脑室注射γ—氨基丁酸对大鼠尾核痛反应神经元放电的影响

本文在32只大鼠上,用玻璃微电极引导神经元放电,观察了脑室注射γ-氨基丁酸(GABA)后,尾核痛反应神经元电活动的规律和印防已毒素(picrotoxin,PIX)对GABA的阻断效应。研究所见:当脑内GABA含量增加时,尾核痛兴奋神经元(pain excitation neurons,PEN)电活动受到抑制,表现为痛诱发放电频率下降,潜伏期延长;痛抑制神经元(pain inhibition neurons,PIN)电活动加强,表现为抑制时程缩短,痛诱发放电频率增加。PIX可阻断这种效应。综上表明,GABA通过同时影响尾核PEN和PIN的电活动而产生镇痛效应。     

催产素对大鼠尾核痛反应神经元放电的影响

实验用Ｗｉｓｔｅｒ大鼠４８只，在尿酯（１．０ｇ／ｋｇ）麻醉下行常规手术，人工呼吸条件下进行实验。用玻璃微电极引导尾核中痛反应神经元（ＰＥＮ、ＰＩＮ）的放电，研究外源、内源催产素（ＯＴ）对其放电的影响。结果：１．尾核内微量注射ＯＴ（０．００５Ｕ／２μ可明显抑制ＰＥＮ放电频率，延长放电潜伏期．可缩短ＰＩＮ放电抑制时时程、增加放电频率。以上放电变化高峰出现在注药后６ｍｉｎ，注药后１５ｍｉｎ恢复，２．电刺     

电刺激大鼠尾核头部对丘脑后核中内脏痛反应神经元电活动的影响

电刺激同侧尾核头部(HCN)能抑制多数内脏痛兴奋神经元和内脏痛抑制神经元的电活动,使其自发放电减少或消失、内脏痛刺激引起的增频或减频效应减弱或消失。电刺激对侧的HCN也能抑制PO核中多数内脏痛反应神经元的活动,其抑制作用与同侧比较无明显差异。     

海人酸对家兔海马和尾核神经元的作用

本文比较了成年兔和幼年兔神经元对海人酸的敏感性,并观察了海人酸对家兔海马和尾核神经元的作用。主要结果为: 1.成年兔侧脑室内注射不同剂量的海人酸后,海马不同部位的神经元有不同程度的损伤。注射剂量为0.8μg时,CA_3和CA_4区的大部分锥体细胞有明显的溃变,细胞皱缩,着色深,并有胶质细胞增生;同时尾核神经元也有严重损伤,胶质细胞大量增生。剂量为0.5μg或0.3μg时,CA_3和CA_4的锥体细胞约有1/2被破坏。剂量增至1μg时,锥体细胞损伤范围扩大,溃变更严重。 2.幼兔侧脑室内注射0.1μg或0.2μg海人酸后,海马的锥体细胞有一定的损伤,但仪限于CA_3a区。 3.向成年兔海马CA_2区注射0.3μg海人酸后,海马神经元即有明显的损伤,但只局限于注射的部位。成年兔尾核头部注射0.3μ海人酸后,可在注射部位观察到损伤的神经元和数在的胶质细胞。成年家兔海马锥体细胞对海人酸的敏感性较幼兔为强。海人酸对家兔海马锥体细胞的作用比较强,同时尾核神经元对海人酸也有一定的敏感性。     

大鼠三叉神经尾侧亚核内甘氨酸受体和甘氨酸阳性神经元的分布

目的 研究大鼠三叉神经尾侧亚核内甘氨酸受体和甘氨酸阳性神经元的分布及其匹配关系,方法：免疫细胞化学染色技术,结果：甘氨酸受体免疫组化染色阳性胞体和纤维分布于三叉神经尾侧亚核各层,尤以浅层密集,甘氨酸阳性胞体在每层均有广泛分布,甘氨酸阳性纤维及终末密集分布于三叉神经脊束核尾侧亚核的浅层,深层的阳性纤维及终末呈散在线性分析,结论 上述结果表明在三叉神经尾侧亚核浅层甘氨酸阳性纤维和终末的分布与甘氨酸受体     

脑震荡对大鼠脑内乙酰胆碱M1受体亚型的影响

脑震荡是轻型闭合性脑损伤,占颅脑外伤患者的75．5%～78．2%。脑震荡后主要表现为立即出现短暂性昏迷与记忆障碍,其中学习记忆能力的损害是最持久和对患者影响最重的症状之一[2～4],国内外对开放性脑损伤的认知行     

