金属硫蛋白对D-半乳糖致衰老大鼠学习记忆的影响

目的 观察不同剂量金属硫蛋白(MT)对D-半乳糖致衰老大鼠模型的学习记忆的改善作用.方法 Sprague-Dawley大鼠随机分为假手术组、模型组、MT剂量组(低0.46、中1.4和高4.2 mg/kg),每组10只.采用跳台法和Morris水迷宫实验检测大鼠的学习记忆功能,HE染色观察大鼠海马神经元形态变化,生化酶学法检测AChE、MAO-B、ChAT活性,黄嘌呤氧化酶法测定SOD,TBA法测定MDA.结果 D-半乳糖致衰老大鼠学习记忆能力明显下降,海马神经元核固缩;海马AChE、MAO-B活性明显增加(P＜0.01),ChAT活性明显降低(P＜0.01),给予外源性MT能以剂量依赖性的方式改善D-半乳糖致衰老大鼠学习记忆能力的损害、海马神经元损伤,并能明显阻遏D-半乳糖致衰老大鼠的海马AChE与MAO-B活性增加(低剂量组P＜0.05,中、高剂组P＜0.01),以及ChAT活性的降低(低剂量组P＜0.05,中、高剂量组P＜0.01).结论 MT能够改善D-半乳糖致衰老大鼠学习记忆功能,延缓脑组织的衰老.     

血管性认知功能障碍大鼠胆碱酯酶及胆碱乙酰化酶的表达

目的观察乙酰胆碱酯酶(AChE)和胆碱乙酰化酶(ChAT)在血管性认知障碍(VCI)大鼠脑内表达的变化。方法采用四血管法复制大鼠轻度认知功能障碍模型,并使用Morris水迷宫检测假手术组和造模2 w,1个月,3个月模型鼠的学习和记忆功能,对假手术组和造模2 w,1个月,3个月模型鼠脑内神经元的变化用苏木素-伊红(HE)染色和尼氏染色进行鉴定,然后用酶标仪测定大鼠血浆和海马AChE、ChAT酶活性,Western印迹检测大鼠大脑皮层AChE及ChAT蛋白的表达变化,免疫组织化学检测大鼠大脑皮层不同的区域AChE及ChAT的表达变化。结果在造模2 w模型鼠中未出现明显学习记忆障碍,1个月后出现记忆障碍和学习障碍,模型建立后1～3个月痴呆状况仍然持续并有下降趋势,且出现相应的神经细胞损伤及尼氏小体的丢失。与假手术组比较,模型组血浆中AChE酶活性下降,ChAT则相反。模型组脑内AChE蛋白表达增加,ChAT蛋白的表达减少;通过免疫组化结果显示,随着造模时间的延长,AChE的表达逐渐增加,ChAT则呈现逐渐减少趋势。结论持续的脑缺血、缺氧即可导致大鼠海马及血AChE表达升高,ChAT表达下降,且随着缺血时间的延长,这些改变更为明显,据此可初步认为胆碱能神经系统的改变与VCI发生发展密切相关。     

慢性脑低灌注大鼠海马组织中IDO的变化

目的观察慢性脑低灌注大鼠海马组织中干扰素(IFN-γ)、吲哚胺2,3-双加氧酶(IDO)的表达,探讨IDO在慢性脑低灌注导致认知功能损害中的作用。方法用双侧颈总动脉永久性结扎(2VO)制作慢性脑低灌注大鼠模型,Morris水迷宫检测2VO大鼠空间学习与记忆能力变化,免疫组化检测大鼠海马CA1区IFN-γ的表达,ELISA法检测IDO的表达。结果慢性脑低灌注大鼠的空间记忆能力较假手术组显著下降,海马IFN-γ、IDO表达较假手术组增加(P<0.05)。结论 IFN-γ刺激IDO合成增加,可能参与了慢性脑低灌注导致的认知功能损害。     

