Effects Of Cadmium, Lead And Copper On Cellular Ultrastructure And Esterase Isoenzyme Of Freshwater Crab, Sinopotamon Yangtsekiense

Section one: EFFECTS OF CADMIUM ON ULTRASTRUCTURE OF MUSCULAR CELLS IN SINOPOTAMON YANGTSEKIENSEMuscle is a very important tissue of the (Sinopotamon yangtsekiense). In this experiment, by methods of transmission electron microscopy, effects of low dosage of Cd2+ (1.87mg/L) on the ultrastructure of muscular cells in male crabs at the different times were studied from September to November in 2001.In the experiment,male crabs were bought from aquatic product market in Taiyuan and raised in laboratory for more a weed before treatment. The mature medium size male crabs were chosen and divided into two groups. One group was raised in dechlorinated water and the other group was raised in low dosage of Cd2+. Water was changed in every two days and the crabs were fed with fish meat. The treated and control animals were dissected at different times(5d,15d,30d).The results showed that the muscle ultrastrucrure was damaged by cadmium. The ultrastructure change increased with time of cadmium treatment. The damage was mainly in the mitochondria, nucleus and myofibril. The mitochondria expanded and vacuolated and its cristae disappeared; the double membrane was broken. The nucleus were disorganized, some of them changed greatly in morphology. At the end of the experiment some nucleus decomposed eventually. In the experiments the myofibril was damaged very lightly, at the end of experiment some myofibril were broken. But the damage of the myofibril is lightly than cuclear and mitochondria. The cause of it maybe is that muscle is protect by the heavy carapace and myofibril is not a main object tissue of the cadmium.The result showed that muscle cells is damaged by exposure in low dosage of Cd2+. So cadmiun is a very important poison substance in the environment.Section two: EFFECTS OF LEAD ON ULTRASTRUCTURE OF MYOCARDIAL CELL IN FRESHWATER CRAB SINPOTAMON YANGTSEKIENSEFrom May to June in 2002, the effect of Pb2+ on ultrastructure of myocardial cells of Sinopotamon yangtsekiense was studied by using transmission electron microscopy(TEM). The results showed that the ultrastrucrure of myocardial cells was abnormal at the 10th day. The longer the time, the more serious damage on the cell was. Most ones were these disorganized partly, mainly, till all, mitochondria fused by itself, circled, mitochondria membrane broke and disintegrated. In addition, chromatin discomposed, apoptic body appeared, nuclei envelope broke and nuclei matrix spilled out. Meanwhile myofibril dark band disappeared and bright band broke. At last, the mechanism of Pb~ toxicity is explored.Section three: EFFECTS OF CADMIUM AND COPPER ON ESTERASE ISOENZYME OF FRESHWATER CRAB, SINOPOTAMON YANGTSEKIENSEThis paper dealed with the effects at different dosages Cd2+ and Pb2+ on the esteraseisoenzyme EST of the gill, hepatopancreas and spermary by using polyacrylamide gel electrophoresis (PAGE). The results showed that the effects cadmium and copper on esterase isoenzyme activity are not only the activation but the inhibit as well. There were different effects of Cd2+ and Pb2+ on EST isoenzyme of the major tissues. After treatment 7 days, specificity isozyme patterns is not exist in hepatopancreas's isozyme patterns, the dominance isozyme patterns is at 0.59 and 0.77 of Rf value. Isozyme patterns of the gill is difference from the hepatopancreas, They had two steady identical basic isozyme bands at 0.34 and 0.76 of Rf value, but the activation is changed. The Isozyme patterns of spermary and heart is same to hepatopancreas, not show a specificity dominance isozyme patterns, spermary exist dominance isozyme patterns at 0.29 of Rf value, the heart exist dominance isozyme patterns at 0.32 of Rf value.At different dosages of Cd2+ and Cu2+ , there was dosage domino effect for the EST isoenzyme of one tissue.Section four: EFFECTS OF COPPER AND CADMIUM ON ULTRASTRUCTURE OFMYOCARDIAL CELL IN SINOPOTAMON YANGTSEKIENSEThe effect of copper and cadmium on ultrastructure of myocardial cells of Sinopotamon yangtsekiense was studied by us...