Purification and characterization of a novel antinociceptive peptide from venom of Agkistrodon halys Pallas

Abstract

Venom of Agkistrodon halys Pallas can control severe pain such as cancer pain and neuropathic pain, but it is made up of complicated components. Aim of this study is to separate major analgesic fraction from venom of A. halys Pallas, and to reveal its biochemical and pharmacological properties. Three steps with ion exchange column first and molecular sieve columns next were used to separate and purify the fractions of venom. Analgesic effects were evaluated by hot plate tests and writhing tests in mice. The molecular weight (MW), isoelectric point, amino acid sequence, purity were respectively determined by SDS-PAGE electrophoresis, isoelectric focusing, Edman degradation and HPLC. The dependence and tolerance were observed by withdrawal test in rats, and analgesic effects were observed in mice during 7 days administration. Fourteen fractions were obtained by separation; the best analgesic fraction named Pallanalgesin was selected by ED50 and LD50. It had single band in electrophoresis, relative purity 92.16 %, MW 16.6 kDa, isoelectric point 8.8, and former sequence of ten amino acids H-L-L-Q-F-R-K-M-I-K. It showed significant analgesic effect without tolerance and dependence. As a novel analgesic, Pallanalgesin has been found to explain the function of venom of A. halys Pallas on severe pain control in traditional uses.