Biological activity of a bombesin-like peptide extracted from the intestine of the ratfish, Hydrolagus colliei.
1. Ratfish (Hydrolagus colliei) intestines were boiled in water to inactivate proteases and then treated with cold 4% trifluoroacetic acid to extract bombesin-like peptides. 2. The extract was fractionated in several steps using reverse-phase and ion exchange HPLC, and bombesin-like immunoreactive peptides were detected by radioimmunoassay using an antiserum specific for the bioactive C-terminal region of bombesin. 3. A highly purified bombesin-like peptide-containing fraction stimulated amylase release in a dose-responsive fashion from rat pancreatic acini; the dose-response curve was parallel to a bombesin standard, and the ratfish peptide stimulated the same maximal rate of amylase secretion as the bombesin standard. 4. A potent, highly selective bombesin receptor antagonist completely abolished the stimulation of amylase release caused by the ratfish peptide, demonstrating the specificity of the response. 5. Estimates of the bombesin-like peptide concentration of this fraction by radioimmunoassay and by bioassay were nearly identical, indicating that ratfish bombesin is very similar biologically and antigenically to frog skin bombesin.
Thorndyke
M C
MC
Department of Biology, Royal Holloway and Bedford New College, University of London, Egham, Surrey, U.K.
Reeve
J R
JR
Vigna
S R
SR
D000681:Amylases / Q000378:metabolism; D000818:Animals; D001001:Anura; D001681:Biological Assay; D001839:Bombesin / Q000302:isolation & purification / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D005399:Fishes; D007422:Intestines / Q000737:chemistry*; D010179:Pancreas / Q000187:drug effects / Q000201:enzymology; D011863:Radioimmunoassay; D051381:Rats; D012867:Skin / Q000737:chemistry
D000681:Amylases; D001839:Bombesin