Publication Abstract

HPLC and ELISA analyses of larval bile acids from Pacific and western brook lampreys

By S.S. Yun, A. P. Scott, J. M. Bayer, J. G. Seelye, D. Close and W. Li

Comparative studies have been performed on the two native North American lamprey species, the Pacific lamprey (Lampetra tridentata) and western brook lamprey (Lampetra richardsoni) found on the Pacific coast along with sea lamprey (Petromyzon marinus) from the Great Lakes to investigate bile acid production and release by larvae. HPLC analysis of gall bladders (and liver extracts) revealed that the major 3a-hydroxylated compound in the bile of both Pacific and western brook lamprey is the same as that previously identified in the bile of the sea lamprey - namely petromyzonol sulfate (PZS). The concentrations of PZS in gall bladders of sea lamprey, Pacific lamprey and western brook lamprey were 127, 146 and 277 µg/g fish, respectively. An immunoassay was developed for PZS (with a working range of 20 pg - 10 ng/well) and this confirmed the results of the HPLC analysis. The rates of release of PZS in the three species were measured using the immunoassay. They revealed that western brook and sea lamprey released PZS at a rate twenty times higher than in Pacific lamprey. Allocholic acid was detected only in the bile of the sea lamprey.

Reference:

S.S. Yun, A. P. Scott, J. M. Bayer, J. G. Seelye, D. Close and W. Li. 2003. HPLC and ELISA analyses of larval bile acids from Pacific and western brook lampreys. Steroids 68: 515-523