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1.
Summary The influence of cholinergic and dopaminergic agents on the acquisition of a passive avoidance response in the rat is demonstrated. Trifluoperazine (0.12 mg/kg), a dopamine antagonist, inhibited task acquisition when present during training or later, during consolidation, at the 10–12 h posttraining period and at no other intervening time point. Induction of amnesia was dose-dependent and was not apparent when the dose exceeded 0.12 mg/ kg. This effect appears to be due to an increase in dopamine release through presynaptic receptor antagonism as similar results could be obtained by the administration of apomorphine (0.5 mg/kg), a dopamine agonist, and this effect could be antagonized by the D 1 receptor selective antagonist SCH-23390. Scopolamine (0.15 mg/kg), a muscarinic antagonist, impaired acquisition of the passive avoidance response when administered during training and, separately, at the 6 h post-training period. This could not be attributed to presynaptic antagonism as oxotremorine (0.2 mg/kg), a muscarinic agonist, had no amnesic action. Administration of apomorphine or scopolamine during training and at the appropriate post-training period prevented subsequent paradigm-specific increases of neural cell adhesion molecule sialylation state in hippocampal immunoprecipitates obtained at 24 h after task acquisition and 4 h following intraventricular infusion of the labelled sialic acid precursor — N-acetyl-D-mannosamine. Oxotremorine alone did not influence neural cell adhesion molecule sialylation state. These observations provide further evidence of a regulatory role for neural cell adhesion molecule sialylation state in information storage processes.Abbreviations
NCAM
neural cell adhesion molecule
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RSA
relative specific activity
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SDS-PAGE
sodium dodecyl sulphate polyacrylamide gel electrophoresis
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TCA
trichloroacetic acid
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TFP
trifluoperazine 相似文献
2.
Paavo Riekkinen Jr. Jouni Sirvi Pekka Jkl Maria Mazurkiewicz Antti Valjakka Minna Riekkinen Paavo Riekkinen 《Brain research bulletin》1991,27(2):287-289
Quisqualic acid NBM lesions had no effect on water maze performance, but slightly impaired passive avoidance acquisition. GammavinylGABA treatment alone had no effect on the passive avoidance and water maze performance, but aggravated acquisition deficit in rats subjected to NBM lesioning. However, gammavinylGABA-treated NBM-lesioned rats reached control level of performance. 相似文献
3.
Neuronal plasticity can manifest itself in alterations in the sensitivity of memory to the effects of drugs. After the production of a brain lesion, the memory processing of a passive-avoidance task in mice gradually becomes sensitive to the effect of morphine, i.e., an improvement in retention performance is seen after 6 weeks, but not after 1 or 2 weeks. The results presented demonstrate that, even if they lead to no discernible changes in behaviour, plastic processes can still be detected by means of behavioural tests. 相似文献
4.
用高价人抗HBs在人体内诱导产生抗HBs 总被引:2,自引:0,他引:2
本文探讨用外源性人抗HBs在人体通过免疫网络诱导产生自身的抗HBs的可能性。志愿者经多次注射人高价抗HBs(Ab_1)后,体内产生了Ab_2,进而产生出特异性与Ab_1相同的Ab_3;当Ab_3水平升高时,Ab_2水平下降。此结果证实了人体内独特型网络的存在及其活跃的调节功能,表明用于被动免疫的人抗HBs在人体也能通过激活独特型网络产生主动免疫保护作用。此外,本文的结果还提示,注射人抗HBs后,人体内产生的Ab_2可模拟HBsAg,使常规的HBsAg检查出现假阳性结果。 相似文献
5.
Exploratory behavior (GMA) and habituation rate (IH) were studied in an open-field situation in normal and adrenalectomized rats. Following this procedure the rats were subjected to passive avoidance learning (PA). Wide-spreading individual differences were observed in the exploratory behavior and the tendency of habituation of normal rats. As compared to the normal values, either the adrenalectomy which was performed 24 hr, 7 days and 28 days prior to the experiments or the ACTH and hydrocortisone treatment failed to modify the GMA and the IH significantly. An improvement of PA was found in the normal rats following ACTH and hydrocortisone treatment. In the adrenalectomized animals the hydrocortisone proved to be effective, whereas ACTH did not influence PA. No correlation was found between GMA, IH versus PA values and the influence of ACTH and hydrocortisone administration on these parameters. It is concluded that the direction of PA is unpredictable on the basis of the open-field test performed on R-Amsterdam strain of rats, and the effect of ACTH on passive avoidance learning is mediated through the adrenal glands. 相似文献
6.
