TOXICOLOGICAL STUDIES ON THE LEAVES OF AVICENNIA-MARINA (MANGROVE) INRATS

Haematological, biochemical and pathological effects in rats produced by the salt-tolerant plant Avicennia marina given at oral doses of 1 o r 4 g kg(-1) for three consecutive days or 0.5 g kg(-1) day(-1) for 28 consecutive days are reported, No overt behavioral changes, moribundi ty or mortality were seen in either of the two experiments, A dose of Ig kg(-1) did not affect significantly either body or liver weights, H owever, at a dose of 4 g kg(-1) the extract reduced both body and live r weights, The extract at both doses significantly increased leucocyte (mainly neutrophil) counts but did not affect significantly erythrocy te counts, haemoglobin concentration or the haematocrit, Except for a slight, but statistically significant, decrease in plasma glucose conc entration and an increase in Na, Ca, Cu, Mg and cholesterol concentrat ions and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities, the extract exerted no significant effects on plasm a biochemistry, The treatment produced dose-related mild cellular dege neration in the liver and congestion in the central veins, There were also prominent Kupffer's cells and monocellular infiltrations, In the kidneys there was shrinkage and cellular degeneration of glomeruli and patches of medullary haemorrhage, In the spleen a slight activation o f the germinal centre in the white pulp was noted, Subchronic treatmen t with the extract did not affect significantly the body and liver wei ghts, the water intake, faecal and urinary output, leucocyte and eryth rocyte counts, haemoglobin or haematocrit, There was a significant dec rease in the number of platelets and an increase in the number of neut rophils, No significant changes in plasma biochemistry were observed, except for a 15% increase in AST activity, Subchronic treatment produc ed a significant reduction in glutathione concentration, amounting to about 20%, Histopathological findings after the subchronic treatment w ere similar in nature but milder than those seen after the acute treat ment, (C) 1998 John Wiley & Sons, Ltd.