响应面法优化淡竹叶总黄酮的大孔树脂纯化工艺

目的:探讨响应面法优化淡竹叶总黄酮大孔树脂纯化工艺。方法:比较四种大孔树脂对淡竹叶总黄酮的吸附和解吸性质,筛选合适的树脂,采用响应面法优化纯化工艺。结果:通过实验数据分析,较佳纯化工艺条件为上样液质量浓度0.12 g/m L,乙醇体积分数75%,洗脱液用量6BV。结论:通过响应面法优选的淡竹叶总黄酮大孔树脂纯化工艺稳定可行,预测性好。     

中药淡竹叶的化学成分研究(II)

目的研究淡竹叶 (LophatherumgracileBrongn .)的化学成分。方法色谱方法分离化学成分 ,波谱技术及理化常数鉴定结构。结果分离鉴定了 4个化合物 ,牡荆素 ( 1 )、胸腺嘧啶 ( 2 )、香草酸( 3)和腺嘌呤 ( 4 )。结论均为首次从该属植物中分离得到     

Expansion of the Central Hindpaw Representation Following Fetal Forelimb Removal in the Rat

We provide evidence that prenatal removal of a rat forelimb results in both a disruption of the anatomical representation which would normally correspond to the forepaw and in an enlargement of the adjacent hindpaw representation in the brainstem and cortex. This enlargement, which in some cases is as much as 100%, only occurs following complete forelimb amputation on embryonic day 17 (E17) or earlier. This coincides with the age at which forepaw afferents first arrive in the brainstem, suggesting to us that the expansion is permitted in part because ingrowing hindpaw afferents are in the presence of cuneate cells which have never been previously innervated; in animals older than E17, the expansion is prohibited by either an intrinsic age-dependent change in the cuneate cells, or a change imposed upon them by forelimb afferents. The number of cells in dorsal root ganglia subserving the expanded hindpaw areas does not differ from normal suggesting that the expansion of hindpaw territory within the brainstem reflects an increased terminal arborization by a normal complement of primary hindpaw afferents. We interpret the cortical enlargement to be an upstream reflection of the brainstem events. In cortex, the enlargement seems to result from an invasion of the dysgranular cortex by thalamic afferents arising from the ventral posterior nucleus.     

Role of nerve growth factor in the adult dorsal root ganglia neuron and its response to injury

The response of dorsal root ganglia (DRG) neurons to NGF deprivation and to axotomy was examined in adult guinea pigs. The success of NGF deprivation by means of an autoimmune approach was monitored by the measurement of serum antibody titer levels against guinea pig NGF with the standard bioassay for NGF activity. That the antibody produced NGF deprivation was confirmed by histologic evidence of neuronal atrophy and apparent cell loss in sections of the superior cervical ganglia (SCG) and by marked decreases (65-80%) of SCG neurotransmitter-synthesizing enzyme activity levels. By using the autoimmune approach a new source of guinea pigs was found which consistently produced high titers of cross-reacting anti-NGF antibodies. Experiments were designed to examine the response of the sensory neuron to injury while chronically deprived of NGF. Total neuronal counts in the sixth lumbar DRG 98 days after sciatic nerve crush showed no difference between NGF-deprived and control ganglia. Measurement of the size spectrum of DRG neurons showed evidence of atrophy of the NGF-deprived neurons in both the uninjured and axotomized side compared to respective controls. The mean volume of uninjured sensory neurons measured in the NGF-deprived guinea pigs was decreased 27.7% (P less than .05) compared with that of control guinea pigs. The degree of regeneration 6 days following a nerve crush was the same in NGF-deprived sensory neurons and in controls when measured by the "pinch test" and by isotope-labeled axonal transport studies.(ABSTRACT TRUNCATED AT 250 WORDS)     

Modulation of Neuropathic Pain by Galanin and Neuropeptide Y at the Level of the Medulla in Rats

This study was conducted to examine the role of galanin and neuropeptide Y (NPY) in the modulation of neuropathic pain at the level of the medulla. Under pentobarbital anesthesia, Sprague-Dawley rats were subjected to neuropathic surgery. Intracisternal injections of galanin and NPY were performed 2 weeks after nerve injury and mechanical allodynia was monitored. In an electrophysiological experiment, rats were reanesthetized with urethane and the responses of gracile nucleus neurons to mechanical stimulation were observed. Galanin and NPY were applied microiontophoretically. Intracisternally administered NPY reduced neuropathic pain behaviors in a dose-dependent manner. High doses of galanin inhibited neuropathic pain behaviors. Iontophoretically ejected galanin and NPY inhibited responses of gracile nucleus neurons to mechanical stimulation. These results suggest that galanin and NPY play a role in modulating neuropathic pain in the gracile nucleus of the medulla.     

