Changes of mu and kappa opioid receptors in cathartic colon of rat

Objective: To observe the changes of mu and kappa opioid receptors in the cathartic colon of rat, and to clarify that whether opioid receptors accounts for the occurrence of slow transit constipation (STC). Methods: The cathartic colon model of rat was made by feeding with laxatives. The activity of mu and kappa opioid receptors in the cathartic colon of rat was measured by radio-ligand binding assay. Results: Compared with the control group, the maximal binding capacity (Bmax) and affinity(Kd) of mu opioid receptor in cathartic colon group were significantly increased (207.00±22.90 fmol/mg·p vs 82.00±14.23 fmol/mg·p, P < 0.01;3.30±0.45 mmol/L vs 2.40±0.57 mmol/L,P < 0.05). The maximal binding capacity of kappa opioid receptor also showed a great increase (957.00±102.41 fmol/mg·p vs 459.00±52.41 fmol/mg·p, P<0.01), but no significant difference of affinity was found between the two groups. Conclusion: The mu and kappa opioid receptors may be involved in the functional disorders of cathartic colon.

Effects of Peripherally Acting Opioid Ligands on Central Opioid Receptors and <i>β</i>-Endorphin Release in Stressed Rats

Using the radioreceptor binding assay, μ-opioid receptor (MOR) affinity in the midbrain of stressed rats was higher than in naive controls. MOR density in the rat frontal cortex was reduced after stress. Intragastric administration of the MOR antagonist naloxone methiodide was followed by an increase in the number of MORs in the frontal cortex. However, the MOR agonist loperamide significantly decreased the density of MORs in the frontal cortex and midbrain of naive animals. Loperamide and naloxone methiodide were shown to prevent an increase in MOR affinity and a decrease in MOR density in the midbrain of rats after restraint stress. The restraint stress was accompanied by an increase in the release of β-endorphin (BE) in the ventral tegmental area (VTA) of control rats. After administration, loperamide slightly decreased the release of BE, naloxone methiodide significantly increased the release of BE in the cingulate cortex (CC) of untreated animals, while drugs had no effect on the release of BE in the VTA. The drugs significantly increased the extracellular level of BE in the CC of stressed animals. Loperamide abolished the increase in the stress-induced release of BE in the VTA. By contrast, naloxone methiodide significantly increased the release of BE in the VTA of stressed rats. Our data indicated that activation of peripheral MORs induces depression of the central part of the μ-opioid system, but suppression of peripheral MOR activity induces activation of the central μ-opioid system, the interaction of which can be modulated by stress.

MODULATION OF A δ-AND C-FIBER EVOKED RESPONSES OF NOCICEPTIVE NEURONS IN THE SUPERFICIAL AND THE DEEPER DORSAL HORN OF THE MEDULLA:ROLE OF OPIOID RECEPTORS(μ, δ_1, δ_2)

