Apoptosis Of Interstitial Cells Of Cajal In Rat With Yangming Fu-organ Diseases And Effect Of Da-Cheng-Qi Decoction

Yangming fu-organ disease(YMFOD) is common clinical syndrome ofgastrointestinal motility disorders, which charatcterred by abdominal mass, fullness,dryness, distension of excess type. Recently, it reported that the interstitial cells of Cajal(ICC) in gastrointestinal tract were closely linked to gastrointestinal smooth musclespontaneous contractile activity, and played important role in gastrointestinal motility,which was very important to digestion and absorption function．Objective:This study aimed at evaluating apoptosis of ICC in rat with Yangmingfu-organ disease, and the therapeutic effect of Da-Cheng-Qi decoction (DCQD).Methods: One hundred Wistar rats of weighing180-220grams were randomlydivided into control group (20rats), Yangming fu-organ disease group(YMFODgroup)(40rats), and Da-Cheng-Qi decoction treat group(DCQD group)(40rats). Therats in YMFOD group were fed Chinese “hot medicine” which included prepareddaughter root of common monkshood, cassia bark, and dried ginger for12consecutivedays. In the13th-14th day the rats were fed their own feces suspension,15th dayintraperitoneal injection of bacterial endotoxin was taked. And the animal model ofYMFOD was established. Instead, the rats in control group were injected with the samevolume normal saline, and the rats in DCQD group were fed DCQD after the model ofYMFOD were established for5days. The proximal small intestine was taken in eachgroup and studied at20th. Apoptosis was evaluated by histochemical staining methodand terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)method. The ICC morphologic change was observed by transmission electronmicroscopy.Results: Anatomy description showed that compared with control group, theintestine of rats with YMFOD were significantly swelling, and many bleeding points was appeared in the mesenteric. After treated with DCQD, the symptom of swelling andbleeding points was significantly alleviated.Under light microscopy it was showed in control group that the small intestinalmucosa layer was neat, and these cell’s structure was clear. Submucosa glands appearednormal. Smooth muscle layer distribute uniform, there were more nucleus appeared incontrol group. In YMFOD group it were found that small intestine villi was less and flat,thinning mucous with loose connections between cells. Submucosa structural wasdisorder. Smooth muscle layer was meager. More inflammational cells were infiltratedamong either layer of intestinal gut wall. Compare with YMFOD group, the damagewas reduced in DCQD group. Only a small amount of lymphocytic was infiltrated.Apoptosis was detected by the TUNEL method. In control group, no cell waslabeled by TUNEL method on whole-mount preparations in the intestinal wall. The ICCcellular networks were incomplete in the YMFOD group, a number of Kit+/TUNEL+double-positive cells appeared，and a number of apoptotic ICC were observed. In theDCQD group, the ICC cellular networks seemed to be intact; however, still fewer ofKit+/TUNEL+double-positive cells were observed, which located within the ICC andhad identical features with normal ones.The proximal small intestine was taken in each group for transmission electronmicroscopic examination. In the control group the ICC rendered as large nucleus lesscytoplasm; oval nucleus, chromatin distributed around the nucleus; mitochondria,smooth endoplasmic reticulum and Golgi bodies were abundant, fewer thick filaments,intermediate filaments distributed in the cell processes and perinuclear. Between ICCand smooth muscle cell there were many gap junctions. The membrane of ICC inYMFOD group was intact, the pits around the membrane were reduced. The cell wasirregular. Gap junction between ICC and intestinal smooth muscle cell was decreased,the distance with the surrounding cells was increased; cytoplasmic electron density wasuneven, mitochondrial swelling, smooth and rough endoplasmic reticulum were reduced,Golgi apparatus decreased, nuclear lamina widened, and the uneven electron wasdistributied nucleus. In DCQD group there was no obviously edema mitochondrion inICC. The membrane of ICC was integrity. There were rich smooth endoplasmicreticulum. There were many meture Golgi apparatus and abundant intermediatefilaments. There was no significant increase in nuclear lamina, and chromatinmargination was obvious.Conclusion The result of this study showed that in YMFOD group a number of Kit+were lost, there was severe morphologic and functional damage of ICC inYMFOD, and DCQD could repaire the damage and promote the function of ICC. Allresult indicated that in YMFOD group the intestinal could lead to apoptosis of ICCwhich may contribute to the gastrointestinal motility disorders, and DCQD involved inrecovery of ICC.