Morphologic analysis of rat retinocollicular neuron terminals containing monoamine oxidase

The retino-collicular neuron terminals containing type A monoamine oxidase (MAO-A) in the stratum griseum superficiale of the rat superior colliculus were analyzed to provide a morphologic basis for the physiologic role of these neurons in the visual pathway. A computer-assisted, three-dimensional re-construction of the terminal complex associated with the MAO-A-positive terminals was performed. MAO-A-positive terminals originated in the retina and terminated in the stratum griseum superficiale. This was confirmed by tract tracing and enucleation experiments. The terminals were densely grouped in clusters of irregularly shaped swellings. Electron microscopy revealed that the MAO-A-positive terminals were located in a glomerulus-like structure. In this terminal complex, a significant proportion of the axonal profiles (42.96%) synapsed with the MAO-A-positive terminals. Most of the profiles (24.16%) resembled presynaptic dendrites, which represent intermediate elements between the retinal terminals and conventional dendrites. Unlike the glomerulus in the dorsal lateral geniculate body, the MAO-A-positive terminal swellings were not located in the central part of the terminal complex. The terminals had an irregular shape and were located in the complex. The terminal complex was partially ensheathed by glial processes. Furthermore, the membrane surfaces exhibiting synaptic specializations were very small compared with the total surface of the terminal swellings. The membrane length of the synaptic specialization was 5.38% of the total perimeter of the MAO-A-positive terminals.     

Characterization of mouse allergens

The major allergens present in mouse skin, serum, and urine have been identified. Skin extracts, serum, and urine were chromatographed, and the activities of the fractions were monitored by histamine release from the leukocytes of individuals sensitive to mice. Fractionation of skin extracts revealed two major allergens. The large allergen has a molecular weight of approximately 67,000 daltons and by biochemical and immunochemical criteria appears to be identical to mouse albumin. The smaller molecular weight allergen is approximately 17,000 daltons. The same two allergens are also found in mouse serum and mouse urine. Histamine release by leukocytes of individuals allergic to mice demonstrated that some individuals react predominantly to the large allergen, some to the small allergen, and one group of patients reacts to both allergens.     

低营养及低氧状态下NIH3T3细胞增殖及细胞周期的变化及对bFGF的影响

目的： 体外模拟慢性创面缺氧、低营养环境，观察成纤维细胞在该状态下增殖及细胞周期的变化及对外源性生长因子（bFGF）的反应,探讨低氧、低营养条件下成纤维细胞的病理生理变化。方法: 单纯缺氧环境采用厌氧培养箱，通入混合气，氧分压（PO₂）分为27 mmHg和44 mmHg 2个水平；低营养环境则控制培养液新生牛血清（NCS）浓度。用MTT法检测细胞活性以及其对外源性生长因子的反应，用流式细胞仪检测细胞周期。结果: PO₂ 44 mmHg时细胞增殖速度较同期对照组无明显差异；PO₂ 27 mmHg时，细胞增殖速度较同期对照组明显减慢（P<0.01），细胞被阻滞于G₀期，S期细胞比例明显减少，bFGF未显示促增殖作用。NCS浓度为0.5%的低营养状态下细胞增殖速度较同期对照组明显减慢（P<0.01），细胞被阻滞于G₀-G₁期（P<0.01）；bFGF能明显改善低营养状态下的增殖减慢（P<0.01），使G₂-M期细胞比例增加（P<0.05）。结论: 27 mmHg PO₂或NCS浓度为0.5%的低营养环境使细胞阻滞于G₀-G₁期，影响成纤维细胞增殖；bFGF可以改善低营养条件下细胞增殖减慢的状态，但对极度缺氧条件下的成纤维细胞增殖障碍无明显作用。     

Reserpine as an uncoupler of oxidative phosphorylation and the relevance to its psychoactive properties

