Metacercaria excystment

A number of reports have suggested a relationship between cysteine protease activity and excystment of metacercariae. Cysteine proteases may act alone or in concert with extrinsic host factors such as trypsin in the host gut (Intapan and Maleewong, 2001 Li et al., 2004). In vitro, Paragonimus ohirai metacercarial cysteine protease activity is induced by addition of the bile salt, sodium cholate and parasite... 

Ikeda, T. (2003) Involvement of cysteine proteinases in excystment of Paragonimus ohirai metacercariae induced by sodium cholate and A23187. Journal of Helminthology 77, 21-26. 

Intapan, P. and Maleewong, W. (2001) In vitro excystation of Paragonimus heterotremus metacercariae. Journal of Parasitology 87, 1184-1186. 

IMPORTANCE TO INTESTINAL PARASITES Bile is of particular importance to intestinal parasites, for in many cases it is involved in the trigger mechanisms concerned in the hatching of helminth eggs, excystation of protozoan cysts, evagination of cestode scoleces and excystment of trematode metacercaria. In relation to cestodes, its role in... 

Schneck, J.L. Fried, B. Sherma, J. Effects of tonicity on the release of neutral lipids in Echinostoma caproni adults and observations on lipids in excysted metacercariae. Parasitol. Res. 2004, 92 (4), 285-288. 

Ponder, E.L. Fried, B. Sherma, J. Thin layer chromatographic analysis of free pool amino acids in cercariae, rediae, encysted metacercariae, and excysted metacercariae of Echinostoma caproni. J. Liq. Chromatogr. Relat. Technol. 2003, 26 (16), 2697-2702. 

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