Study On Influence Of Chinese Cobra Venom To Inflammatory Cytokine Of Rat

Objective:This study was to establish rat model by intraperitoneal injection of Chinese cobra venom (CCV) and observe the mechanism of inflammation and acute myocardial injury by tumor necrosis factor alpha (TNF-a) and interleukin-6 (IL-6).Methods:Sixty health Sprague-Dawley (SD) rats fed for three days in Guangxi medical university experiment room were randomly (random number) divided into four groups, including the control group, one hour group, three hours group and six hours group after administration by intraperitoneal injection of CCV. The lyophilized CCV paired with saline solution 1mg/ml, and then CCV was injected to every experimental group, by a dose of 1.272mg/kg (dissolved by normal sodium). According to the above methods, the control group controlled with the same doses of normal sodium accordingly.(1) To investigate the performance of every group rats by continuous after injection.(2) According to the mentioned above methods, two milliliters abdominal aorta blood were collected to measure serum TNF-a and IL-6 in every experiment group after administration by intraperitoneal injection of CCV. The control group was collected the same dose of sample after one hour. Levels of TNF-a and IL-6 were determined by enzyme-linked immune-absorbent assay (ELISA), to study the inflammatory mechanism of cytokine caused by CCV.(3) After injection, every experiment group was sacrificed at every time point, the blocks of the myocardial tissue from the middle portion of the left ventricular free wall were collected and fixed in the 4% paraformaldehyde solution. Then the injection of the myocardial tissue was observed by light microscopy.(4) According to the mentioned above way, the changes of TNF-a and IL-6 in rat myocardial cells were observed with immunohistochemistry assay and the images were analysed.Results:(1) After administration by intraperitoneal injection of CCV, the symptoms of poisoning were markedly emerged in every expeiment group, but during the entire time, but there was no toxic manifestation in the control group.(2) One hour after injection of CCV, the levels of serum TNF-a rapidly increased, the markedly levels appeared 6-hour later injection; Significantly higher levels of serum IL-6 in the experiment groups as compared with the control group were shown on 3 hours group and 6 hours group but not on 1 hour group.(3) In every experiment group, the morphologic changes of myocardial tissue injection was obviously observed with light microscopy. These changes were significally shown on the 6 hours group but not on the 1 hour group,3 hours group and the control group.(4) Compared with the control group, we observed a great quantity of TNF-a and IL-6 positive cell among the myocardial cells of the rats, the average gray was decreased significantly on injecting CCV groups, there was much brown positive cell in the cytoplasm.Conclusion:(1) We successfully established rat model of snakebite by CCV and the symptoms of poisoning and morphologic changes of the myocardial tissue were observed after administration by intraperitoneal injection of CCV in rats.(2) CCV could increase the serum contents of TNF-a and IL-6 in rat and play an important role in the inflammatory mechanism.(3) TNF-a and IL-6 may play an important role in CCV induced acute myocardial injury in rats.