盐酸普鲁卡因经皮离子导入的研究

目的：考察盐酸普鲁卡因的离子导入与电流强度、药物浓度的关系。方法：测定不同的电流强度、不同的药物浓度的离子导入增渗倍数（ＥＲ）。结果：固定药物浓度,电流强度为０．１,０．２和０．３ｍＡ时的ＥＲ值分别为６８．９９和１２７。固定电流强度０．２ｍＡ,药物浓度为０．０１５１,０．０３０４和０．０６０５ｇ／１００ｍｌ时的ＥＲ值分别为９５,９９和９８,结论：离子导入可以显著提高药物渗透速率,增渗倍数（ＥＲ）随     

Metabolic competence and susceptibility of intestinal epithelium to genotoxic injury during regeneration

The carcinogenic potency of many mutagens is increased in conditions of tissue regeneration. This involves fundamental changes of cellular division and differentiation, in intestinal epithelium. However, effects on epithelial capacity for carcinogen metabolism and susceptibility to genotoxic injury are unknown. Using a novel rat model, this study assessed expression of cytochrome P450 mono- oxygenases (Cyps), glutathione S-transferases (GSTs) and uridine diphosphoglucuronosyl transferase (UGT) in intestinal epithelium during sequential stages of regeneration. Enzyme induction and DNA adduct formation were also assessed after benzo[a]pyrene (BaP) exposure. Control assays were carried out in normal intestinal epithelium. Fewer phase I and II xenobiotic metabolizing enzymes were expressed in regenerating intestinal epithelium than in normal control intestinal epithelium (GSTA3, UGT in regeneration vs Cyp2B, GSTA1/2, GSTA4, GSTP1, UGT in control). Benzo[a]pyrene induced GSTA3 and UGT in regeneration vs Cyp1A, Cyp2B, GSTA1/2, GSTA3, GSTA4, GSTP1 and UGT in control normal intestinal epithelium. Benzo[a]pyrene induced low levels of GSTA3 in early regenerating intestinal epithelium but induction increased by >2- fold at late stage regeneration. Higher levels of benzo[a]pyrene 7,8- diol-9,10-epoxide (BPDE) DNA adducts were formed at early stages of regeneration, than at later stages. Intestinal epithelium displayed reduced metabolic competence and differential susceptibility to genotoxic injury from BaP, during regeneration.      

Preferential expression of the neuropeptide Y Y1 over the Y2 receptor subtype in cultured hippocampal neurones and cloning of the rat Y2 receptor

1. Neuropeptide Y (NPY) and NPY receptors are most abundant in the hippocampal formation where they modulate cognitive functions. Expression of NPY receptors in rat cultured primary hippocampal cells was investigated in the present study by use of combined molecular, pharmacological and immunohistochemical approaches, including the cloning of the rat Y₂ receptor described here for the first time.
2. More than 70% of the hippocampal neurones were endowed with [¹²⁵I]-[Leu³¹,Pro³⁴]PYY Y₁-like receptor silver grain accumulations and Y₁ receptor immunostaining. These radio- and immuno-labelling signals were distributed over cell bodies and processes of bipolar, stellate and pyramidal-like neuronal cells, as confirmed by neurone-specific enolase and MAP-2 staining.
3. Competition binding profiles revealed that specific [¹²⁵I]-[Leu³¹,Pro³⁴]PYY binding was competitively displaced according to a ligand selectivity pattern prototypical of the Y₁ receptor sub-type with [Leu³¹,Pro³⁴]substituted NPY/PYY analogues>>C-terminal fragments=pancreatic polypeptides, with the non-peptide antagonist BIBP3226 being most potent. This profile excludes the possible labelling by [¹²⁵I]-[Leu³¹,Pro³⁴]PYY of the newly cloned Y₄, Y₅ and Y₆ receptors.
4. The expression of the genuine Y₁ receptor was confirmed by RT–PCR in hippocampal cultures. In contrast, negligible levels of Y₂-like/[¹²⁵I]-PYY_3–36 binding were detected in these cultures in spite of the presence of its mRNA, as characterized by RT–PCR. The expression of both the Y₁ and the Y₂ receptor mRNAs was also noted in normal embryonic hippocampal tissues showing that signals expressed in cultured neurones were also present in utero.
5. Taken together, these results suggest that the Y₁ receptor subtype may be of critical importance in the normal functioning of the rat hippocampus, especially during brain development and maturation.

