Chronic Δ9-Tetrahydrocannabinol in rats: Effect on social interactions,mouse killing,motor activity,consummatory behavior,and body temperature

Behavioral and physiologic effects of daily administration of ⁹-tetrahydrocannabinol (THC) were assessed over a 60-day period, investigating different dose levels (10, 20, 50 mg/kg), routes of administration (i.p., p.o.), drug vehicles [5%–18% propylene glycol(PG)/1% Tween 80-saline; sesame oil], and rat strains (Sprague-Dawley, Wistar, Long-Evans, Fischer). All THC-treated rats showed compulsive motor routines (i.e., forepaw treading, rhythmic jaw movements, prolonged head grooming, and biting of cage wires) after 3–4 weeks. Whether maintained on a restricted feeding regimen or not, three was no evidence for increased aggressive behavior between cagemates in any of the treatment groups. Mouse killing was induced in 70%–75% of all Sprague-Dawley (i.p., PG/Tween 80-saline vehicle) and Fischer rats (p.o., sesame oil vehicle), but not in the other THC-treated groups. Rearing activity was greatly decreased in all THC-treated groups throughout the treatment period. Food and water intake decreased by approximately 40% during the first 2–6 days of THC administration. Growth rate was reduced for the entire treatment period in THC-treated rats. THC decreased rectal temperature on the 1st day, and also on the 2nd day in Fischer rats receiving the drug in sesame oil, but not thereafter. This pattern of effects shows that tolerance develops rapidly to THC's effects on body temperature and consummatory behavior, but not to changes of certain motor activities.     

The architecture of the colour centre in the human visual brain: new results and a review

We have used the technique of functional magnetic resonance imaging (fMRI) and a variety of colour paradigms to activate the human brain regions selective for colour. We show here that the region defined previously [Lueck et al. (1989) Nature, 340, 386-389; Zeki et al. (1991) J. Neurosci., 11, 641-649; McKeefry & Zeki (1997) Brain, 120, 2229-2242] as the human colour centre consists of two subdivisions, a posterior one, which we call V4 and an anterior one, which we refer to as V4alpha, the two together being part of the V4-complex. The posterior area is retinotopically organized while the anterior is not. We discuss our new findings in the context of previous studies of the cortical colour processing system in humans and monkeys. Our new insight into the organization of the colour centre in the human brain may also account for the variability in both severity and degree of recovery from lesions producing cerebral colour blindness (achromatopsia).     

Generation and propagation of 4-AP-induced epileptiform activity in neonatal intact limbic structures in vitro

We examined the generation, propagation and pharmacology of 4-aminopyridine (4-AP)-induced epileptiform activity (EA) in the intact interconnected limbic structure of the newborn (P0-7) rat in vitro. Whole-cell recordings of CA3 pyramidal cells and multisite field potential recordings in CA3, CA1, dentate gyrus, and lateral and medial entorhinal cortex revealed 4-AP-induced EA as early as P0-1. At this age, EA was initiated in the CA3 region and propagated to CA1, but not to the entorhinal cortex. Starting from P3-4, EA propagated from CA3 to the entorhinal cortex. Along the CA3 septo-temporal axis, EA arose predominantly from the septal pole and spread towards the temporal site. Whereas the onset of 4-AP-induced EA decreased with age from 21.2 +/- 1.6 min at P0-1 to 4.7 +/- 0.63 min at P6-7, the seizure duration increased in the same age groups from 98 +/- 14 s to 269.4 +/- 85.9 s, respectively. The EA was blocked by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) but not by DL-2-amino-5-phosphonovaleric acid (APV), (+)-MK-801 hydrogen maleate (MK-801) or (+/-)-alpha-methyl-4-carboxyphenylglycine (MCPG), suggesting that they were mediated by alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA)/kainate receptor activation. We conclude that: (i) the septal pole of the hippocampal CA3 region plays a central role in the generation of EA in the neonatal limbic system; and (ii) AMPA/kainate receptor-mediated EA can be generated in CA3 already at birth. Therefore, the recurrent collateral synapses and circuits required for the generation of EA are developed earlier than previously suggested on the basis of studies on hippocampal slices.     

