Tiger Analgesic Peptide - I (hwap-i), Analgesic Activity And Toxicity Of Study

The huwena analgesia peptide-I ( HWAP-I ) is a neurotoxic peptide with the analgesic activity isolated from the crude venom of Chinese bird spider Selenacosmia huwena . HWAP-I is a N-type calcium ion channel blocker, which can effect the release of neurotransmi tter from the nerve ending of cholinergic and the adrenergic synapse .1. The studies of analgesic activity of HWAP-I given through three different administration methods in conscious rats by subcutaneous inject ion of formal in into surface of hindpaw. The results indicated epidural space administration is the best way for HWAP-I to give analgesic effect. The other two administration methods are proved to have less analgesic effect.2. The studies, of analgesia activity of HWAP-I in rats by subcutaneous injection of bee venom into surface of hindpaw . The results indicated that the hyperalgesia caused by bee venom injection were alleviated by HWAP-I from the dose of 10 g/kg, 25 g/kg, 50 g/kg to 75 g/kg compared to nature saline and the latency of thermal stimulus in injection area was significantly increased(p<0. 05). The dose-effect curve figurs indicated that ED50 of analgesic effect of HWAP-I was approximately 30 g/kg in the rats of subcutaneous bee venom into surface hindpaw.3. To investigate the acute toxicity of HWAP-I given by intrathecal injection(i. t.), a serial doses of HWAP-I was given in conscious rats. The LD50 of HWAP-I is approximately14. 8 g/kg (i. t.). Nature saline had been used as control group. At the same time , the same tests were done to SNX-III and the results indicated that LD50 of SNX-III (i. t.) is approximately 200 g/kg. The results indicated that SNX-III will be safer than HWAP-I in the clinic.4. To investigate the chronic toxicity of HWAP-I given through epidural space, the rats were given HWAP-I for three months or two months other day at different doses. It's 100 g/kg, 50 g/kg, 25 g/kg respectively. Half of the rats were killed to do blood example analysis and pathological tests After given HWAP-I for three months and the another half of rats were ki 1 led after given HWAP-I for two months and stopped giving HWAP-I for another 14 days . All the results indicated that all kinds of tissues and organs in rats given HWAP-I for three months have no evident toxicity effect.