Role of pineal melatonin and melatonin-induced-immuno-opioids in murine leukemogenesis.
The relationship between the pineal gland, melatonin and melatonin-induced-immuno-opioids with the response of C57Bl/6 mice to A-RadLV induced T cell lymphomas was investigated. Mice were injected at day 0 with A-RadLV and from day 10 they were treated chronically with melatonin 4 mg/kg body weight, naltrexone 1 mg/kg or phosphate buffered saline, throughout the experiment. In another protocol, groups of mice were a) surgical pinealectomized at day-14, b) functional pinealectomized (24:24 hours light) from day -20 and c) sham pinealectomized. At day 0 each group was inoculated intrathymically with A-RadLV. The results show that melatonin accelerated (p < 0.005) leukemogenesis whereas the surgical pinealectomy and the functional pinealectomy delayed it (p < 0.005 and p < 0.01). Moreover, the action of melatonin was blocked by naltrexone (p < 0.005), indicating the involvement of melatonin-induced-immuno-opioids in the development of the lymphomas.
Conti
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A
Laboratory for Experimental Pathology, Istituto Cantonale di Patologia, Locarno, Switzerland.
Haran-Ghera
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N
Maestroni
G J
GJ
D000818:Animals; D002471:Cell Transformation, Neoplastic; D005260:Female; D007942:Leukemia, Experimental / Q000276:immunology / Q000503:physiopathology; D008550:Melatonin / Q000037:antagonists & inhibitors / Q000494:pharmacology* / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009271:Naltrexone / Q000494:pharmacology; D010870:Pineal Gland / Q000502:physiology* / Q000601:surgery; D016721:Radiation Leukemia Virus / Q000472:pathogenicity; D015996:Survival Rate
D009271:Naltrexone; D008550:Melatonin