Many drugs differing widely in chemical structure uncouple mitochondrial oxidative phosphorylation in vitro. This observation has led to the hypothesis that in vivo uncoupling is the basis of their pharmacological activity. Serpasil, a parenteral preparation of reserpine, recently has been shown to uncouple oxidative phosphorylation in vervet monkey kidney mitochondria. Although the drug exhibits some properties of a "classical" uncoupler, our studies show that it has a dual effect on energy conservation. Reserpine released respiratory control in rat liver mitochondria only when dissolved in organic solvents (as in Serpasil) or when deprotonated. Reserpine also released the oligomycin-induced respiratory control in beef heart submitochondrial particles, and inhibited energized uptake of Ca2- by rat liver mitochondria. Reserpine had a dual effect on mitochondrial ATPase: It (a) enhanced ATP hydrolysis by intact liver mitochondria, and (b) inhibited ATP hydrolysis by submitochondrial particles of beef heart. On a molar basis, reserpine was less effective than carbonyl cyanide 3-chlorophenylhydrazone in all bioenergetic reactions examined. Homogenates and mitochondria isolated from brain and liver of rats stuporous from intraperitoneally injections of Serpasil exhibited no detectable abnormalities in respiratory states and responded to known uncouplers in the expected manner. There was no evidence of in vivo uncoupling of oxidative phosphorylation as a basis of the pharmacological activity of reserpine, although interference with energy transfer may be involved in toxic manifestations of the drug. The results indicate the need for caution in interpreting the action of drugs formulated in complex pharmaceutical preparations and based solely on in vitro experiments.     

细菌脂多糖对NIH3T3细胞增生、胞内游离钙及cAMP浓度的影响

目的 :探讨细菌脂多糖 (lipopolysaccharide,L PS)对 NIH 3T3细胞增生、胞内游离钙及 c AMP浓度的影响。　方法 :以中性红比色法检测细胞生长 ,酚试剂法检测细胞蛋白质合成 ,并动态检测 L PS对胞内游离钙和 c AMP浓度的影响。　结果 :1微量 L PS可促进细胞生长及蛋白质合成 ;2 L PS作用后 3～ 5 min可使胞内游离钙浓度升高 ,作用 1 m in后使 c AMP浓度升高 ,并保持较高水平。　结论 :胞内游离钙 ([Ca2 ]i)及 c AMP是 L PS对 NIH3T3细胞作用过程中重要的信使分子     

美国国立健康研究院(NIH)资助的针灸临床研究内容与特点

近年来,美国国立健康研究院(National Institute of Health)对不少针灸临床研究进行了资助。在所资助的60项针灸临床研究中,美国本土的研究有39项,加拿大2项,欧洲7项,中东4项,东南亚8项,中国大陆的复旦大学有2项。有些与手术后或化疗后的病症有关,如幻肢痛,结肠切除术后、化疗后的慢性疲乏、防止放疗后的口腔干燥,减轻手术后的伤口疼,减轻放疗或化疗后的恶心呕吐,减轻手术后的肠梗阻等;有些与疼痛有关,如关节炎、癌症、手术后的疼痛管理等;有与心理精神疾病相关的,如儿童的孤独症,成人的药物滥用等;也有与妇女疾病有关的,如痛经、非周期性乳腺疼痛、生产过程中的生产延迟、生产后会阴修补术引起的疼痛、乳腺炎、妇女更年期以及乳腺癌后的潮热等都纳入了针灸临床研究的范围。与早期只注重于疼痛管理或癌症后的胃肠道反应相比,这些研究项目更深入更广泛。NIH资助的针灸临床研究有以下特点:①规模较小。国内的许多针灸临床往往规模较美国的研究要大。但近年来一些欧洲国家的临床研究参与的病例数就超过了国内一些临床研究项目。②设计严谨。由于NIH的针灸临床研究的研究对象是针灸疗法,在研究的报告中很少提及所用穴位或穴位配合。但大部分的研究都会在纳入或排除标准中注明受试者没有接触过针灸,因为往往在安慰组或假针灸组里,采用假刺或仅仅浅刺,受试者不可能有类似针灸得气的感觉。NIH研究设计的一个优点是随访周期可长达数月甚至数年。③立题新颖。总的来讲,NIH的针灸临床研究项目肯定没有国内的多和广,但它所涉及的领域,有些在国内还是空白。④实用性强。西方人往往是在常规或传统的治疗方法无效的情况下才会想到使用针灸的,在许多疾病如疼痛、癌症、艾滋病、糖尿病或吸毒(药物滥用),会求助于替代医学中的针灸疗法。因而,NIH只会选择那些实用性很强,能切实帮助解决问题的研究进行资助。⑤着重安全。美国NIH对于所有医学治疗的态度可能与国内有所不同,安全性是一个首要的而且是决定性的因素。几乎所有的针灸临床研究都需经过预试验(pilot),设立纳入或排除标准时一定要按照常规医疗的规范来进行,可以避免许多法律上的麻烦。     

