Expressions of PCNA,p53,p21^(WAF-1)and cell proliferation in fetal esophageal epithelia:Comparative study with adult esophageal lesions from subjects at high-incidence area for esophageal cancer in Henan,North China

AIM: To characterize the expression of p53, p21WAF-1 and proliferation-cell-nuclear-antigen (PCNA) in fetal esophageal epithelia and to determine the role of these genes in proliferation of fetal and adult esophageal epithelial cells. METHODS: Immunohistochemical avdin-biotin peroxidase complex (ABC) method was applied to 31 cases of fetal esophageal specimens and 194 cases of adult esophageal specimens to detect the expression of p53, p21WAF-1 and PCNA in fetal and adult esophageal epithelia. RESISTS: Both the PCNA positive immunostaining cell number and PCNA positive immunostaining rate in fetal esophageal epithelia (5064-239) were significantly higher than those in adults, induding normal epithelia (2004-113) and epithelia with basal cell hyperplasia (BCH) (2864-150) (P<0.05, ttest). However, the number of PCNA positive immunostaining cells in adult esophageal dysplasia (7194-389) and squamous cell cardnoma (SCC) (12614-545) was apparently higher than that in fetal esophageal epithelia (5064-239) (P<0.05, tbest). The positive immunostaining rabe of P53 was 10 % (3/31) in fetal esophageal epithelia, which was significantly lower than that in adult normal esophageal epithelia (50 %), adult epithelia with basal cell hyperplasia (62 %), dysplasia (73 %) and squamous cell carcinoma (86 %) (P<0.05, Fisher''s exact test). No p21WAF-l positive immunostaining cells were observed in fetal esophageal epithelia. However, p21w^l positive immunost^ining cells wereobserved in adult esophagus with 39 % (11/28) in normal, 38% (14/37) in BCH, 27 % (3/11) in DYS and 14 % (1/7) in SCC. CONCLUSION: PCNA could act as an indicator accurately reflecting the high proliferation status of fetal esophageal epithelium, p53 may play an important role in growth and differentiation of fetal esophageal epithelium, p21WAF-1 may have no physiological function in development of fetal esophageal epithelium.

Effect of tetramethylpyrazine on exocrine pancreatic and bile secretion

AIM: To investigate the effect of tetramethylpyrazine (ligustrazine, TMP) on the secretion of exocrine pancreas (and biliary).METHODS: In in vivo study, we investigated the effect of TMP on the secretion of pancreatic-bile juice (PBJ) in rats.Using human pancreatic duct cell line, CAPAN-1, combined with the short-circuit current (ISC) technique we further studied the effect of TMP on the pancreatic anion secretion.RESULTS: Administration of TMP (80 mg/kg, ip) significantly increased the secretion of PBJ (P<0.05), but the pH of PBJ and the secretion of pancreatic protein were not significantly affected. Basolateral addition of TMP produced a dosedependent increase in ISC(EC50=1.56 mmol/L), which contained a fast transient ISC response followed by a slow decay. Apical application of Cl- channel blockers, DPC (1 mmol/L),decreased the response by about 67.1% (P<0.001), whereas amiloride (100 μmol/L), a epithelial sodium channel blockers,had no effect. Removal of extracellular HCO3- abolished TMP-induced increase in ISC by about 74.4 % (P<0.001),but the removal of external Cl- did not. Pretreatment with phosphodiesterase inhibitor, TBMX(0.5 mmol/L), decreased the TMP-induced ISC by 91% (P<0.001).CONCLUSION: TMP could stimulate the secretion of PBJ,especially pancreatic ductal HCO3- secretion via cAvlp or cGMP-dependent pathway. It need further study to investigate the roles of cAMP or cGMP in the effect of TMP on the secretion of exocrine pancreas.

Increased expression of α-synuclein in different age APP transgenic mice model of Alzheimer＇ s disease and intervention by Chinese components

AIM To investigate the expression change of α-synuclein in the brain of different age AD-like an-imal model and to explore the pathology mechanism of α-synuclein in neural degeneration and protective effect of 2 kinds of Chinese components. METHODS A generally accepted animal model of Alzheimer' s disease-APP V717I transgenic (Tg) mouse was observed from 4 to 16 month old. The Tg mice wererandomly divided into model group(4 month, 10 month and 16 month old), Shen-wu capsule with the dose of 0.4g and 1.2g/kg/d, 2,3,5,4’-tetrahydroxystilbene-2-O-β-D-glucoside(TSG), one of effective components in Polygonum muhiflorum, at dose of 0. 05,0.1 and 0.2g/kg/d.