灵芝孢子粉对戊四氮慢性点燃大鼠学习记忆及胆碱乙酰转移酶、乙酰胆碱酯酶活性的影响

目的观察灵芝孢子粉对戊四氮点燃大鼠学习记忆及海马胆碱乙酰转移酶(ChAT)和乙酰胆碱酯酶(AChE)活性的影响,进一步探讨癫痫的发病机制及灵芝孢子粉对神经细胞保护的作用机制。方法将60只成年SD大鼠随机分为空白对照组、癫痫模型组、灵芝孢子粉用药高、中、低剂量组共5组。癫痫模型组和灵芝孢子粉用药各组大鼠腹腔注射阈下剂量的PTA35 mg.kg-1.d-1,直至达到点燃标准。点燃后,用药组以灵芝孢子粉灌胃。采用Morris水迷宫测试大鼠空间记忆能力,制备海马10%组织匀浆,化学比色法检测其ChAT、AChE的活性。结果水迷宫逃避潜伏期,模型组明显高于用药高剂量组和对照组(均P<0.01);跨过原平台次数,模型组明显少于用药高剂量组(P<0.05)和对照组(P<0.01);与模型组相比,用药中、高剂量组呈剂量依赖性显著抑制海马AChE的活性、增强ChAT的活性(均为P<0.05)。结论灵芝孢子粉可通过抑制功能脑区AChE活性、增加ChAT的活性,以增强中枢胆碱能神经系统的功能,改善癫痫大鼠认知能力,从而对脑组织起保护作用。     

丹黄通络胶囊对老年痴呆大鼠学习记忆能力及脑内胆碱能系统的影响

目的 观察丹黄通络胶囊对阿尔茨海默病(AD)模型大鼠学习记忆能力及脑内胆碱能系统的影响.方法 采用β淀粉样蛋白(Aβ25-35)侧脑室注射制备AD大鼠模型,用Morris水迷宫实验检测大鼠空间学习记忆能力,采用比色法测定大鼠脑组织中胆碱乙酰转移酶(ChAT)和乙酰胆碱酯酶( AchE)的活性,并应用免疫组化法检测海马神经元M1受体的表达.结果 丹黄通络胶囊组大鼠经治疗后,Morris水迷宫实验成绩明显优干模型组(P＜0.05);目脑组织中AchE活力明显降低,ChAT活力明显增强,海马神经元细胞膜上M1受体的平均灰度也明显降低,与模型组相比差异异具有统计学意义(P＜0.01),且呈现一定剂量依赖性.结论 丹黄通络胶囊对AD模型大鼠的学习记忆能力减退具有一定改善作用,其作用机制可能与保护中枢胆碱能系统有关.     

菖蒲四逆散干预AD模型大鼠Aβ代谢的级联靶效

目的 研究菖蒲四逆散对阿尔茨海默病(AD)模型大鼠学习记忆、海马 β 淀粉样蛋白前体(APP)、β-淀粉样蛋白(Aβ)1~42及血清超氧化物歧化酶(SOD)、丙二醛(MDA)、乙酰胆碱(Ach)、胆碱乙酰转移酶(ChAT)、乙酰胆碱酯酶(AChE)的影响,探讨菖蒲四逆散对AD模型大鼠Aβ代谢的干预及其与学习记忆能力、自由基氧化、神经递质改变的关联机制.方法 经水迷宫筛选合格的70只SPF级Wistar大鼠,随机选取10只为假手术组,其余大鼠脑立体定位注射Aβ25~35复制AD大鼠模型,以水迷宫学习记忆能力筛选造模成功的50只大鼠随机分为模型组、菖蒲四逆散低、中、高剂量组、阳性药组各10只.模型组与假手术组大鼠灌胃生理盐水2 ml/(100 g·d),菖蒲四逆散低、中、高剂量组及阳性药组大鼠分别灌胃对应药液2 ml/(100 g·d),连续28 d.给药25~28 d以Morris水迷宫测试各组大鼠学习记忆能力,然后取材检测海马APP、Aβ1~42及血清SOD、MDA、Ach、ChAT、AChE.结果 定位航行试验显示,与假手术组比较,模型组大鼠逃避潜伏期明显延长,在目标象限滞留时间较短;空间探索试验显示,首次到达原逃生平台位置的潜伏时间较长,穿越原平台位置及在目标象限滞留的时间明显较短,海马APP、Aβ1~42含量明显增高,血清SOD活性、ChAT活性、Ach水平明显降低,MDA水平、AchE活性明显增强(P<0.05,P<0.01).干预治疗后,与模型组比较,各给药组大鼠定位航行试验中逃避潜伏期均明显缩短,在目标象限滞留时间明显延长;空间探索试验中首次到达原平台位置潜伏期明显缩短,穿越原平台次数明显增多,海马APP、Aβ1~42明显降低血清SOD活性、ChAT活性、Ach水平明显提升,MDA水平、AchE活性明显降低(P<0.05,P<0.01).结论 菖蒲四逆散能有效改善AD模型大鼠学习记忆能力,其可能与通过干预AD模型大鼠海马Aβ代谢进而改善胆碱能神经递质、提升抗自由基氧化能力有关.     

