Efeitos da administração de diferentes concentrações de folhas de Ipomoea asarifolia na ração de camundongos e eliminação da toxina tremorgênica pelo leite.

Abstract

Ipomoea asarifolia is a tremorgenic plant whose active principle is not yet determined and the main clinical signs observed in the poisoning this plant in ruminants are intention tremors and incoordination. The aim of this study was to see if I. asarifolia is tremorgenic for mice and its effect on balance, coordination and muscle strength and demonstrate if the tremorgenic toxin is excreted by milk. In the first study, three groups of adult male mice of the Swiss strain received ration containing 0, 20% and 30% of the leaves of I. asarifolia for 30 days. On day 0 and every five days were measured feed and water intake and the weight of the animals and performed tests on the elevated bar, wire suspension and rota rod. Changes in balance and motor coordination observed in the elevated bar and the rota rod suggest that the plant affects the central nervous system. The intoxication was evident by the significant reduction in water consumption and weight of the animals and the mortality in experimental groups. However, muscle tremors were not observed, which does not justified the use of adult male mice to study the toxic compound of I. asarifolia. To demonstrate whether tremorgenic toxin of the I. asarifolia is excreted by milk, three groups of Swiss female mice received, immediately after given birth until weaning, ration containing 0, 20% and 30% of dry I. asarifolia. All the offsprings of the females that received I. asarifolia showed tremors 2-4 days after birth. The offsprings of the females that received 20% I. asariflia recovered 4-7 days after weaning. The offsprings of the females that received 30% of the plant in the ration died with tremors before weaning or until two days after weaning. It is concluded that the tremorgenic compound of I. asarifolia is eliminated by milk and that lactating mice may be used for the determination of the toxic compound of this plant.