ABSTRACT
Aim To establish two new rat models of visceral hypersensitivity in IBS by two chemical irritants.Methods Acetic acid or mustard was infused for six days in intestines of adult rats.After modeling,the rectal distention was performed and the thresholds of abdominal withdrawal reflex were measured.The frequency,peak value,peak-nadir value and area of the gastric and enteric electrical activity were recorded.And the contents of 5-HT in the blood serum were detected.Results Compared with the control group,the colon and rectum's sensitivity(P<0.05)and the frequency(P<0.01) of the acetic acid model were heightened.Meanwhile,the colon and rectum's sensitivity(P<0.01),the frequency(P<0.01),peak value(P<0.05),peak-nadir value(P<0.01)and area(P<0.01),and the contents of 5-HT(P<0.05)in serum of the mustard model were all changed,which indicated the increasing of sensitivity of the model.The colon and rectum's sensitivity,the gastric and enteric electrical activity and the contents of 5-HT in serum of the proving group were recovered to some extent.Conclusion The new rat model of visceral hypersensitivity in IBS is successfully set up by stimulating the intestines of adult rats with chemical substances.
ABSTRACT
Aim To establish diarrhea-predominant IBS SD rat model and appraise its intestinal tract.Method The postnatal rat of 8~21 days were given the successive stimulation of the inflammation inside the colon(rectum abouchement 0.087 mol?L-1 acetic acid 0.5 ml)to replicate the animal model of the IBS visceral hypersensitive.The change of IBS SD rat model organ sensitivity was studied,and the change of threshold of pain at ectocolon of model rat was observed,as well as the influence of excised intestinal canal systaltic motion with convulsion-induced agent for model rat.Results Model group was obviously lower than normal group with pressure threshold value of raise abdomen and extrados in the eighth week and the sixth week(P