尾加压素Ⅱ对大鼠下丘脑室旁核神经元放电的影响

应用细胞外记录单位放电技术,在大鼠下丘脑脑片上观察了尾加压素Ⅱ(urotensinⅡ)对下丘脑室旁核(paraventricular nucleus,PVN)神经元放电的影响。实验结果如下:(1)在39个PVN神经元放电单位给予尾加压素Ⅱ(0.3,3.0,30.0,300.0nmol/L,n=39)2min,有32个放电单位(82.05%)放电频率明显降低,且呈剂量依赖性;(2)预先用100μmol/L的GABAA受体拮抗剂荷包牡丹碱灌流7个下丘脑脑片,5个放电单位放电频率明显增加(71.43%),在此基础上灌流尾加压素Ⅱ(30.0nmol/L)2min,放电频率无明显变化;(3)预先用氯通道阻断剂印防己毒素(picrotoxin)灌流12个下丘脑脑片,12个放电单位的放电频率均明显增加(100%),在此基础上灌流尾加压素Ⅱ(30.0nmol/L)2min,11/12(91.67%)放电频率无变化;(4)12个放电单位灌流一氧化氮合酶抑制剂(NG-nitro-L-arginine methylester,L-NAME)50μmol/L,有11个单位(11/12,91.67%)放电明显增加,在此基础上灌流尾加压素Ⅱ(30.0nmol/L)2min,放电被抑制。以上结果提示:尾加压素Ⅱ能抑制下丘脑室旁核神经元自发放电,可能与其同GABAA受体结合加强氯电流有关。     

脑缺血早期大脑皮质和尾壳核一氧化氮合酶神经元的进程变化

目的：探讨一氧化氮合酶神经元在脑缺血早期（２４ｈ内）的变化规律。方法：ＮＡＤＰＨ－ｄ组织化学方法。结果：各组间正常侧ＮＯＳ神经元无明显变化，散在分布于皮质的Ⅱ～Ⅵ层，以Ⅳ～Ⅵ为主，尾壳核内ＮＯＳ神经元数量较多，密集分布于外侧区。缺血１５ｍｉｎ和３０ｍｉｎ组，缺血中心区皮质和尾壳核ＮＯＳ神经元数量减少，形态无明显变化；缺血１ｈ和２ｈ组，皮质和尾壳核内ＮＯＳ神经元数量进一步减少，突起变短；缺血３ｈ和６     

心肌缺血大鼠丘脑束旁核神经元放电频率的变化

当前大部分关于疼痛机制的信息是从躯体痛的研究得来的,有关心绞痛的临床和实验室资料非常有限。Rosen等（1994）的研究提示丘脑可能在心肌缺血性疼痛过程中起非常重要的作用。然而,大鼠丘脑束旁核（nucleus parafaseieularis of thalamus,Pf）在缺血性心绞痛过程中究竟发挥怎样的作用,文献一直没有报道。     

酚妥拉明阻断去甲肾上腺素对大鼠束旁核痛反应神经元电活动的影响

目的：去甲肾上腺素及其α受体阻断剂酚妥拉明对大鼠束旁核痛反应神经元电活动的影响。方法：以串刺激右侧坐骨神经为伤害性刺激，用玻璃微电极细胞外记录大鼠束旁核痛反应神经元电活动。结果：脑室去甲肾上腺素抑制旁核束旁核痛兴奋神经元放电，促进痛抑制神经元放电，此作用可被酚妥拉明阻断。结论：酚妥拉明阻断去甲肾上腺素对大鼠束旁核痛反应神经元电活动的抑制作用，提示去甲肾上腺素的镇痛作用与α肾上腺素能受体关系密切。     

Qualitative and quantitative analysis of changes in caudate nucleus neurons during postnatal development of rats

A qualitative and quantitative analysis was made of changes in caudate nucleus neurons of newborn rats and rats aged 7, 14, and 30 days. An increase in complexity of structure of components of the nerve cell was found during early postnatal ontogeny. Maturation of neurons takes place most intensively during the first 2 weeks of life and is virtually complete by the 30th day of the postnatal period. The results suggest that the caudate nucleus becomes involved in the integrative activity of the brain in this period of development.Laboratory of Functional Morphology and Pathohistology of the Brain and Laboratory of Architectonics of the Brain, Brain Institute, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Kupriyanov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 7, pp. 94–96, July, 1978.     

Role of neurochemical mechanisms of the caudate nucleus in different models of anxiety in rats

Microinjections of dopamine, apomorphine, and GABA to the dorsal part of the caudate nucleus decreased the level of anxiety in an illuminated platform avoidance task in rats, while sulpiride and picrotoxin increased it. Intrastriatal injection of serotonin, glutamic acid, yohimbine, and phenylephrine reduced anxiety in threatening situation, but not in the illuminated platform avoidance task. It is suggested that emotional states associated with different kinds of stress are realized through diverse neurochemical systems of the caudate nucleus neuronal network. Translated fromByulleten' Eksperimental'noi Biologii i Meditsyny, Vol. 128, No. 7, pp. 17–20, July, 1999     

Ipsiversive rotation in awake rats following chronic electrical stimulation of one caudate nucleus

Rats were chronically implanted with stimulating electrodes in one caudate nucleus. Under light anaesthesia they received daily electrical stimulation (100-400 microA/HZ) for 30 min on 4 consecutive days. During this period, and for up to 3 subsequent days, tests for possible circling behaviour in response to administration of apomorphine i.p. were performed daily. Turning occurred towards the treated side and was reversible. The possibility is discussed that high levels of dopamine are released into the striatum during electrical stimulation, inducing transient subsensitivity of striatal dopamine receptors.     

