RESUMEN
The present work was carried out to investigate the effect of leucine on the biological activity of hypoglycin A. Leucine-free hypoglycin A, prepared from the ackee (Blighia sapida) seeds, has been shown to cause inhibition of the growth of broad bean radicles. When supplied simultaneously, leucine had no effect on the degree of inhibition produced by hypoglycin A even when the leucine concentration was four times that of hypoglycin A. Although the acceped structure of hypoglycin A bears a relationship to that of leucine, yet leucine does not antagonise the inhibitory action of hypoglycin A. When injected intraperitoneally into rats, fasted for 48 hours to ensure complete depletion of their liver glycogen, hypoglycin A induced hypoglycemia. This hypoglycemia was potentiated by leucine when administered one hour before hypoglycin A. These findings indicate that the hypooglycemia induced by hypoglycin A is not a result of the exhaustion of the liver glycogen as was suggested by Patrick (1954). They also indicate that the liver is not the principal site of action as thought by Chen et al. (1957).(AU)
Asunto(s)
21003 , Ratas , Hipoglicinas/efectos adversos , Leucina/administración & dosificación , Hipoglucemia , Glucógeno Hepático , BlighiaRESUMEN
Crude and purified extracts from M. charantia plants were tested for their anti-growth properties on a variety of biological materials. These extracts inhibited the germination of maize, cotton and broad bean seeds, as well as the formation of adventitious roots on Bryophyllum leaves. The neutralized acidic fraction also inhibited the division of sea urchin eggs and foetal development in rats, caused a slight increase of the life expectancy of mice bearing tumours of Sarcoma 180, and suppressed the growth of Her2 cells in tissue culture. Oral administration of the crude whole plant extract to a lymphatic leukaemic patient caused a marked increase in the haemoglobin content of teh blood and a noticeable decrease in the white bloob cells. When the crude extract was fractionated on resin columns and then on chromatographic paper, a yellow material was separated and analysed for its elemental constituents. Where tested, it proved to be a more potent growth inhibitor than the whole plant extract or other fractions thereof (AU)