Basic properties of an inositol 1,4,5-trisphosphate-gated channel in carp olfactory cilia

In addition to the activation of cAMP-dependent pathways, odorant binding to its receptor can lead to inositol 1,4,5-trisphosphate (InsP3) production that may induce the opening of plasma membrane channels. We therefore investigated the presence and nature of such channels in carp olfactory cilia. Functional analysis was performed by reconstitution of the olfactory cilia in planar lipid bilayers (tip-dip method). In the presence of InsP3 (10 microM) and Ca2+ (100 nM), a current of 1.6 +/- 0.1 pA (mean +/- SEM, n = 4) was measured, using Ba2+ as charge carrier. The I/V curve displayed a slope conductance of 45 +/- 5 pS and a reversal potential of -29 mV indicating a higher selectivity for divalent cations. This current was characterized by two mean open times (3.0 +/- 0.4 ms and 42.0 +/- 2.6 ms, n = 4) and was strongly inhibited by ruthenium red (30 microM) or heparin (10 microg/mL). Importantly, the channel activity was closely dependent on the Ca2+ concentration, with the highest open probability (Po) at 100 nM Ca2+ (Po = 0.50 +/- 0.02, n = 4). Po is lower at both higher and lower Ca2+ concentrations. A structural identification of the channel was attempted by using a large panel of antibodies, raised against several InsP3 receptor (InsP3R)/Ca2+ release channel isoforms. The type 1 InsP3R was detected in carp cerebellum and whole brain, while a lower molecular mass InsP3R, which may correspond to type 2 or 3, was detected in heart, whole brain and the soma of the olfactory neurons. None of the antibodies, however, cross-reacted with olfactory cilia. Taken together, these results indicate that in carp olfactory cilia an InsP3-dependent channel is present, distinct from the classical InsP3Rs localized on intracellular membranes.     

One-year prevalence and incidence of depression among first-year university students in Japan: a preliminary study

A structured interview was used to examine the 1-year incidence and prevalence of depression among 116 first-year university students. While 24 of the subjects (20.7%) met the Diagnostic and Statistical Manual of Mental Disorders 4th ed. (DSM-IV) criteria for Major Depressive Episode (MDE), 62 (53.4%) met the Diagnostic and Statistical Manual of Mental Disorders 3rd ed. Revised (DSM-III-R) criteria for MDE, and 27 (23.3%) also met the Research Diagnostic Criteria (RDC) for Major Depressive Disorder (MDD) for the 12 months prior to the interview. Moreover, 23 of the subjects (19.8%) had onset of the DSM-IV criteria for MDE, 54 (46.6%) had onset of the DSM-III-R criteria for MDE, 24 (20.7%) had onset of the RDC for MDD, during the same time period. These high rates of depression may be explained by the students' difficulties in and by their readjustment after entering university.     

茵陈提取液对实验性动物肝损伤的作用

目的　研究茵陈提取液对实验性肝损伤的作用。 方法　 用茵陈提取液连续给小鼠灌胃 7d后 ,采用四氯化碳 (CCL4 )腹腔内注射造成小鼠急性肝损伤 ,造型 2 0h后摘除眼球取血 ,测ALT、AST、ALP、TP、G、A等指标 :给大鼠每周二次皮下注射 10 %CCL4油液 0 .5ml/ 10 0g ,造成慢性肝损伤 ,于中毒第三个月初起开始 ,每日用茵陈提取液连续给大鼠灌胃一个月 ,于末次给药 2 4h眶静脉取血 ,分离血清 ,AT、AST、总蛋白、白蛋白、白蛋白 /球蛋白 (A/G)等指示。 结果　CCL4造成小鼠急性肝脏损伤 ,出现明显肝功能异常 ,茵陈提取液治疗组小鼠各项指标较CCL4模型组均有所降低 ,但差异无显著性意义 (P >0 .0 5 ) ;在CCL4所致大鼠慢性肝损伤模型中 ,茵陈提取液治疗组可显著地降低大鼠由CCL4造成的AST活性升高 ,与模型组比较 ,P <0 .0 1。 结论　 茵陈提取液对CCL4所致大鼠慢性肝损伤有较好的治疗作用 ,但对CCL4造成小鼠急性肝伤模型没有保护作用。     

