Elevated beta-endorphin in cerebrospinal fluid after electrical brain stimulation: artifact of contrast infusion?

Beta-Endorphin-like immunoreactivity in cerebrospinal fluid was assayed in 11 patients receiving electrical stimulation of the brain for chronic pain. Immunoreactivity increased dramatically after contrast ventriculography prior to stimulation. No further elevations were observed after stimulation. The magnitude and time course of elevations were identical after placement of electrodes either in the thalamus or in the periventricular gray matter. These results suggest that previous findings of stimulation-induced elevation of beta-endorphin-like immunoreactivity in cerebrospinal fluid are attributable to an artifact of contrast ventriculography.     

Indole-3-acetic acid in human cerebrospinal fluid: identification and quantification by mass fragmentography

Indole-3-acetic acid has been identified in human cerebrospinal fluid by the gas chromatographic-mass spectrometric technique called mass fragmentography. A specific and sensitive method for quantitative determination of indole-3-acetic acid down to 2 nanograms per milliliter of cerebrospinal fluid has been developed. Samples of cerebrospinal fluid from 24 patients with depression contained 6.1 +/- 3.1 (range 2.6 to 15.8) nanograms of indole-3-acetic acid per milliliter.     

Suprachiasmatic nucleus vasopressin messenger RNA: circadian variation in normal and Brattleboro rats

In situ hybridization of an oligonucleotide probe complementary to vasopressin messenger RNA (mRNA) in sections from normal or Brattleboro rat hypothalami revealed hybridization densities in each of three vasopressin-rich nuclei: the supraoptic, paraventricular, and suprachiasmatic. When entrained to a daily light-dark cycle, each rat strain displayed diurnal variation in hybridizable mRNA in the suprachiasmatic, but not in the supraoptic or paraventricular nuclei. The higher values for suprachiasmatic mRNA in the morning correlate well with previously elucidated morning increases in vasopressin immunoreactivity in the cerebrospinal fluid. These results support the utility of in situ hybridization techniques for elucidating physiological influences on regional peptidergic function, are consistent with a prominent role for vasopressinergic suprachiasmatic neurons in generating the cerebrospinal fluid vasopressin rhythm, and suggest that regulation of this mRNA rhythm is not dependent on release of intact peptide.     

Choroid plexus and cerebrospinal fluid production

Acute progressive hydrocephalus occurred in 76 rhesus monkeys undergoing ventricular obstruction 2 to 6 months after choroid plexectomy and was only slightly less pronounced than in 73 nonplexectomized animals with similar ventricular obstructions. The composition of cerebrospinal fluid after choroid plexectomy was essentially normal. Experiments with ventricular perfusion techniques indicate only a slight reduction in cerebrospinal fluid production after choroid plexectomy. Thus, the choroid plexus is probably not the sole or even the major source of cerebrospinal fluid within the primate ventricular system.     

Multiple sclerosis: correlation between immunoglobulin-G in cerebrospinal fluid and brain

There is a positive correlation between the concentration of immunoglobulin-G in plaques of demyelination due to multiple sclerosis (as well as in white matter of normal appearance) and the concentration of this globulin in the cerebrospinal fluid. The tentative conclusion drawn from these results was that, in patients with multiple sclerosis, the increase in immuno-globulin-G in the cerebrospinal fluid is a reflection of an excess of this globulin in the brain.     

Central norepinephrine metabolism in affective illness: MHPG in the cerebrospinal fluid

Concentrations of the norepinephrine metabolite 3-methoxy-4-hydroxyphenyl glycol in cerebrospinal fluid were measured by a gas chromatographic method in 34 patients with affective illness and in 44 controls. Concentrations of this metabolite in spinal fluid were significantly lower in depressed patients than in controls or manic patients. These low values may occur secondary to depressive phenomena such as reduced psychomotor activity, or they may reflect a primary change in norepinephrine metabolism in depressive illness.     

Cerebrospinal fluid production by the choroid plexus and brain

The production of cerebrospinal fluid and the transport of (24)Na from the blood to the cerebrospinal fluid were studied simultaneously in normal and choroid plexectomized rhesus monkeys. Choroid plexectomy reduced the production of cerebrospinal fluid by an average of 33 to 40 percent and the rate of appearance of (24)Na in the cerebrospinal fluid and its final concentration were proportionately reduced. In both normal and plexectomized animals, (24)Na levels were found to be markedly greater in the gray matter surrounding the ventricles and in the gray matter bordering the subarachnoid space. That sodium exchanges in these two general areas of the brain may be linked to the formation of the cerebrospinal fluid is discussed here.     

