Abstract: This paper reports the studies on isoenzyms of lactic dehydrogenase (LDH),esterase (FAST) and acid phosphatsse(AP) in cyst fluid,hydatid cysts,protoscoleces and cyst walls of alveolar hydatid (metacestoda of Echnococcus multilocularis)by PAGE analyses.In LDH isoenzyme analysis only 4 enzymatic bands revealed in each specimen of cyst fluid and hy-datid cyst.In EST isoenzyme analysis 14,17,3 and 13 enzymaic bands were found in speci-mens of hydatid cysts,cyst fluid,protoscoleces and cyst walls respectively;while enzymatic bands of AP were 4,2,1 and 1 correspondingly in four specimens.The result of tests showed that in specimens of cyst fluid the number of enzymatic bands in three isoenzymes were more than that in other specimens and they were stained more strongly,so cyst fluid might play an improtsnt role in the metablism of alveolar hydatid.

Key words: alveolar hydatid, PAGE, isenzyme, LDH, EST, AP