紫草大黄合剂对四氯化碳致小鼠急性肝损伤保护作用的观察

目的：观察不同浓度的紫草大黄合剂对四氯化碳（CCl4）致小鼠急性肝损伤的保护作用。方法：采用腹腔注射CCl4致小鼠急性肝损伤为模型，测定高低剂量的紫草大黄合剂对肝损伤ALT、AST值，同时对肝组织进行病理组织检查。结果：高剂量紫草大黄合剂同联苯双酯一样能够明显降低CCl4致小鼠肝损伤血清ALT、AST值升高（P＜0．01），减轻CCl4对肝脏细胞的病理损伤。结论：紫草大黄合剂对CCl4致急性肝损伤具有一定的保护作用。     

面口合谷收的形态学基础

目的：探讨合谷穴与口面部联系的形态学基础。方法：采用荧光素单标记和双标记法，将荧光素碘化丙啶（PI）和双苯甲亚胺（Bb)分别注入“合谷”穴区和“四白”穴区，取同侧脊神经节颈1-颈8，胸1-胸2，颈上，中，下交感节及三叉神经半月节，荧光显微镜下观察计数。结果：在脊神经节颈5-颈8观察到大量PI单标记细胞，主要分布于颈6-颈7，在三叉神经半月节也可见大量Bb单标记细胞，另外在三叉神经半月节可见少量PI-Bb以标记细胞，占标记细胞的4.5%。结论：三叉神经半月节有向“合谷”穴和“四白”穴的分支投射，这可能是“面口合谷收”的形态学基础。     

重肌灵对EAMG大鼠血清IL-4、IFN-γ水平的影响

观察中药复方重肌灵对EAMG大鼠血清IL－4、IFN－γ调节作用。方法：采用N2AchR加等量福氏完全佐剂，多次免疫Lewis大鼠，复制EAMG模型，并对模型进行评价。动物随机分为正常组、佐剂组、模型组、地塞米松组和重肌灵组。采用ELISA法观察各组动物血清AchRab、IL－4、INF－γ水平。结果：重肌灵、地塞米松组大鼠血清AchRab滴度、IL－4、IFN－γ水平明显降低，与模型组比较，有非常显著性差异（P＜0.01）。但两治疗组之间无显著性差异（P＞0.05）。结论：重肌灵具有良好的防治EAMG效果，可能是通过下调血清IL－4、IFN－γ，抑制AchRab产生，而起到治疗作用。     

培补肝肾复方对1-甲基-4-苯基吡啶离子致多巴胺能神经元损伤的影响

目的　观察 1-甲基 - 4 -苯基吡啶离子 (MPP+ )对原代培养的新生鼠中脑多巴胺能神经元数目和形态的改变 ,并探讨培补肝肾复方对多巴胺能神经元的保护作用和机制。方法　采用血清药理学的方法 ,观察培补肝肾复方含药血清对MPP+ 损伤多巴胺能神经元细胞存活时间、存活率的影响及细胞形态学的变化。结果　等效剂量培补肝肾中药复方含药血清(灌胃剂量为 3g/kg)可延长MPP+ 损伤多巴胺神经细胞的存活时间 ,提高细胞的存活率。结论培补肝肾复方中药血清对体外培养MPP+ 损伤的多巴胺能神经细胞具有保护作用。