Changes And Significance Of Glutamate Receptors And Related Proteins In Chronic Pancreatitis Rats

ObjectiveChronic pancreatitis(CP)is a common disease of the pancreas,there is an upward trend in the incidence of CP according to the epidemiological investigation.The most frustrating and challenging aspect of caring for CP patients is pain management.analgesic measures based on the exisiting mechanisms of pain in CP are often not satisfactory to the patients,it has great clinical value for finding new mechanism and treatment of pain in CP.It is reported that the central nervous system involved in the formation of the chronic pain.Under the action of outside stimulation for a long time,it can make the central nervous system's response to pain.Anterior cingnlate cortex(ACC)plays a critical role in the modulation of visceral pain response in visceral hypersensitive rats,and the process is mediated by enhanced activity of glutamate receptor,glutamate receptors are widely distributed in ACC,LTP was found in a variety of diseases with pain.It is recognized that the structure and function of visceral pain pathway are changed in CP patients with pain.In the current study,we are investigating the changes of glutamate receptors and related proteins in ACC of CP rats with chronic abdominal pain and exploring the mechanism of pain.Method(1)CP rat model is established by injecting dibutyltin dichloride(DBTC)through tail vein.The rats are injected with ethanol and glycerol mixture through tail vein in control group.After 4 weeks of injection,the rats are tested for mechanical pain.(2)The protein expression of glutamate receptor NR2 A,NR2B,GluR1 and related protein NSF and PICK1 in ACC of rats are detected by Western blot,respectively.(3)The mRNA expression of NR2 A,NR2B,GluR1,NSF and PICK1 in ACC of rats are detected by RT-PCR,respectively.Results(1)DBTC injected through tail vein in rat can establish the CP rat model,We can find that,acinar atrophy significant,pancreatic ductal distortion,inflammatory infiltration,and periductular and intralobular fibrosis,stromal proliferationobvious through Hematoxylin and eosin staining.In the control and na?ve rats,the pancreas presented a normal appearance.(2)Von Frey hair was used to test the mechanical pain,We observed that CP rats showed persistent mechanical hypersensitivity in the abdomen compared to either naive or to control rats.(3)Western-Blot and RT-PCR in CP rats model found that glutamate receptor NR2 A,NR2B expression were statistically increased in ACC(P<0.05)compared with that of control or naive group,GluR1 and NSF,PICK1 changes were had no significant statistically.Conclusion:DBTC was injected with rat through tail vein can make the CP rat model with abdominal pain successfully,the CP rat model ' glutamate receptor NR2 A,NR2B were significantly increased in ACC,may be involved in the formation of pain in CP.which means glutamate receptor might play an role in modulation of pain in CP.