Giorgio Torelli Eloisa Milla Leonard I. Kleinman Alide Faelli 《Pflügers Archiv : European journal of physiology》1973,342(3):219-230
Summary The relationship between sodium reabsorption and oxygen consumption was studied in an isolated rabbit kidney preparation perfused with blood at 37, 28 and 19° C. When the temperature was lowered from 37° C to 28° C and to 19°C the rate of oxygen consumption and of the maximal P.A.H. excretion (Tm P.A.H.) decreased more than that of sodium reabsorption.TheQ
10 for sodium reabsorption is about 1.8, while that for maximal P.A.H. excretion is 2.5. Some hypothesis on the possible mechanisms of the lowQ
10 of the Na+ reabsorption are forwarded.Preliminary reports have been published [Boll. Soc. Ital. Biol. Sper.43, 1019–1023 (1966) and44, 1784–1787 (1967);45, 860–862 (1969) and45, 863–865 (1969)]. 相似文献
7.
S Hosoi K Shinomiya H Nakano H Mikawa S Harada 《The Journal of allergy and clinical immunology》1985,75(2):320-327
Eight monoclonal anti-human IgG antibodies were fully characterized and evaluated as possible reagents in solid phase radioimmunoassay for quantitating allergen-specific IgG antibody. Four monoclonal antibodies (HG24D, HG2-14, HG2-18, and HG2-25) recognize CH2 domain of human IgG and bind to human IgG fixed to microtiter plate with high affinities. These monoclonal antibodies were more suitable than polyclonal rabbit anti-human IgG antibody in Phadebas RAST for honey bee venom-specific IgG antibody. Nonspecific binding was much lower, and the slopes of standard curves were much steeper. In contrast to polyclonal antibody, the standard curve was hardly influenced by human serum IgG in sample diluent. These advantages of monoclonal antibodies that recognize CH2 domain of human IgG made it possible to quantitate egg white- and Dermatophagoides pteronyssinus-specific IgG antibodies with use of allergen disks prepared for IgE RAST. This property allows a single system to be used for measurement of IgG and IgE antibodies against clinically relevant allergens. 相似文献
8.
Becker W Nasios G Raab S Jürgens R 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,144(4):458-474
When observers step about their vertical axis ("active turning") without vision they dispose of essentially two sources of information that can tell them by how much they have turned: the vestibular cue which reflects head rotation in space and the "podokinesthetic" cue, a compound of leg proprioceptive afferents and efference copy signals which reflects the observer's motion relative to his support. We ask how these two cues are fused in the process leading to the perception of self-displacement during active turning. To this end we compared the performance of observers in three angular navigation tasks which differed with regard to the number and type of available motion cues: (1) Passive rotation, vestibular cue ( ves) only; observers are standing on a platform which is being rotated. (2) Treadmill stepping, podokinesthetic cue ( pod) only; observers step counter to the rotating platform so as to remain stable in space. (3) Active turning, ves and pod available; observers step around on the stationary platform. In all three tasks, angular velocity varied from trial to trial (15, 30, 60 degrees /s) but was constant during trials. Perception was probed by having the observers signal when they thought to have reached a previously instructed angular displacement, either in space or relative to the platform ("target"; range 60-1080 degrees ). Performance was quantified in terms of the targeting gain (displacement reached by the observer divided by target angle) and of the random error ( E(r)), which records an observer's deviation during single trials from his average performance. Confirming previous observations, E(r) was found to be significantly smaller during active turning than during passive turning, and we now complement these observations by showing that it is also significantly smaller than during treadmill stepping. This behaviour of E(r) is compatible with the idea that ves and pod be averaged during active turning. On the other hand, the observed characteristics of the targeting gain ( G(T)) support this idea only for the case of fast rotations (60 degrees /s); at lower velocities, the gain found during active turning was clearly not the average of the G(T) values recorded in the passive and the treadmill modes. We therefore also discuss alternative scenarios as to how ves and pod could interact, among these one based on the concept of a vestibular eigenmodel. A common denominator of these scenarios is that ves assumes the role of a prerequisite for an optimal use of pod during turning on a stationary support, without itself entering the calculation of displacement perception; this perception would be based exclusively on pod. Finally, it was a consistent observation that during passive rotations cognitive mechanisms fill in for the decaying vestibular signal in the context of the present navigation task, enabling observers to achieve large displacements surprisingly well although the duration of these movements exceeds by far the conventionally cited value of the central vestibular time constant (=20 s). 相似文献
9.
为了检测被动型neymanng肾炎(PHN)大鼠细胞免疫状况,我们将抗肾小管刷状缘的抗体腹腔注射大鼠体内而建立了被动Heymann肾炎模型,在PHN的最初28d,用MTT比色法检测了7d.14d、28d时外周血淋巴细胞诱生IL-2水平的变化,结果7d时IL-2水平为26.52±10.72U/ml,与正常对照组39.80±9.40U/ml相比显著差异(P<0.01),14d时IL-2水平为30.68±11.79U/ml(P<O.05),28d时IL-2水平为32.72±8.72U/ml(P<0.05),提示PHN大鼠存在免疫功能紊乱。 相似文献
10.