褪黑素对锰致小鼠纹状体多巴胺能系统障碍的影响

目的研究锰对小鼠纹状体多巴胺系统的影响以及褪黑素(MLT)的干预作用,为锰中毒机制的研究提供理论依据。方法小鼠70只,随机均分为(1)对照组、(2)氯化锰组、(3)低MLT+氯化锰组、(4)中MLT+氯化锰组、(5)高MLT+氯化锰组。第1、2组皮下注射(sc)0.9%氯化钠,第3~5组sc给予1.25、2.5和5 mg/kg MLT;2 h后,第1组腹腔注射(ip)0.9%生理盐水,第2~5组ip给予50 mg/kg Mn Cl2。每天1次,连续2周。ELISA检测黑质内多巴胺(DA)含量,免疫组织化学及western blotting检测DAT和DRD1的蛋白水平。结果与对照组相比,氯化锰组上述指标均出现了不同程度的降低,纹状体DA含量显著降低69.97%(P0.01),免疫组织化学结果显示DAT和DRD1积分光密度分别下降62.54%和66.61%(P0.01),DAT和DRD1的蛋白水平均明显降低;与氯化锰组相比,随着MLT浓度的升高,DA含量、DAT和DRD1表达量逐渐上升,并呈剂量-效应关系。结论过量锰暴露可导致纹状体多巴胺系统的损伤,褪黑素可以拮抗锰所致的上述变化。     

听障儿童会话流畅度研究

目的：探讨提高听障儿童会话流畅度的有效方法。方法采用调查研究法对20名听障儿童会话表现进行分析。结果会话流畅度与流畅度问卷得分存在显著相关。听障儿童平均说话次数、平均会话轮替长度（Mean length of turn,MLT）及MLT比率分别为7.8、8.3、.42。会话流畅度与年龄、年级、性别、裸耳听阈及助听听阈没有显著相关。结论预测分析显示，会话流畅度问卷能够预测MLT及MLT比率，因此在听障儿童康复训练中应强调会话策略的教学，以期提升会话流畅度。     

褪黑素对慢性间歇性缺氧心肌的保护作用

褪黑素（melatonin,MLT）是由松果体分泌的一种重要的吲哚胺类激素,化学名称N-乙酰基-5-甲氧基色胺（N—acetyl-5-methoxytrypatmine）。MLT具有多种生理功能,除具有调节生物的昼夜节律、提高免疫力、改善睡眠、抗炎、抗氧化、抗肿瘤、抗衰老外,还影响心血管系统,有抗高血压、调节血脂代谢、抗心肌细胞损伤及对血管内皮保护的作用。本文就MLT生物学作用及对慢性间歇性缺氧性心肌保护作用进行简要综述。     

Anxiolytic effects of the melatonin MT2 receptor partial agonist UCM765: Comparison with melatonin and diazepam

Melatonin (MLT) is a neurohormone known to be involved in the regulation of anxiety. Most of the physiological actions of MLT in the brain are mediated by two high-affinity G-protein-coupled receptors, denoted MT₁ and MT₂. However, the particular role of these receptors in anxiety remains to be defined. Here we used a novel MT₂-selective partial agonist, UCM765 to evaluate the involvement of MT₂ receptors in anxiety. Adult male rats were acutely injected with UCM765 (5–10–20 mg/kg), MLT (20 mg/kg) or diazepam (DZ, 1 mg/kg). Anxiety-related behaviors were assessed in the elevated plus maze test (EPMT), novelty suppressed feeding test (NSFT) and open field test (OFT). UCM765 at the dose of 10 mg/kg showed anxiolytic-like properties by increasing the time spent in the open arm of the EPMT, and by reducing the latency to eat in a novel environment in the NSFT. In the EPMT, animals treated with UCM765 (10 mg/kg) or MLT (20 mg/kg) spent more time in the open arms compared to vehicle-treated animals, but to a lesser extent compared to DZ (1 mg/kg). In the NSFT, all treatments similarly decreased the latency to eat in a novel environment compared to vehicle. UCM765 and MLT did not affect the total time and the number of entries into the central area of the OFT, but unlike DZ, did not impair locomotion. The anxiolytic effects of UCM765 and MLT in the EPMT and the NSFT were blocked using a pre-treatment with the MT₁/MT₂ antagonist luzindole (10 mg/kg) or the MT₂ antagonist 4P-PDOT (10 mg/kg). These results demonstrated, for the first time, the anxiolytic properties of UCM765 and suggest that MT₂-receptors may be considered a novel target for the development of anxiolytic drugs.     

Somatosensory systems and the milk-ejection reflex in the rat. I. Lesions of the mesencephalic lateral tegmentum disrupt the reflex and damage mesencephalic somatosensory connections

