白三烯受体拮抗剂对哮喘的治疗作用

白三烯是哮喘过程中的重要炎性介质之一，可在哮喘的多个环节上发挥作用，通过与其特异性受体结合诱发哮喘，因此，阻断白三烯与其受体结合就成为抑制哮喘发作的新途径．针对白三烯在哮喘中的作用机制及应用白三烯受体拮抗剂治疗作一综述．     

P物质对GABAA受体介导电流的作用

应用全细胞膜片箝技术,在大鼠新鲜分离的背根神经节细胞上观察到:SP对GABA激活电流有调制作用。实验结果表明:多数受检的大鼠背根神经节神经元对SP(28/41,68.5％)和GABA(36/41,88.2％)敏感,100μmol/LSP和100μmol/L GABA激活内向电流的幅值分别为243.8±82.7pA(x±s,n=9)和1.76±0.48nA(x±s,n=13)。GABA与SP激活的内向电流明显不同,前者具有明显的去敏感现象。实验预加SP(0.001～1μmol/L)30s后再加GABA,则GABA激活电流的幅值明显减小,而且GABA激活电流减小的程度与预加SP的浓度呈量效依赖关系。SP主要抑制GABA激活电流的峰电流,对其稳态电流的抑制不明显。预加0.1μmol/L SP之后约4min左右,SP对GA-BA激活电流的抑制效率最大,为49.8±7.2％(x±s,n=7,P≤0.01),而预加SP 12min之后,SP才失去对GABA激活电流的抑制作用。     

Differential effects of the serotonin receptors on cultured rat cerebral cortical neurons

Effects of serotonin (5-HT) on cerebral cortical neurons were examined by patch clamp techniques. 5-HT produced a variety of responses such as outward (19/73 patches/neurons), slow inward (15/73 patches/neurons), fast inward (8/73 patches/neurons), and mixed currents (initially fast inward deflection followed by an outward response: 2/73 patches/neurons), with a latency of 12 sec, 15 sec, 0 sec, and 0 sec respectively, at a holding potential of −60 mV in whole-cell patches. The fast inward currents were again evoked by a selective 5-HT3 receptor agonist, 1-(m-chlorophenyl)-biguanide hydrochloride (CPBG). In the cell-attached patch clamp configuration, 5-HT inside the patch pipette elicited single channel currents with slope conductances of 42 pS and 132 pS (4/42 patches/neurons). CPBG inside the patch pipette evoked inward single channel currents with a lower slope conductance of 41 pS (3/23 patches/neurons). In contrast, application of 5-HT or a 5-HT₂ receptor agonist, α-methyl-5-hydroxytryptamine-maleate, outside the patch pipette induced outward single channel currents with a major slope conductance of 140 pS (8/30 patches/neurons) or 135 pS (6/20 patches/neurons), respectively. These results indicate that the outward and fast inward currents may be mediated respectively by the 5-HT₂ receptor, which is coupled to a G-protein, and by the 5-HT₃ receptor, which contains the non-selective cation channel, and that the mixed type may be caused by both the 5-HT₂ and 5-HT₃ receptors. Received 27 September 1996; received after revision 4 November 1996; accepted 7 November 1996     

表皮生长因子对猕猴胚胎角膜上皮组织增殖效应的研究

离体培养试验表明，小鼠颌下腺表此生长因子对离体培养猕猴胚胎眼角膜上皮组织具有显著促进细胞增殖和分化的效应。培养４ｄ的实验组角膜上皮的厚度，上皮细胞增殖层烽以及上皮组织中基底层细胞核与表层细胞核两者的比率均较正常猴胚角膜增长３倍。与此同时培养４ｄ的实验组角膜上皮厚度和上皮细胞的层数，都达到成年猴正常角膜上皮的结构水平。     

葡萄离体培养中胚状体发生的研究Ⅰ.胚状体发生的组织细胞学观察

以葡萄（ＶｉｔｉｓｖｉｎｉｆｅｒａＬ．）的花药和花丝为实验材料，观察了葡萄离体培养中胚状体的发生发育过程．结果表明：（１）葡萄的花药和花丝经诱导都可形成胚性和非胚性两类不同的愈伤组织，与外植体来源无关，胚状体经胚性愈伤组织产生．（２）胚状体多起源于胚性愈伤组织表层或表层以下的单个细胞，这些细胞核大，细胞质浓，染色深，在表层者易于脱落而处于单个离散状态，它们的第一次分裂有均等分裂，也有不等分裂，经２细胞、３细胞、多细胞原胚等阶段发育为成熟的胚状体．（３）葡萄胚状体具有与双子叶植物合子胚相似的发育过程     

发根农杆菌在植物细胞壁上受体位点的研究

刚分离的烟草和元麦叶肉原生的南体及用植物细胞壁再生抑制剂处理的上述原质体分别与发根农杆菌共培养，未发现农杆菌的附着；随着原生质体壁再生时间的延长，农杆菌的附着率逐渐的增加；用植物细胞主要组分的水解酶和ＴｒｉｔｏｎＸ－１００分别处理３日龄烟草叶肉原生质体后，进行随着菌数的放射性分析，结果表明，细菌对经过胰蛋白酶和ＴｒｉｔｏｎＸ－１００处理的细胞的附着率显著下降，ＴｒｉｔｏｎＸ－１００提取液中含有糖蛋     

5—HT1,5—HT2,5—HT3受体激动剂对离体蟾蜍心脏活动的影响

在离体蟾蜍心脏灌流标本中加入２．５，５．０，１０μｇ／２０μｌ三种不同剂量的（５－ＨＴ）后，可引起心输出量减少，心肌收缩力减弱，心率下降，并呈一定的量效关系。５－ＨＴ１受体激动剂ｐｉｐｅｒａｚｉｎｅ２．５，５．０，１０ｇ／２０μｌ时，对心率无明显影响，但可使心输出量增加，心肌收缩力加强，亦呈量效关系。     

Distribution of growth hormone-like immunoreactive cells and somatostatin receptors in the nervous system and Hatschek's pit of amphioxus, Branchiostoma belcheri

Using immunohistochemical method and double staining technique, the localization of growth hormone (GH) and somatostatin receptors in the nervous system and Hatschek's pit of amphioxus has been investigated. The results showed that the growth hormone-like nerve cells and endocrine cells as well as three subtypes of somatostatin receptors exist in the nervous system and Hatschek's pit, and GH-like nerve cells and endocrine cells co-exist with three subtypes of somatostatin receptors in the brain vesicle and Hatschek's pit. It is suggested that a primitive control system of inhibitory growth hormone secretion in Hatschek's pit could have been developed in amphioxus, as in vertebrates. The present study provides new evidence for the endocrinology and the evolution of Hatschek's pit.     

DRD3基因多态性与精神分裂症的相关性研究

目的 :研究多巴胺D3受体 (DRD3)基因的多态性与精神分裂症的关系。方法 :应用PCR -RFLP技术 ,在90名无亲缘关系的正常汉族人和80名精神分裂症患者中对DRD3基因第一外显子内Ser9Gly多态性进行分析。结果 :正常汉族人群中 ,DRD3等位基因1(Ser)和2(Gly)的频率分别为0.71和0.29。在正常对照组和精神分裂症组之间 ,等位基因频率 (X2=0.02,υ=1,P>0.05)和各种基因型 (P值均大于0.05)分布无显著性差异。结论 :DRD3基因的Ser9Gly多态性与中国汉族人群精神分裂症不相关。