Abstract
This chapter focuses on the bradykinin (BK)-related peptides found in frog skin. The pathways of biosynthesis of BK-related peptides in frog skin are quite different from those in the blood and tissues of mammals. The kallikrein-kinin system of BK-related peptides synthesis in mammals involves the sequential action of several well characterized proteolytic enzymes. Alternative splicing of the primary transcript of the kininogen gene gives rise to a second mRNA that directs the synthesis of low-molecular mass kininogen. This protein is a substrate for glandular or tissue kallikrein, a serine-protease that is localized predominantly in the kidney, pancreas, and pituitary. Release of large amounts of BK, or a related peptide, into the lumen of the stomach of a predator will stimulate gastric and esophageal motility that may lead to activation of the vomiting reflex and ejection of the prey unharmed. The frog skin BK-related peptides show a wide range of potencies in eliciting contractile or relaxant responses in mammalian smooth muscle preparations, and peptides derived from probradykinins with weak antagonistic and BK-potentiating activities have also been identified.
Original language | English |
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Title of host publication | Handbook of Biologically Active Peptides |
Publisher | Elsevier Inc. |
Pages | 291-294 |
Number of pages | 4 |
ISBN (Print) | 9780123694423 |
DOIs | |
Publication status | Published (in print/issue) - 2006 |