Study On Analgesic Effect Of Active Component From Crude Cobra Venom In Wannan Area For Cancer Pain

Objective:Study on analgesic effect of active component（CVAF） from crude cobra venom inWannan Area for cancer pain.Methods:1. According to the lab’s past successful experience, the active component CVAF waspurified from crude venom of cobra using cation exchange chromatography andsize-exclusion chromatography. Select a clean male SD rats were40for the study of animals,as described with reference to Brigatte cancer pain model was constructed. Determination ofbasic pain threshold were randomly divided into4groups (n=10), normal control group (NCgroup), cancer pain model group (CP group), cancer pain model+CVAF group (CP+CVAFgroup), cancer pain models plus morphine (Morphine, MP) group (CP+MP group). Dailywere given at the same time point CP group were injected intraperitoneally (ip) saline1mL,CP+CVAF group were injected intraperitoneally (ip) equal volume of CVAF30μg/kg, CP+MP group were injected intraperitoneally (ip) equal volume of morphine5mg/kg,continuous injection for14days. Rats after administration of2h, using PL-200hot stingingmeter and BW-YLS-3E electronic tenderness at8am-12:00each rat was measured thermalpain threshold latency and mechanical pain threshold.2. Select a clean male SD rats were40for the study of animals, reference Brigatte cancerpain model was constructed. In accordance with the rats were randomly divided into4groups(n=10), normal control with high, medium and low-dose CVAF drug group. CVAF group (ip0.2ml), at doses of1.0mg/kg,0.3mg/kg and0.1mg/kg, the control group received anequal volume of PBS. Rats after intraperitoneal injection of different doses of the drug CVAF well tolerated and experimental four weeks before the experiment when the body weight ofrats survived to inspect; while rats were continuously observed8weeks activities, hair, feces,food and death situation. Line system in rats autopsy and histopathological detection, visualobservation of rat internal organs, the brain, heart, liver, spleen, kidney, lung histologicalsections were observed. After8weeks, the rats were still alive, each leaving one, notadministration, continue to observe two weeks after the line vivisection checked. Observe thecontents above.Results:.1.1) When the tumor cell suspension injected into CP group right foot toe male rats after6h rat subcutaneous right foot toe noticeable swelling, showed obvious limp, hold the foot,licking, and the emergence of appetite decreased piloerection, mild diarrhea and othersymptoms. Stimulating the right foot when rapid escape response. The NC bipedal rats noswelling, skin temperature higher anomalies.2) CP rats subcutaneous connective tissue edemaof the right toe area, see the large number of neutrophils, mononuclear cell infiltration; NCgroup showed no such changes.3) CP rats toes volume compared with NC group wassignificantly higher (P <0.01), the first three days reached a peak, then gradually reduced, butuntil14days toe volume was still higher than the normal control group.4) NC rats in thewhole body weight did not change significantly during the experiment, no significantdifference; CP group were injected with tumor cell suspension gradual weight; CP CVAF andCP MP rats, body weight also over time reducing the extension, but to reduce the magnitudeof the rats were less than CP.5) CP rats after injection of tumor cell suspension first daybegan to heat pain threshold decreased significantly, there are still continuing14days (P<0.05), suggested the presence of cancer pain thermal hyperalgesia in rats; cancer pain ratswere after intraperitoneal injection CVAF and MP TWL threshold right foot elevated (P<0.01); among CP MP TWL rats was significantly higher compared with the CP group (P<0.01), TWL increase over time to10days decreased slightly; CP CVAF TWL rats comparedwith the CP group threshold increases (P <0.05); and increase over time in the first eight days with CP MP group was no significant difference (P>0.05).6) CP rats after injection of tumorcell suspension first day mechanical pain threshold decreased significantly, there are stillcontinuing14days (P <0.05), suggested the presence of cancer pain in rats mechanicalhyperalgesia; cancer pain rats were after intraperitoneal injection CVAF and MP MWTthreshold right foot elevated (P <0.01); CP MP group than MWT increased significantlycompared to CP group (P <0.01), increased over time to10days MWT began to decline,suggesting that animals produce drug resistance; CP CVAF MWT rats compared with the CPgroup threshold increases (P <0.01); CVAF for cancer pain in rats affect the mechanical painthreshold was significantly hotter affect pain threshold and increase over time in the first7days with CP MP group showed no significant difference (P>0.05).2.1) Based on past successful experience in our laboratory has been successfullyisolated and purified cobra venom southern Anhui active ingredient CVAF. To CVAF drug,1.0mg/kg dose group in5min toxicity appears, followed by the performance of tachypnea,piloerection, reduced activity, further increasing the dose, can cause prostrate does not move,diarrhea, respiratory difficulties, spastic hindlimb paralysis, jumping, until death. The ratswere killed at10-30minutes, the other two groups did not die. Anatomy of death in ratsimmediately observe major organs and found breathing stops, the heart is still beating,macroscopic lung surface slightly pale, naked no obvious bleeding points, I found no visibleorgan pathological changes, the brain darling renal Insufficiency HE staining to observepathological changes. Histopathological lung alveolar capillary congestion interval, somealveolar exudate; darling spleen and brain biopsy light microscopy showed no bleeding andother abnormalities.2） Throughout the course of treatment (8weeks), with time graduallydecreased activity in rats, the incidence gradually vertical hair, the amount of food intake andbowel reduction also occurred. In experiments on rats survived and four weeks beginningweight for weighing, we can see the control rats at4weeks significantly reduce body weightoccurred; CVAF treatment group rats also occurred to reduce weight, then reduce the extentof its less than the control group, and CVAF (0.3mg/kg) group than alleviate CVAF (0.1mg/kg) group. After8weeks, the rats on the survival of the brain, heart, liver, spleen, lung and kidney OK histopathological observation shows that the brain, heart, liver, spleen, lung andkidney disease management sliced light microscope showed no bleeding and other exception.Recovery pathological condition observed through their identical with the control group.Conclusion:1. CVAF treatment time increases with increased cancer pain threshold in rats MWTTWL and does not produce tolerance and improved cancer pain and mechanical hyperalgesiain rats Thermal hyperalgesia, a good analgesic effect.2. High-dose lethal rats histopathological observation interval alveolar capillarycongestion, some alveolar exudate; brain, heart, liver, spleen, lung and kidney diseasemanagement sliced light microscope showed no bleeding and other abnormalities, suggestingCVAF with hemolysin different; long-term medication and restorative pathology investigationshows CVAF rat brain, heart, liver, spleen, lungs and kidneys had no significant effect, whichto some extent foreshadowed CVAF potential toxicity in rats little side effects.