The present study was designed to investigate the effects of intravenously administered agonists and antagonists at μ(DAMGO, naloxone,)δ1 (DPDPE,BNTX)andδ2(DELT, NTB)opioid receptors on the Aδ-and C-fiber evoked responses of nociceptive neurons in the superficial and the deeper dorsal horn of the rat medulla.Extracellular single unit recording were made from 70 nociceptive neurons(28 NS,42 WDR) in the superficial dorsal horn and 37 nociceptive neurons(4 NS,33 WDR)in the deeper dorsal horn.All these neurons had an ipsilateral orofacial mechanoreceptive field and majority of these neurons had no spontaneous activity. The latencies for the C fiber evoked responses ranged from 34～105 msec whereas for Aδfiber-evoked responses it ranged from 3～22msec. A clear separation was observed between early and late responses of evoked by Cand Aδ-fiber.Application of DPDPE,DELT and DAMGO produced inhibitory effects on the Aδ-and C-fiber evoked responses of nociceptive neurons in the superficial and thedeeper dorsal horn.By comparison,the inhibition was more pronounced on the C-fiber evoked response than on the Aδ-fiber evoked response,and DAMGO produced a stronger inhibitory action than both DELT and DPDPE. Additionally,DPDPE produced facilitation, or inhibition followed by facilitation on the Aδ-and C-response and the effect had longer latency and longer time course.DPDPE also induced completely oppsite effects on the Aδ-and C-fiber evoked responses.Although the facilitation was observed,the effect was not dose-dependent. Application of BNTX (0.4～1mg/kg),a δ1 receptor antagonist,produced antagonism of DPDPE in 88%(7/8) neurons. Application of the doses (0.7～1mg/kg) of BTB,δ2-receptor antagonist,resulted in antagonism of both DELT and DPDPE. The inhibition of DELT on Aδ-response was antagonized by doses (0.3～1mg/kg)of NTB in 100% (14/14)neurons while the antagonism on C-response was in 79%(11/14) neurons.The effect produced by DPDPE was antagonized by the doses (0.7～1mg/kg) of NTB in 100%(4/4) neurons. However,a smaller dose of NTB(0.3mg/kg)which and antagonize the effect of DELT,did not antagonize the effect of DPEPE in 100%(4/4) neurons. The inhibitory action of DAMGO on Aδ-and C-fiber evoked responses was completely antagonized by naloxone(0. 2mg/kg) in 100% (6/6) neurons. These results suggest that:①μ-and δ-opioid receptors play an important role in modulating Aδ-and Cfiber evoked responses of nociceptive neurons in the superficial and the deeper dorsal horn of the rat medulla; ② The inhibitory action produced by DPDPE, DELT and DAMGO was more pronounced on the C-fiber evoked excitation and indicates that the agonists produce more predominant inhibition on the responses of dorsal horn neurons to noxious stimuli; ③ activation of either δ1-orδ2-opioid receptors produces inhibitory actions on Aδ- and C-response of nociceptive neurons in the superficial and the deeper dorsal horn of the medullal;DPDPE and DELT act at different δ-opioid receptor subtypes in the rat rnedulla; ⑤i.v.-administered NTB can distinguish δ-opioid receptor subtypes in a limited dose range.When administered i. v., 0. 3mg/kg of NTB is selective for δ2-opioid receptor.

YFa and analogs:Investigation of opioid receptors in smooth muscle contraction

AIM:To study the pharmacological profile and inhibition of smooth muscle contraction by YFa and its analogs in conjunction with their receptor selectivity. METHODS:The effects of YFa and its analogs (D-Ala2) YFa, Y (D-Ala2) GFMKKKFMRF amide and Des-Phe-YGGFMKKKFMR amide in guinea pig ileum (GPI) and mouse vas deferens (MVD) motility were studied using an isolated tissue organ bath system, and morphine and DynA (1-13) served as controls. Acetylcholine was used for muscle stimulation. The observations were validated by specific antagonist pretreatment experiments using naloxonazine, naltrindole and norbinaltor-phimine norBNI. RESULTS:YFa did not demonstrate significant inhibition of GPI muscle contraction as compared with mor-phine (15% vs 62%, P = 0.0002), but moderate inhibition of MVD muscle contraction, indicating the role of κ opioid receptors in the contraction. A moderate inhibition of GPI muscles by (Des-Phe) YFa revealed the role of anti-opiate receptors in the smooth muscle contraction. (D-Ala-2) YFa showed significant inhibition of smooth muscle contraction, indicating the involvement of mainly δ receptors in MVD contraction. These results were supported by specific antagonist pretreatment assays. CONCLUSION:YFa revealed its side-effect-free analgesic properties with regard to arrest of gastroin-testinal transit. The study provides evidences for the involvement of κ and anti-opioid receptors in smooth muscle contraction.

Binding properties of C-truncated delta opioid receptors

目的：研究δ阿片受体Ｃ末端在受体结合配体的亲和力及选择性中的作用．方法：在中国苍鼠卵巢细胞（ＣＨＯ细胞）中分别稳定表达Ｃ末端截短３１个氨基酸残基及野生型δ阿片受体，用受体结合分析法研究表达产物与配体的结合特征．结果：表达得到典型突变受体克隆ＣＨＯＴ及野生型受体克隆ＣＨＯＷ．ＣＨＯＴ结合［３Ｈ］ｄｉｐｒｅｎｏｒｐｈｉｎｅ（Ｄｉｐ）及［３Ｈ］［ＤＡｌａ２，ＤＬｅｕ５］ｅｎｋｅｐｈａｌｉｎ（ＤＡＤＬＥ）的Ｋｄ值与ＣＨＯＷ一致，δ选择性激动剂对二者与［３Ｈ］Ｄｉｐ的结合均有很强的抑制作用，且Ｋｉ相似；而μ及κ选择性激动剂则对二者均无抑制作用．结论：δ阿片受体的Ｃ末端与受体结合配体的亲和力及选择性无关．

