[Enzyme histochemistry: the effect of META-Li on Oncomelania hupensis].
OBJECTIVE
To explore the killing mechanism of META-Li against Oncomelania hupensis by observing the change of enzyme activity in snail tissue.


METHODS
Sixty snails were divided into 2 groups. Snails in experiment group were immersed in META-Li (100 mg/L) for 2d and soft tissue was separated for frozen sections. Histochemical staining for the enzymes CCO, LDH, SDH, AChE and NOS was done by routine method and the average grey density was measured under microscopy. Tissue sections of 10 snails were used to detect grey density for each enzyme. Snails without META-Li treatment served as control.


RESULTS
The enzyme activity of CCO and AChE in the experiment group was significantly lower than that in the control (t=12.26, P<0.01), that of LDH and NOS in the experiment group was significantly higher than that in the control (t=3.41, P<0.05). There was no significant difference on the enzyme activity of SDH between the two groups (t=0.51, P>0.05).


CONCLUSIONS
The snail-killing effect of META-Li may be relevant to the enzyme activity in energy metabolism and the blocking of the nerve transmission.
National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai 200025, China.
Dan
D
Zhu
Hong-jun
HJ
Li
He-xiang
HX
Liu
Yi
Y
Zhang
Jian
J
Guo
You-sheng
YS
Liang
Xiao-nong
XN
Zhou
D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D003576:Electron Transport Complex IV / Q000378:metabolism; D006651:Histocytochemistry; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008975:Molluscacides / Q000494:pharmacology*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D012908:Snails / Q000187:drug effects* / Q000201:enzymology*; D013385:Succinate Dehydrogenase / Q000378:metabolism
D008975:Molluscacides; D007770:L-Lactate Dehydrogenase; D019001:Nitric Oxide Synthase; D013385:Succinate Dehydrogenase; D003576:Electron Transport Complex IV; D000110:Acetylcholinesterase