复方田七益智颗粒对老年痴呆模型大鼠学习记忆及海马AChE活性的影响

目的 研究复方田七益智颗粒(CTG)对痴呆大鼠学习记忆及海马乙酰胆碱酯酶( AChE)活性的影响.方法 采用经典的大鼠Morris水迷宫实验,观察CTG对Aβ25～35致痴呆大鼠学习记忆障碍的改善作用,并测定CTG对痴呆大鼠海马AChE活性的影响.结果 在大鼠水迷宫实验中观察到CTG高剂量组(14g·kg-1·d-1)、中剂量组(7g· kg-1·d-1)、低剂量组(3.5 g·kg-1·d-1)大鼠逃避潜伏期、成功找到平台次数与模型组比较差异有统计学意义(P＜0.05或P＜0.01);测定大鼠海马AChE活性实验中观察到CTG高、中、低剂量组大鼠海马AChE活性与假手术组比较差异有统计学意义(P＜0.01).结论 CTG对Aβ25-35致痴呆大鼠学习记忆障碍具有明显的改善作用,且CTG可降低痴呆大鼠海马AChE活性,这可能是其改善学习记忆的药理机制之一.     

丹黄通络胶囊对自然衰老大鼠学习记忆能力的影响

目的探讨丹黄通络胶囊对自然衰老大鼠学习和记忆能力的影响。方法采用Morris水迷宫实验检测自然衰老大鼠空间学习和记忆能力,用比色法测定大鼠脑组织中胆碱乙酰转移酶(ChAT)和乙酰胆碱酯酶(AchE)的活性,并应用免疫组化法检测大鼠大脑皮质和海马神经元中Aβ1⁴0的表达。结果丹黄通络胶囊能明显改善自然衰老大鼠的学习和记忆能力;且显著降低AchE活力,升高ChAT活力;减少Aβ140的表达。结果丹黄通络胶囊能明显改善自然衰老大鼠的学习和记忆能力;且显著降低AchE活力,升高ChAT活力;减少Aβ1⁴0在海马和大脑皮质的表达。结论丹黄通络胶囊对自然衰老大鼠的学习记忆功能减退具有改善作用,其作用机制与恢复中枢胆碱能神经系统功能以及降低Aβ沉积有关。     

血管紧张素Ⅳ对糖尿病大鼠胆碱乙酰转移酶表达及认知功能的影响

目的 观察血管紧张素Ⅳ(AngⅣ)对糖尿病大鼠海马胆碱乙酰转移酶(ChAT)表达及认知功能的影响.方法 38只SD大鼠随机分为正常对照组、糖尿病组和糖尿病+AngⅣ组,建立STZ糖尿病大鼠模型, Morris水迷宫测试大鼠学习和记忆能力,免疫组化观察大鼠海马ChAT的表达,RT-PCR检测ChAT mRNA水平的表达.结果 糖尿病+ AngⅣ组海马chAT及其mRNA表达与糖尿病组相比明显增高(P<0.05),糖尿病+ AngⅣ组大鼠学习和记忆成绩也明显优于糖尿病组(P<0.05).结论 AngⅣ对糖尿病大鼠认知功能有改善作用,其机制可能与ChAT表达增加有关.     

地黄益智方对Aβ1～40所致老年性痴呆模型大鼠学习记忆能力的影响

目的观察地黄益智方对Aβ1～40所致老年性痴呆模型大鼠学习记忆能力的影响。方法 120只SD雄性大鼠随机分为正常组,模型组,地黄益智方小、中、大剂量组,采用大鼠双侧海马CA1区注射Aβ1～40复制老年性痴呆模型,造模24 h后开始给药,连续4 w。分别在给药1、3 w后用Morris水迷宫法连续5 d进行定位航行实验,第6天进行空间探索实验,检测各组大鼠学习记忆能力;2、4 w用生化法检测各组大鼠大脑皮层ChAT、AChE的活性变化。结果模型组大鼠明显存在学习记忆功能障碍,其中1 w后第2、4、5、6天与空白组相比有差异(P=0.016、0.000、0.003、0.001),3 w后第1、4、5、6天与空白组相比有差异(P=0.023、0.006、0.005、0.007),地黄益智方各剂量组行为障碍明显轻于模型组。模型组ChAT活性明显降低,2、4 w时与空白组相比有差异(P=0.011、0.024);模型组AChE活性明显增高,2、4 w时与空白组相比有差异(P=0.003、0.010);地黄益智方各剂量组乙酰胆碱转移酶(ChAT)、乙酰胆碱酯酶(AChE)活性改变明显轻于模型组。结论地黄益智方能改善Aβ1～40所致老年性痴呆模型大鼠学习记忆能力,可能与其调节中枢神经递质ChAT、AChE活性有关。     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the M_r range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [¹²⁵I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (K_a of 4.7 ± 0.2 × 10⁹ M^-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of M_r 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.     

Microbiology of human immunodeficiency virus anorectal disease

PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.