Expression of mu-opioid receptors in human chronic inflamed knee joint synovium tissue

Objective: To examine the changes of mu-opioid receptors (MORs) expression in human chronic inflamed knee joint synovium tissue. Methods:Knee joint synovium tissues were taken from 21 patients with chronic arthritis (inflamed group) and 6 fresh bodies with normal knee joints (control group). And the expression of MORs was detected by using immunohistochemistry. flow cytometry(FCM) and reverse-transcription polymerase chain reaction (RT-PCR). Results: The expression of MORs in the inflamed group was significantly higher than that in the normal group by using the 3 techniques(P<0. 05). Conclusion: Chronic inflammation enhances the up-regulation of MORs in human knee joint synovium tissue.

Low-dose morphine elicits ventilatory excitant and depressant responses in conscious rats: Role of peripheral <i>µ</i>-opioid receptors

The systemic administration of morphine affects ventilation via a mixture of central and peripheral actions. The aims of this study were to characterize the ventilatory responses elicited by a low dose of morphine in conscious rats;to determine whether tolerance develops to these responses;and to determine the potential roles of peripheral μ-opioid receptors (μ-ORs) in these responses. Ventilatory parameters were monitored via unrestrained whole-body plethysmography. Conscious male Sprague-Dawley rats received an intravenous injection of vehicle or the peripherally-restricted μ-OR antagonist, naloxone methiodide (NLXmi), and then three successive injections of morphine (1 mg/kg) given 30 min apart. The first injection of morphine in vehicle-treated rats elicited an array of ventilatory excitant (i.e., increases in frequency of breathing, minute volume, respiratory drive, peak inspiratory and expiratory flows, accompanied by decreases in inspiratory time and end inspiratory pause) and inhibitory (i.e., a decrease in tidal volume and an increase in expiratory time) responses. Subsequent injections of morphine elicited progressively and substantially smaller responses. The pattern of ventilatory responses elicited by the first injection of morphine was substantially affected by pretreatment with NLXmi whereas NLXmi minimally affected the development of tolerance to these responses. Low-dose morphine elicits an array of ventilatory excitant and depressant effects in conscious rats that are subject to the development of tolerance. Many of these initial actions of morphine appear to involve activation of peripheral μ-ORs whereas the development of tolerance to these responses does not.

Dopamine D₁- and D₂-Receptors in Immunostimulation under Activation of Mu-Opioid Receptors in Mice with Different Psychoemotional States

The purpose of the present study was to analyze the effect of activation of mu-opioid receptors (mu-OR) on the immune response under blockade of postsynaptic D1-and D2-receptors in mice of the C57BL/6J strain displaying either aggressive or depressive-like behaviors in the social conflict model. It is shown that activation of activation of mu-OR with a highly selective agonist DAGO (100 μg/kg) increased significantly IgM-immune response not only in C57BL/6J mice with an unchanged psychoemotional state but also in mice displaying aggressive or depressive-like behaviors in the social stress model (10 days of agonistic confrontations). Selective blockade of DA receptors of the D1-type with SCH-23390 (1.0 mg/kg with DAGO administration) caused a more pronounced elevation of IgM-immune response than DAGO alone while DAGO effect was completely blocked by prior administration of D2-receptor antagonist haloperidol (1.0 mg/kg). At the same time, both SCH-23390 and haloperidol prevented the immune response increase induced by DAGO injection in mice engaged in aggressive or depressive-like behaviors. Thus, in animals not subjected to social stress DAGO-induced immunostimulation is provided only by D2-receptors, whereas in animals with altered psychoemotional state mu-opioid immunostimulation is mediated by both types of DA receptors—D1 and D2. These data provide evidence for different impacts of the main subtypes of DA receptors in the mediation of immunomodulating effects of mu-opioid system under normal and stressful conditions.