Changes in the microvasculature with age

The microvasculature of various organs of the rat and of the mesentery of the cat were examined for histochemical changes as a function of age, using the periodic acid-Schiff (PAS) reaction. Arterioles, minute arteries, and nonmuscular venules were histochemically unchanged to approximately 17 months of age in the rat and 8 years in the cat. Subsequently, focal areas of PAS-positive material developed in the media of arterioles and small arteries and increased in extent and severity with age. The adventitia of nonmuscular venules normally stains slightly positive due to the mucopolysaccharide coating of collagen fibers. With age this adventitial layer becomes more intensely PAS-positive. In the 26-month-old rat and 19-year-old cat, the media of arterioles and small arteries were extensively hyalinized. Lesions of arteriosclerosis were not present. These observations, in consort with prior observations of others in various mammals, indicate that there is a regular systematic alteration of various elements of the microcirculation with age. A possible relationship between these anatomical changes and tissue exchange is considered.     

The effects of nitroglycerin-methoxamine combination on infarct size in conscious dogs

The effect of nitroglycerin combined with methoxamine in reducing infarct weight was studied in conscious dogs. Ten minutes after permanent left anterior descending (LAD) coronary artery occlusion, 10 dogs received nitroglycerin (450 micrograms bolus IV, then 300 micrograms/min for 4 hours) and methoxamine as needed to maintain blood pressure and heart rate. No dogs in heart failure. Ten control dogs received saline solution. Dogs were sacrificed 3 days later. The region at risk of infarction was delineated by simultaneously perfusing the aortic root with Evans blue and the distal LAD artery with saline solution under equal pressures. Slices of stained hearts were incubated with tetrazolium to identify infarct. Total weight of left ventricle (LV), risk region, and infarct was measured. Nitroglycerin-treated dogs showed no difference from control dogs in infarct weight (26.2 +/- 5.9 gm +/- SE vs 27.7 +/- 5.6 gm), percent risk region/LV (36.0 +/- 1.4% vs 37.9 +/- 3.1%), or present infarct/LV (23.5 +/- 5.2% vs 24.8 +/- 4.9%). In a subgroup with risk region/LV less than or equal to 35%, nitroglycerin reduced infarct weight by 45% (8.8 +/- 8.5% vs 15.9 +/- 7.9%), percent infarct/LV by 49% (7.1 +/- 6.8% vs 13.8 +/- 6.6%), and percent infarct/risk region by 41% (23.0 +/- 22.0% vs 38.9 +/- 15.9%). Because of the small number of dogs in the study, differences were not significant. In dogs with risk region/LV greater than 35%, nitroglycerin had no effect. Thus, in dogs without overt heart failure, nitroglycerin may salvage ischemic tissue within small areas at risk of infarction, but the results are not definitive. However, our results clearly demonstrate that in the absence of failure, nitroglycerin does not reduce the size of large infarcts.