Effects of electric stimulation and destruction of caudate nucleus on short-term memory

The effects of stimulation and destruction of the caudate nucleus on the cat short-term memory were studied by the method of classical delayed reactions. Short-term memory improved, if electrical stimulation of the caudate nucleus before presentation of the conditioned signal caused desynchronization of the electrocorticogram in the prefrontal and temporal cortex. Unilateral destruction of the caudate nucleus leading to the development of hyperactivity and attention disorders deteriorated short-term memory.     

There are receptors for neurotensin in the caudate nucleus and posterior hypothalamus

It was established in chronic experiments on dogs that the introduction of neurotensin in a dose of 3 or 10 g in 1.5 l into the caudate nucleus changes the parameters of the conditioned and unconditioned food reflexes: a 31% shortening of the latent period and a 56% increase in the magnitude of the reflex. Microapplication of neurotensin in the same doses in the posterior region of the hypothalamus enhanced the secretory function of the gland caused by the introduction of histamine. It was concluded that the caudate nucleus and hypothalamus contain cells possessing receptors for neurotensin, which participate in mechanisms of formation of the conditioned reflex and central influence on the organs of the digestive system.Translated from Fiziologicheskii Zhurnal SSSR imeni I. M. Sechenova, Vol. 68, No. 5, pp. 627–631, May, 1982.     

Effect of parachlorophenylalanine and 5-hydroxytryptophan on the caudate nucleus in cats

Parachlorophenylalanine, an inhibitor of serotonin synthesis, raised the thresholds of the contraversive reaction, the arrest reaction, and the spindle waves accompanying it in the sensomotor cortex of unanesthetized, unrestrained cats during stimulation of the rostro-ventral zones of the caudate nucleus. The effects arising from the dorsomedial zones of the head and body of the nucleus changed in opposite directions. The serotonin precursor 5-hydroxytryptophan, on the other hand, potentiated most indices of caudate nuclear activity irrespective of the site of stimulation. The existence of serotoninergic mechanisms in the rostro-ventral zones of the nucleus antagonistic to the dopaminergic system and capable of triggering certain caudate functions is postulated.Department of Pharmacology, Chita Medical Institute, Ministry of Health of the RSFSR. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 3, pp. 296–299, March, 1978.     

Comparison of contralateral and ipsilateral rotatory responses to electrical stimulation of the caudate nucleus in cats

High-frequency stimulation of the caudate nucleus evoked two types of rotatory movements of the head and trunk in freely moving cats: in the contralateral and ipsilateral directions. Contralateral rotations (CR) were evoked from a wider area, mainly from the dorso-medio-central zones of the head of the nucleus. Conversely, ipsilateral rotations were evoked from the ventrolateral zone, they more often contained a tonic component, their amplitude was greater, and their sensitivity to L-dopa and chlorpromazine was less. Unilateral injury to the region evoking CR led to ipsilateral asymmetry of posture. When this asymmetry disappeared, injection of L-dopa or apomorphine easily evoked circular movements in the same direction. Removal of zones acting as the source of ipsilateral responses gave the opposite result.Department of Pharmacology, Medical Institute, Chita. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 142–145, February, 1978.     

Effect of amphetamine and caffeine on behavioral changes following electrical stimulation of the caudate nucleus in cats

Low doses of amphetamine (0.1–0.5 mg/kg), not affecting the spontaneous behavior of cats, prevent the appearance of behavioral depression after repetitive low-frequency stimulation of the caudate nucleus. Activation phenomena observed after the end of, stimulation are considerably potentiated, sometimes with stereotype formation. Caffeine (10–80 mg/kg), which may even activate spontaneous behavior in cats, does not prevent the development of caudate inhibition.Department of Pharmacology, Chita Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 12, pp. 685–688, December, 1979.     

Changes in amphetamine stereotypy in cats after electrical stimulation of the caudate nucleus

Two types of behavioral changes arise in cats after repetitive low-frequency stimulation of the head of the caudate nucleus in cats. Behavioral inhibition is more frequently triggered from the dorsomedial zone of the head, whereas activation phenomena precede depression during stimulation of the ventrolateral zone. The assortment and pattern of stereotyped movements following injection of the minimal effective dose of amphetamine vary in different ways against the background of these changes. After stimulation of the dorsomedial zones of the nucleus stereotypy is first disorganized and then weakened, whereas caudate activation is associated with strengthening of stereotypy.Department of Pharmacology, Chita Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 6, pp. 518–521, June, 1979.