     

喙果绞股蓝中皂甙成分的研究

首次从喙果绞股蓝(Gymostemma yixingense CY Wu et SK Chen)中分得四个皂甙成分(Ⅰ～Ⅳ),经理化常数测定、光谱解析和化学方法确定了它们的结构。其中Ⅰ为新化合物,命名为喙果皂甙A(yixinosideA),Ⅱ,Ⅲ和Ⅳ分别鉴定为绞股蓝皂甙XLIVXLII(gypensideXLIV,XLII)和具明显调脂作用的人参皂甙Rb₁(ginsenosideRb₁)。此外,Ⅰ经酸水解得到一新皂甙元1β-羟基人参二醇(1β-hydroxylpanaxadiol)(Ⅴ)和一新次级甙,命名为喙果皂甙B(yixinosideB,VI)。     

呋喃二氢吡啶Ⅰ对离体兔心局部缺血的保护作用

呋喃二氢吡啶Ⅰ20μmol╱L能使离体兔心局部缺血心肌肌酸磷酸激酶(CPK)和α-羟丁酸脱氢酶(HBD)的释放量明显减少;冠脉阻力下降,流量增加;并能降低血浆及心肌中钙、钠含量,预防缺血性心律失常的发生。提示该药对离体兔心缺血心肌的保护作用,与降低缺血心肌细胞钙、钠含量有关。     

尼可地尔对缺血再灌注心肌线粒体功能的保护作用

近年来,许多资料表明,心肌缺血再灌注损伤与氧自由基有关,后者的主要细胞毒性反应是膜的脂质过氧化。尼可地尔(nicorandil,NICO)又名N-(2-羟乙基)硝酸烟酰胺,为烟酰胺与硝酸酯的结合物,是临床治疗心绞痛的新药。前文发现它对心肌缺血再灌注损伤有保护作用,其作用可能与抗脂质过氧化有关。本文用血液灌注离体兔心模型,观察缺血再灌注损伤时心肌线粒体呼吸功能的变化,及尼可地尔的保护作用。     

Neurotensin selectively antagonizes apomorphine-induced stereotyped climbing

In order to better characterize the neuroleptic properties of neurotensin, the dose-related effects of the peptide on stereotyped climbing, sniffing and licking induced by 0.6 mg/kg apomorphine were examined. The following doses of the peptide were injected intraventricularly 30 min prior to apomorphine administration: 0.9, 3.75, 30.0 and 60 micrograms. Results indicate that, whereas oro-facial stereotypies remained unaffected by the peptide, stereotyped climbing was significantly decreased with the two largest doses of neurotensin. These findings indicate that the profile of neurotensin's neurobehavioral effects is more akin to that of atypical than typical neuroleptics.     

Expression and functions of galectin-7 in ovarian cancer

There is a critical need to develop effective new strategies for diagnosis and treatment of ovarian cancer. In the present work, we investigated the expression of galectin-7 (gal-7) in epithelial ovarian cancer (EOC) cells and studied its functional relevance. Immunohistochemical analysis of gal-7 expression in tissue microarrays showed that while gal-7 was not detected in normal ovarian tissues, positive cytoplasmic staining of gal-7 was detected in epithelial cells in all EOC histological subtypes but was more frequent in high grade tumors and metastatic samples. Gal-7 expression correlated with a significant difference in the overall survival of patients with ovarian serous cystadenocarcinoma. Furthermore, using human EOC cell lines, we found that gal-7 expression was induced by mutant p53. Mechanistically, Matrigel invasion assays and live cell imaging showed that gal-7 increased the invasive behavior of ovarian cancer cells by inducing MMP-9 and increasing cell motility. EOC cells can also secrete gal-7. Recombinant human gal-7 kills Jurkat T cells and human peripheral T cells, suggesting that gal-7 also has immunosuppressive properties. Taken together, our study validates the clinical significance of gal-7 overexpression in ovarian cancer and provides a rationale for targeting gal-7 to improve the outcome of patients with this disease.     