Role of opioid receptor heterodimerization in pain modulation and tolerance development

Protein to protein interactions leading to homo/heteromerization of receptor is well documented in literature. These interactions leading to dimeric/oligomers formation of receptors are known to modulate their function, particularly in case of G-protein coupled receptors. The opioid receptor heteromers having changed pharmacological properties than the constituent protomers provides preferences for novel drug targets that could lead to potential analgesicactivity devoid of tolerance and physical dependence. Heterodimerization of opioid receptors appears to generate novel binding properties with improved specificity and lack of side effects. Further the molecules which can interact simultaneously to both the protomers of the heteromer, or to both the binding sites(orthosteric and allosteric) of a receptor protein could be potential therapeutic molecules. This review highlights the recent advancements in exploring the plausible role of heteromerization of opioid receptors in induction of tolerance free antinociception.

Determination of structure-activity relationships between fentanyl analogs and human μ-opioid receptors based on active binding site models

Fentanyl is a potent and widely used clinical narcotic analgesic, as well as a highly selective IJ-opioid agonist. The present study established a homologous model of the human μ-opioid receptor; an intercomparison of three types of μ-opioid receptor protein sequence homologous rates was made. The secondary receptor structure was predicted, the model reliability was assessed and verified using the Ramachandran plot and ProTab analysis. The predictive ability of the CoMFA model was further validated using an external test set. Using the Surflex-Dock program, a series of fentanyl analog molecules were docked to the receptor, the calculation results from Biopolymer/SitelD showed that the receptor had a deep binding area situated in the extracellular side of the transmembrane domains （TM） among TM3, TM5, TM6, and TMT. Results suggested that there might be 5 active areas in the receptor. The important residues were Asp147, Tyr148, and Tyr149 in TM3, Trp293, and His297 in TM6, and Trp318, His319, Ile322, and Tyr326 in TM7, which were located at the 5 active areas. The best fentanyl docking orientation position was the piperidine ring, which was nearly perpendicular to the membrane surface in the 7 TM domains. Molecular dynamic simulations were applied to evaluate potential relationships between ligand conformation and fentanyl substitution.

Delta阿片受体参与低氧预处理减轻心肺复苏脑损伤的研究

目的研究delta阿片受体(DOR)是否参与了低氧预处理(HPC)对心肺复苏大鼠脑损伤的保护作用。方法 90只大鼠接受为期7d的HPC后,建立大鼠窒息性心肺复苏脑损伤模型,随机均分为五组:心跳停止(CA)组(A组)、HPC+CA组(B组)、Naltrindole(NTI,DOR特异性拮抗药)+CA组(C组)、HPC+人工脑脊液(ACSF)+CA组(D组)及HPC+NTI+CA组(E组)。A组仅建立心肺复苏模型;C组大鼠在窒息前30min经侧脑室注入含50nmolNTI的ACSF10μl;B、D、E组均接受连续7d的HPC,HPC结束后24h,B组大鼠接受气管插管、8min窒息以及心肺复苏;而D组和E组大鼠则在窒息前30min分别经侧脑室注入含0或50nmolNTI的ACSF10μl。观察复苏成功率并对存活大鼠的神经功能缺损进行评分,观察复苏后海马CA1区神经元损伤及凋亡情况。结果 HPC改善心肺复苏脑损伤后的神经功能缺损,抑制早期海马神经元的凋亡,增加海马CA1区存活神经元的数量,而DOR拮抗药Naltrindole明显消除了HPC的神经保护作用。结论在HPC减轻心肺复苏大鼠脑损伤的过程中,DOR发挥着重要作用。