经典名方竹叶石膏汤的物质基准量值传递分析

目的建立竹叶石膏汤(Zhuye Shigao Decoction,ZSD)物质基准的HPLC特征图谱及指标成分含量测定方法,并结合化学模式识别法进行评价,探寻其质量传递规律。方法制备20批ZSD物质基准,建立HPLC特征图谱,明确共有峰归属,测定全方出膏率、指标成分异荭草苷、人参皂苷Rg1、人参皂苷Re、人参皂苷Rb1、甘草苷和甘草酸的含量及转移率,对物质基准进行量值传递分析。结果 20批ZSD物质基准特征图谱的相似度均大于0.90,共确定了21个特征峰,分别来自方中淡竹叶(6个峰)、麦冬(6个峰)、半夏(3个峰)、甘草(6个峰)4个药味;化学模式识别法将20批样品分为4类;各指标成分从饮片到物质基准的转移率分别为异荭草苷31.94%～50.91%,甘草苷35.77%～62.55%,甘草酸13.09%～22.63%,人参皂苷Rg1 57.28%～83.95%,人参皂苷Re 42.21%～72.27%,人参皂苷Rb1 38.19%～64.57%;出膏率为16.99%～27.06%。结论采用特征图谱、多指标含量测定以及化学模式识别法对ZSD物质基准进行量值传递分析,该方法科学合理,可为后续制剂开发提供参考。     

Lateral Corticospinal Tract Damage Correlates With Motor Output in Incomplete Spinal Cord Injury

Objective

To investigate the relationship between spinal cord damage and specific motor function in participants with incomplete spinal cord injury (iSCI).

The centrally projecting Edinger–Westphal nucleus—I: Efferents in the rat brain

The oculomotor accessory nucleus, often referred to as the Edinger–Westphal nucleus [EW], was first identified in the 17th century. Although its most well known function is the control of pupil diameter, some controversy has arisen regarding the exact location of these preganglionic neurons. Currently, the EW is thought to consist of two different parts. The first part [termed the preganglionic EW—EWpg], which controls lens accommodation, choroidal blood flow and pupillary constriction, primarily consists of cholinergic cells that project to the ciliary ganglion. The second part [termed the centrally projecting EW—EWcp], which is involved in non-ocular functions such as feeding behavior, stress responses, addiction and pain, consists of peptidergic neurons that project to the brainstem, the spinal cord and prosencephalic regions. However, in the literature, we found few reports related to either ascending or descending projections from the EWcp that are compatible with its currently described functions. Therefore, the objective of the present study was to systematically investigate the ascending and descending projections of the EW in the rat brain. We injected the anterograde tracer biotinylated dextran amine into the EW or the retrograde tracer cholera toxin subunit B into multiple EW targets as controls. Additionally, we investigated the potential EW-mediated innervation of neuronal populations with known neurochemical signatures, such as melanin-concentrating hormone in the lateral hypothalamic area [LHA] and corticotropin-releasing factor in the central nucleus of the amygdala [CeM]. We observed anterogradely labeled fibers in the LHA, the reuniens thalamic nucleus, the oval part of the bed nucleus of the stria terminalis, the medial part of the central nucleus of the amygdala, and the zona incerta. We confirmed our EW–LHA and EW–CeM connections using retrograde tracers. We also observed moderate EW-mediated innervation of the paraventricular nucleus of the hypothalamus and the posterior hypothalamus. Our findings provide anatomical bases for previously unrecognized roles of the EW in the modulation of several physiologic systems.     

淡竹叶的化学成分研究

目的研究淡竹叶的化学成分。方法采用系统提取,柱层析方法分离,经理化性质和波谱技术确定所得化合物的结构。结果分离得到6个化合物,鉴定为三十九烷酸(Ⅰ),正三十二烷醇(Ⅱ),三十一烷酸(Ⅲ),对羟基苯甲醛(Ⅳ),反式对香豆酸(Ⅴ),日当药黄素(Ⅵ)。结论化合物Ⅰ～Ⅲ,Ⅴ和Ⅵ均为首次从该植物中分离得到。     

The neuronal adhesion protein D2 in differentiating aggregates of brain cells

The preparation and maintenance of a novel slice of the rat gracile nucleus is described. The slice includes both gracile nuclei as well as an intact afferent input from the dorsal columns. Extracellular recording revealed that a compound tract action potential (CAP) could be recorded from the gracile nucleus following stimulation of the ipsilateral dorsal column. The CAP was followed by slower field potentials which are thought to be dependent on synaptic activity. Four consequences of stimulating the dorsal columns were observed: (1) a subsequent CAP was conducted more rapidly along the afferents whether it travelled in an orthodromic or antidromic direction; (2) the amplitude of a subsequent orthodromic CAP was reduced; (3) the amplitude of a subsequent submaximal antidromic CAP was increased; and (4) a slow positive potential could be recorded from the dorsal columns. All 4 phenomena had comparable time-courses and were similarly sensitive to agents which reduce synaptic transmission. Pharmacological evidence indicated that all 4 phenomena were mediated by GABA. It is suggested that a GABA-mediated depolarization of the gracile afferents can be evoked in this slice.