Bilateral electrolytic lesions and unilateral tracer injections were performed in lactating rats in order to study the participation of the mesencephalic lateral tegmentum in the milk-ejection reflex. The release of oxytocin was detected as a rise in intramammary pressure during each milk ejection. In animals with lesions, the lateral part of the deep grey layers of the superior colliculus, the intercollicular area and the rostromedial portion of the external nucleus of the inferior colliculus were destroyed. The mesencephalic lateral tegmentum of animals in which the milk-ejection reflex was blocked sustained a larger damage than in rats where the frequency of the milk-ejection response was only slowed down. Solutions of True Blue, horseradish peroxidase or horseradish peroxidase coupled to wheat germ agglutinin were injected in the mesencephalic lateral tegmentum of rats with and without lesions. Retrogradely labelled cells were found in several nuclei of the somatosensory pathways: the principal sensory and spinal parts of the trigeminal complex, the cuneate and gracile nuclei, the lateral cervical nucleus and the nucleus proprius of the spinal cord. Labelled cells were also found in the ventral nucleus of the lateral lemniscus, the ventral parabrachial nucleus, the gigantocellular reticular nucleus, the lateral nucleus of the substantia nigra, the prerubral nucleus of the thalamus, the hypothalamic ventromedial nucleus, the zona incerta and in the anterior and lateral hypothalamic areas. Labelled fibres and "terminal-like" labelling were found in the anterior pretectal area, in the thalamic parafascicular nucleus, in the posterior nucleus and the ventroposterior complex, in the zona incerta and in the fields of Forel, but none were observed in the supraoptic or paraventricular nuclei. Injections made in the area of the lateral cervical nucleus and in the cuneate and gracile nuclei labelled fibres and "terminal-like" fields in the external nucleus of the inferior colliculus, the intercollicular area, the deep grey layers of the superior colliculus and in the mesencephalic lateral tegmentum. After injections in the posterior nucleus and ventroposterior complex of the thalamus, retrogradely labelled cells were found in the lateral tegmentum, the intercollicular area and the external nucleus of the inferior colliculus. These results indicate that bilateral lesioning of the mesencephalic lateral tegmentum, which disrupts the milk-ejection response, could damage somatosensory projections originating from the dorsal horn of the spinal cord, the lateral cervical nucleus, the dorsal column nuclei and the sensory and spinal trigeminal nuclei.(ABSTRACT TRUNCATED AT 400 WORDS)     

Role of the nonspecific thalamus in amygdaloid kindling

The effects of lesions of the inferior thalamic peduncle, rostral thalamic nuclei, dorsomedial nucleus, and ventroanterior nucleus on the developing and established kindled amygdaloid convulsion were examined. Lesions of these regions made before kindling produced a slight but nonsignificant facilitation in the rate of primary-site seizure development. However, lesions of these same regions made after primary-site kindling resulted in a transient but significant disruption in subsequent seizures. These data suggest that the nonspecific thalamic projection system does not critically participate in amygdaloid kindling. Furthermore, because previous studies established a major role for the nonspecific thalamus in partial epilepsy of neocortical origin, we suggest that the mechanisms that underlie seizures of neocortical origin may differ from those of limbic origin.     

褪黑素通过抑制ROS改善胰岛素抵抗HepG2细胞糖代谢

目的探讨褪黑素（MLT）对胰岛素抵抗（IR）HepG2细胞葡萄糖代谢的影响及机制。方法培养HepG2细胞,高糖高胰岛素（25mmol／L葡萄糖、1μmol／L胰岛素）诱导24h,建立IR细胞模型并给予MLT（1nmol／L,10nmol／L）处理。葡萄糖氧化酶法、蒽酮法和荧光探针法检测HepG2细胞的糖摄取、糖原含量及活性氧（ROS）产率。结果HGI孵育HepG2细胞24h后,细胞的葡萄糖摄取及糖原含量明显减少（P〈0．01）,ROS产率显著增加（P〈0．01）;而MLT处理增加了IR细胞葡糖糖的摄取（P〈0．01）和糖原合成（P〈0．05）,降低ROS的水平（P〈0．01）。结论MLT可能通过抑制ROS的生成而改善氧化应激,从而促进胰岛素抵抗HepG2细胞葡萄糖的摄取和利用、增强其胰岛素敏感性。     

乳酸菌素片联合莫沙必利治疗功能性消化不良的临床研究

目的探讨乳酸菌素片联合莫沙必利治疗功能性消化不良的临床研究。方法选取2016年6月—2018年6月南京鼓楼医院集团宿迁市人民医院收治的100例功能性消化不良患者,随机分成对照组和治疗组,每组各50例。对照组口服枸橼酸莫沙必利片,5mg/次,3次/d。治疗组在对照组治疗基础上口服乳酸菌素片,2片/次,3次/d。两组均连续治疗4周。观察两组的临床疗效,比较两组治疗前后症状积分、功能性消化不良生存质量量表(FDDQL)评分、胃排空率及胃肠激素的变化情况。结果治疗后,对照组和治疗组的总有效率分别是80.0%、94.0%,两组比较差异具有统计学意义(P0.05)。治疗后,两组早饱感评分、中上腹烧灼感评分、中上腹痛评分、餐后饱胀不适评分及总分均显著降低,同组治疗前后比较差异有统计学意义(P0.05);治疗后,治疗组这些症状评分均显著低于对照组,两组比较差异具有统计学意义(P0.05)。治疗后,治疗后两组日常活动评分、饮食评分、不适评分、疾病控制评分、忧虑评分、睡眠评分、健康感觉评分、压力评分和总评分均显著升高,同组治疗前后比较差异有统计学意义(P0.05);治疗后,治疗组FDDQL各领域评分显著高于对照组,两组比较差异具有统计学意义(P0.05)。治疗后,两组胃排空率、胃动素(MLT)均较治疗前显著增加,但血浆胃泌素(GAS)显著降低,同组治疗前后比较差异有统计学意义(P0.05);治疗后,治疗组胃排空率、MLT水平显著高于对照组,GAS水平显著低于对照组,两组比较差异具有统计学意义(P0.05)。结论乳酸菌素片联合莫沙必利治疗功能性消化不良具有较好的临床疗效,可明显减轻患者症状,正性调节胃肠激素分泌,提高生活质量,具有一定的临床推广应用价值。