Delta阿片受体、β-arrestin1、Bcl-2在溃疡性结肠炎大鼠脾脏组织中的表达及乌梅丸的干预作用

目的:观察溃疡性结肠炎(ulcerative colitis,UC)大鼠脾脏组织Delta阿片受体、β-arrestin1、Bcl-2 mRNA和蛋白表达及乌梅丸的干预作用,旨在研究乌梅丸治疗结肠炎的机制.方法:56只SD大鼠随机分成空白对照组、结肠炎模型组、美沙拉嗪组、乌梅丸组(每组14只).除空白对照组外,其他3组均应用2,4,6-三硝基苯磺酸灌肠.模型建成2 d后,空白对照组和结肠炎模型组分别以蒸馏水3 mL/只灌胃,美莎拉嗪组用美莎拉嗪混悬液(浓度50 g/L)、乌梅丸组用乌梅丸液(浓度0.51 g/L)以3 mL/只灌胃,连续给药15 d后取脾脏组织,应用Realtime-PCR检测Delta阿片受体、β-arrestin1、Bcl-2 mRNA的表达,应用Western blot技术检测Delta阿片受体、β-arrestin1、Bcl-2蛋白的表达.结果:空白对照组Delta阿片受体、β-arrestin1及Bcl-2 mRNA的相对表达分别为1.11±0.10、1.05±0.06及1.06±0.04;蛋白的相对表达分别为0.48±0.08、0.62±0.07及0.76±0.10.结肠炎模型组Delta阿片受体、β-arrestin1及Bcl-2的mRNA的相对表达分别为2.50±0.25、3.27±0.41及2.48±0.43;蛋白的相对表达分别为1.04±0.17、1.50±0.15及1.26±0.20.美沙拉嗪组Delta阿片受体、β-arrestin1及Bcl-2 mRNA的相对表达分别为1.52±0.09、1.63±0.27及1.56±0.09;蛋白的相对表达分别为0.68±0.17、0.77±0.15及0.96±0.16.乌梅丸组Delta阿片受体、β-arrestin1及Bcl-2 mRNA的相对表达分别为1.54±0.13、1.54±0.14及1.57±0.15;蛋白的相对表达分别为0.68±0.14、0.74±0.19及0.93±0.11.与空白对照组相比,结肠炎模型组Delta阿片受体、β-arrestin1、Bcl-2 mRNA和蛋白表达显著升高(P<0.05);与结肠炎模型组相比,乌梅丸组、美沙拉嗪组Delta阿片受体、β-arrestin1、Bcl-2 mRNA和蛋白表达显著下降(P<0.05),且乌梅丸组和美沙拉嗪组Delta阿片受体、β-arrestin1、Bcl-2 mRNA和蛋白表达均无显著差异(P>0.05).结论:乌梅丸下调UC大鼠脾脏组织Delta阿片受体、β-arrestin1、Bcl-2 mRNA和蛋白表达发挥治疗结肠炎的作用.

Delta阿片受体激活通过调节JAK2/STAT3通路减轻肝硬化大鼠缺血再灌注损伤

目的研究Delta阿片受体激活对肝硬化大鼠肝脏缺血再灌注(ischemia reperfusion,IR)损伤的保护作用以及相关机制。方法选择雄性健康Sprague-Dawley大鼠,建立肝硬化模型。随后32只大鼠随机分为4组(n=8),分别为假手术组(SHAM组)、对照组(CON组)、Delta阿片受体激动剂预处理组(DADLE组)、Delta阿片受体拮抗剂组(NTD组)。再灌注6 h后,通过H&E染色评分,测血清丙氨酸氨基转移酶(alanine transaminase,ALT)和天冬氨酸氨基转移酶(aspartate transaminase,AST)水平。使用酶联免疫吸附试验检测血清肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)以及白介素-1β(interleukin-1β,IL-1β)的含量。采用荧光定量反转录-聚合酶链反应以及蛋白印迹法检测Janus激酶2(Janus kinase 2,JAK2)和信号转导及转录激活因子-3(signal transducer and activators of transcription 3,STAT3)的表达。结果与CON组相比,DADLE明显降低血清ALT[(138±33.369)U/L vs.(267±106.173)U/L,P <0.05]和AST[(210±102.666)U/L vs.(374±64.021)U/L,P <0.05]。DADLE组H&E染色评分明显低于CON组(4.83±1.169 vs.7.67±0.816,P <0.05)。与CON组相比,DADLE明显降低了TNF-α[(15.561±5.12)pg/mL vs.(32.289±9.23)pg/mL,P <0.05]和IL-1β的含量[(46.444±7.777)pg/mL vs.(68.841±9.225)pg/mL,P <0.05]。使用DADLE后,JAK2和STAT3的mRNA表达增高(P <0.05),磷酸化蛋白含量也明显升高。然而NTD组与CON组相比差异无统计学意义(P> 0.05)。结论 Delta阿片受体激活能减轻硬化肝脏IR损伤,其机制可能与调节JAK2/STAT3通路有关。

