Purification and biological activity of alligator bradykinin

S. Comeau, V. A. Lance, J. W. Hicks, J. M. Conlon

Research output: Contribution to journalArticlepeer-review

28 Citations (Scopus)


Incubation of plasma from the alligator (Alligator mississipiensis) with glass beads in the presence of a kininase inhibitor resulted in the activation of the kallikrein-kinin system and generation of bradykinin-like immunoreactivity. The kinin peptides were purified to homogeneity and were shown to comprise [Thr6]-bradykinin and des-Arg9[Thr6]bradykinin in the molar ratio of ~10:1. Bolus injections of synthetic [Thr6]bradykinin into the jugular vein of the anesthetized alligator resulted in a dose-dependent decrease in mean arterial blood pressure. The minimum dose of kinin producing a significant fall in pressure was 0.07 μg/kg body wt and the maximum response (25 ± 6% fall; mean ± SD, n = 8) was produced by a dose of 0.56 μg/kg body wt. The dose producing a half-maximum response was 0.19 ± 0.08 μg/kg. The data indicate that alligator plasma contains all the components of the kallikrein-kinin system found in mammals and suggest that the system may be of physiological importance in the regulation of cardiovascular function in these reptiles.

Original languageEnglish
Pages (from-to)R400-R404
JournalAmerican Journal of Physiology - Regulatory Integrative and Comparative Physiology
Issue number2 32-2
Publication statusPublished (in print/issue) - 1992


  • crocodilian
  • high-performance liquid chromatography
  • kallikrein
  • kininogen
  • turtle
  • vasodilator activity
  • [Thr]bradykinin


Dive into the research topics of 'Purification and biological activity of alligator bradykinin'. Together they form a unique fingerprint.

Cite this