant crypts
 
age 47 days
 
AOM
 
aqueous solution
 
average number
 
intestinal tract
 
Male F344 rats
 
male rats
 
melatonin
 
melatonin injections
 
multiplicity
 
rats