瑞芬太尼痛觉过敏大鼠Delta阿片受体mRNA的表达水平

目的：探讨切口痛-瑞芬太尼痛觉过敏大鼠背根神经节及海马Delta阿片受体mRNA表达水平的变化。方法：健康雄性SD大鼠32只，尾静脉置管后随机分为4组，瑞芬太尼组（R组）输注瑞芬太尼1μg·kg-1·min-1，切口痛组（I组）输注等体积生理盐水，甘氨酸组（G组）输注甘氨酸15μg·kg-1·min-1，对照组（C组）输注等体积生理盐水，最后一次痛阈测定后留取大鼠L4-L6背根神经节及海马标本，应用实时定量PCR方法测定Delta阿片受体mRNA的表达水平。结果：R组、I组、G组均发生痛觉过敏，且R组痛觉过敏的程度高于I组和G组；R组海马Delta阿片受体mRNA表达水平（4.359±1.031）显著高于C组、I组（2.373±1.014）和G组（2.411±0.326）（P＜0.05）；R组背根神经节Delta阿片受体mRNA表达水平（2.108±0.361）显著高于C组、I组（1.409±0.435）和G组（1.413±0.234）（P＜0.05）。结论：瑞芬太尼可在切口痛模型大鼠中引发痛觉过敏，其机制可能与背根神经节及海马Delta阿片受体mRNA表达上调有关。

Mu-、kappa-、delta-阿片受体在成年大鼠正常胃组织的免疫组织化学定位研究

目的观察mu-、kappa-、delta-阿片受体在成年大鼠正常胃组织中的分布与定位。方法选用成年雄性wistar大鼠胃组织切片进行免疫组织化学染色,用免疫组织化学技术对Mu-、kappa-、delta-阿片受体在大鼠胃组织的分布进行定位分析。结果mu-阿片受体免疫阳性物质主要分布于胃黏膜上皮及黏液层、胃主细胞、肌间神经丛等部位;kappa-、delta-阿片受体免疫阳性物质主要分布于胃主细胞、肌间神经丛等部位。结论mu-、kappa-、delta-阿片受体在胃主细胞膜和胞浆、肌间神经丛等部位均有分布,但仅mu-阿片受体还存在于胃黏膜上皮及黏液层,提示阿片受体参与了胃各种生物学功能及胃粘膜的损伤、修复与再生。

Delta阿片受体激活对体外培养大鼠软骨细胞凋亡的影响

目的：研究delta阿片受体激活对体外培养新生大鼠软骨细胞凋亡的影响并探讨其机制。方法：体外分离培养新生大鼠软骨细胞，用delta阿片受体进行干预，MTT法测定细胞活力；AnnexinV-FITC／PI双标记法测定细胞凋亡；免疫印迹分析caspase-3和细胞外信号调节激酶（ERK）蛋白表达水平。结果：delta阿片受体激动剂DADLE（1 μmol／L）可增强软骨细胞ERK蛋白的磷酸化，抑制软骨细胞凋亡，但这种现象可被delta阿片受体阻断剂Naltrindole（10μmol／L）所逆转，并且给予ERK特异性抑制剂U0126（10μmol／L）亦可逆转DADLE抑制细胞凋亡的作用。结论：Delta阿片受体激活可抑制大鼠软骨细胞凋亡，其机制可能与激活ERK途径相关。

Delta阿片受体激动剂DADLE在大鼠缺血性脑损伤中的作用

目的研究delta阿片受体激动剂DADLE([D-Ala2,D-Leu5]-enkephalin)在大鼠全脑缺血性脑损伤中的作用。方法 60只成年健康雄性Sprague-Dawley大鼠被随机分入6组,每组10只:假手术对照(Sham)组、人工脑脊液(ACSF)组、DADLE0.2mmol/L(DADLE0.2)组、DADLE2mmol/L(DADLE2)组、DADLE20mmol/L(DADLE20)组和DADLE2mmol/L+纳曲吲哚2mmol/L(联合用药)组。应用立体定位技术分别对各组大鼠的左侧侧脑室注射相应剂量的实验药物10μL。45min后对大鼠行全脑缺血10min,5d后进行运动功能和水迷宫检测,最后处死动物进行脑组织病理学检查。结果 ACSF组的运动功能评分显著低于其他5组(P值均<0.05);3个不同剂量DADLE组间差异均有统计学意义(P值均<0.05),DADLE20组最高,联合用药组显著低于DADLE2和DADLE20组(P值均<0.05)。术后7、8d,ACSF组的水迷宫检测潜伏期均显著长于同时间点的其他5组(P值均<0.05);3个不同剂量DADLE组间同时间点潜伏期的差异均有统计学意义(P值均<0.05),DADLE20组最短,联合用药组均显著长于同时间点的DADLE20组(P值均<0.05)。同时间点各组间及同组各时间点间游泳速度的差异均无统计学意义(P值均>0.05)。术后6、7、8d,ACSF组的目标象限游泳时间均显著短于同时间点的其他5组(P值均<0.05);3个不同剂量DADLE组同时间点目标象限游泳时间的差异均有统计学意义(P值均<0.05),DADLE20组最长,联合用药组均显著短于同时间点的DADLE20组(P值均<0.05)。ACSF组海马CA1区的存活神经元数目显著少于其他5组(P值均<0.05),DADLE剂量依赖性地增加海马CA1区的存活细胞数,3个不同剂量DADLE组同时间点的差异均有统计学意义(P值均<0.05),联合用药组显著少于DADLE2组(P<0.05)。结论 DADLE侧脑室注射具有明显减轻缺血性脑损伤的效应,其作用呈剂量依赖性,其机制主要是激活delta受体,同时亦可能有其他机制参与。