苦参碱对脂多糖／痤疮丙酸杆菌诱导的小鼠肝炎及产生肿瘤坏死因子的影响

用小鼠致死性肝炎模型和ＴＮＦ体外诱生的方法，研究苦参碱（Ｍａｔ）对脂多糖（ｌｉｐｏｐｏｌｙｓａｃｃｈａｒｉｄｅｓ，ＬＰＳ）诱导的经痤疮丙酸杆菌（ｐｒｏｐｉｏｎｉｂａｃｔｅｒｉｔｔｍａｃｎｅｓ，ＰＡ）预刺激的小鼠产生肿瘤坏死因子（ＴＮＦ）以及致死性肝炎的影响。结果表明：Ｍａｔ（１０，５０ｍｇ·ｋｇ￣（－１），ｉｐ，ｂｉｄ×３ｄ）可降低血清ＴＮＦ和ＡＬＴ水平及小鼠对ＬＰＳ致死毒性的敏感性，并可在体外抑制ＬＰＳ诱导的经ＰＡ预刺激的小鼠腹腔巨噬细胞释放ＴＮＦ。提示Ｍａｔ的保肝作用与其抑制ＴＮＦ释放有关。     

Evaluation of the influence of chloroacetic acids on the pharmacokinetics of trihalomethanes in the rat

Chloroacetic acids (monochloroacetic acid [MCA], dichloroacetic acid [DCA], and trichloroacetic acid [TCA]) and trihalomethanes (THMs: chloroform [CHCl(3)], bromodichloromethane [BDCM], dibromochloromethane [DBCM], and bromoform [TBM]) are common by-products of the chlorination of drinking water. The purpose of this study was to evaluate the influence of chloroacetic acids on the pharmacokinetics of trihalomethanes in the male Sprague-Dawley rat. In the first series of studies, groups of 5 animals were given, by intravenous injections, a single dose of 0.125 mmol/kg of one of the four THMs. Additional groups received a binary mixture containing 0.125 mmol/kg of a THM plus 0.125 mmol/kg of a chloroacetic acid. The venous blood concentrations of unchanged THMs were measured by headspace gas chromatography from 5 min to 6 h postadministration. The areas under the blood concentration versus time curves (AUCs) of CHCl(3), BDCM, and DBCM were increased by a factor of 3.5, 1.6, and 2, respectively, by coadministration of TCA. DCA coadministration resulted in an increase in the AUC of DBCM (x2.5) and TBM (x1.3), whereas MCA modified the Cmax (x1.5) and AUC (x1.8) of BDCM and the AUC of DBCM (x2.5). In the second series of experiments, animals received either a single dose of 0.03125 mmol/kg of one of the four THMs, a mixture containing 0.03125 mmol/kg of each of the four THMs (total dose = 0.125 mmol/kg), or a mixture containing 0.03125 mmol/kg of each of the four THMs plus 0.125 mmol/kg of either TCA or DCA. Results indicated that the AUCs of CHCl(3), BDCM, DBCM, and TBM were increased during coadministration compared to single administrations (+2.5-fold). Combined administration of the four THMs with TCA, and not DCA, resulted in an increase of the AUCs of THMs (CHCl(3): x11.7; BDCM, DBCM, and TBM: x3.9) and an increase in the Cmax of CHCl(3) (x1.9). Overall, these results indicate that, at the dose levels tested in this study, TCA alters the blood concentration profiles of THMs.