Effect of L-dihydroxyphenylalanine (L-dopa) and methionine on tissue S-adenosylmethionine concentrations in cobalamin-inactivated fruit bats.
The fruit bat Rousettus aegyptiacus develops cobalamin deficiency when exposed to the gas nitrous oxide (N2O). The effect of dietary methionine (600 mg/kg fruit) or L-3, 4-dihydroxyphenylalanine (L-dopa, 100 mg/kg body weight daily) on brain and liver S-adenosylmethionine (AdoMet) concentrations, and on the neurological impairment was studied. Methionine supplementation significantly delayed the onset of neurological impairment (p less than 0.01) and resulted in a 2.4 fold increase in liver AdoMet levels. Brain AdoMet levels were unchanged. L-dopa, which is methylated by means of AdoMet did not aggravate the N2O-induced neuropathy but did lower, albeit insignificantly, brain AdoMet levels. The results do not support the hypothesis that the neurological impairment and death in cobalamin inactivated bats is a result of a depletion of methionine or AdoMet in the nervous system.
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D002685:Chiroptera / Q000378:metabolism*; D007980:Levodopa / Q000494:pharmacology*; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008715:Methionine / Q000494:pharmacology*; D009420:Nervous System / Q000503:physiopathology; D009609:Nitrous Oxide; D012436:S-Adenosylmethionine / Q000378:metabolism*; D014806:Vitamin B 12 Deficiency / Q000139:chemically induced / Q000378:metabolism* / Q000503:physiopathology
D007980:Levodopa; D012436:S-Adenosylmethionine; D008715:Methionine; D009609:Nitrous Oxide