Impact of Oil and Gas Activities on Acidity of Rain and Surface Water of Niger Delta, Nigeria: An Environmental and Public Health Review

Acidic aerosols resulting from gas flaring and refinery operations in the Niger Delta are a serious environmental and public health concern. Several thousand tons of flue gas components (dust particles, SOx, CO and NOx) are released into the atmosphere by flaring billions of cubic meters of natural gas, refining and volatilizing the spilt oil. Heat wave is generated by flaring travels several meters away from flare points, destroying crops, farm lands, exotic species that are hunters delight while causing extinction of fragile soil flora and fuana. The occurrence of acid rain in the region implies that the natural receptors of the area are the final recipient of land and atmospheric pollutants. In effect, the water needs and public health of the populace are greatly impeded. Nitric and sulphuric acids are regarded as the sole contributors of nitrate and sulphate in precipitation influenced by combusted hydrocarbons: fine nitrate aerosols that dissolve in rain water are conversion products of NO2 that arise from flaring, power plants and motor vehicles. Scientific evidence has shown that rain water and surface water quality in the Niger Delta can accentuate the poor health burden, and may be perpetuated through generations unborn. Diagnostic health risk assessment has revealed that drinking nitrate contaminated water may be associated with spontaneous miscarriage, ectopic pregnancy, adult malignant lymphomas, soft tissues sarcomas, cancers and lesions with added health burden associated with heavy metals and other ions. All these pose public health emergency and may significantly entrench health risk for generations to come. Therefore, this manuscript is intended to close certain gaps that were not covered by toxicological information and available data on environmental and food contamination and human internal exposure: it will serve as a continuous reminder and a useful guide to public health policy makers, workers and community based physicians.

Delta-1对IL-6R^+髓系祖细胞分化的影响

目的探讨Notch配体Delta-1在髓系造血细胞分化过程中对膜结合和可溶性IL-6受体所介导信号的调节作用。方法分离正常脐血单核细胞,然后利用CD34免疫磁珠试剂盒和FACSVantage流式细胞仪从所获单核细胞中拣选CD34+CD38-细胞;将CD34+CD38-细胞利用SCF、Flt3L、TPO和IL-3(4GFs)培养7 d,用CD36免疫磁珠试剂盒分离掉培养细胞中的CD36+红系祖细胞,然后用FACSVantage流式细胞仪将细胞再次拣选出CD15-CD14-CD1a-IL-6R+表型的细胞,将这种表型的细胞用含有4GFs、4GFs+IL-6或4GFs+FP6培养基在有或无Delta-1存在的条件下进行培养11 d,并对CD15+粒细胞、CD14+单核细胞和CD14-CD1a+树突状细胞进行计数。结果发现所有CD15、CD14或CD1a阳性的细胞均表达IL-6R;IL-6和FP6可促进CD15+细胞的分化;Delta-1在无IL-6和FP6存在时对CD15+细胞的分化表现出轻度的抑制作用;在IL-6和FP6存在时对CD15+粒细胞的分化表现出明显的抑制作用;相反,IL-6和FP6抑制CD14-CD1a+细胞的分化,而Delta-1促进CD14-CD1a+细胞的分化。结论Delta-1可通过抑制mIL-6R-和sIL-6R所介导的IL-6生物学效应抑制IL-6R+髓系祖细胞分化为粒细胞和单核细胞,但促进其分化为树突状细胞。