Immunoreactive dynorphin-(1-8) and corticotropin- releasing factor in subpopulation of hypothalamic neurons

Immunoreactive corticotropin-releasing factor (CRF) and dynorphin-(I-8) were visualized in rat hypothalamus by immunohistofluorescence with specific antibodies. In brains from colchicine-treated, adrenalectomized rats, neuronal perikarya with immunoreactive CRF were observed in the paraventricular nucleus of the hypothalamus. The CRF occurred together with the dynorphin-(1-8). However, the CRF immunoreactivity occurred only in a subpopulation of the dynorphin-(1-8) immunoreactive cells. These findings suggest that there may be a functional interrelationship of CRF with dynorphin-related opioid peptides and provide further evidence that neurons may contain more than one bioactive substance.     

新型隐球菌性脑膜脑炎的临床症状及MRI特点

目的研究新型隐球菌脑膜脑炎的临床特点及MRI特点.方法收集北华大学附属医院1999-2005年间确诊为新型隐球菌性脑膜脑炎的12例患者,分析相关资料.结果12例患者中,脑脊液压力正常3例,升高9例,10例涂片阳性,2例脑脊液培养阳性.MRI示2例正常,10例异常,为长T1、长T2信号.治愈10例,死亡1例,自动出院1例.结论临床症状、体征及脑脊液改变,加之MRI特点是早期诊断和治疗新型隐球菌脑膜脑炎的重要信息,对疾病的转归及预后密切相关.     

Alpha-ketoglutaramate: increased concentrations in the cerebrospinal fluid of patients in hepatic coma

alpha-Ketoglutaramate, a deaminated metabolite of glutamine not previously identified in biological tissues, was measured in the cerebrospinal fluid of human subjects and found to be increased three- to tenfold in patients with hepatic coma. When perfused into the cerebral lateral ventricles of rats, alpha-ketoglutaramate (10 mM) depressed the animals' nocturnal locomotor activity, and at higher doses induced circling behavior and myoclonus. The concentration of alpha-ketoglutaramate in cerebrospinal fluid appears to be a reliable diagnostic indicator of hepatic coma, and its accumulation may contribute to the pathogenesis of this disease.     

二甲苯胺噻唑对绵羊血液及脑脊液中去甲肾上腺素的影响

试验用ＨＰＬＣ法研究了二甲苯胺噻唑（静松灵）对神经递质去甲肾上腺素（ＮＥ）的影响．绵羊肌注２．５ｎｇ／ｋｇ静松灵后，脑脊液及血液中ＮＥ含量呈持续性减少，３小时降到最低．血液中０时ＮＥ浓度３．６９９±０．３８１ｎｇ／ｍＬ，３小时ＮＥ含量０．５５９±０．１１７ｎｇ／ｍＬ（±ＳＥ，ｎ＝５，Ｐ＜０．０１），下降了８３．８％；脑脊液中ＮＥ浓度０时３１．３２±４．８８ｎｇ／ｍＬ，３时６．２６±２．００ｎｇ／ｍＬ（±ＳＥ，ｎ＝４，Ｐ＜０．０１），下降了８０％。血液与脑脊液中ＮＥ浓度变化呈正相关ｒ＝０．９３１．这两种体液中ＮＥ含量变化揭示了静松灵对中枢交感神经系统有抑制作用，静松灵的镇静、镇痛、中枢抑制作用与递质ＮＥ有密切关系．     

Interleukin-1 stimulates the secretion of hypothalamic corticotropin-releasing factor

There is now evidence that the immune system, during times of infectious challenge, can stimulate the secretion of glucocorticoids, the adrenal steroids that mediate important aspects of the response to stress. Specifically, secretion of interleukin-1 (IL-1), a monocyte lymphokine secreted after infection, appears at least in part responsible for this effect. Glucocorticoids are secreted in response to a neuroendocrine cascade involving, first, the brain, then the pituitary, and finally the adrenal gland. In this report, human IL-1 is shown to activate the adrenocortical axis at the level of the brain, stimulating the release of the controlling hormone corticotropin-releasing factor (CRF) from the hypothalamus. Infusion of IL-1 induced a significant secretion of CRF into the circulation exiting the hypothalamus, whereas immunoneutralization of CRF blocked the stimulatory effect of IL-1 on glucocorticoid secretion. IL-1 appeared to have no acute direct stimulatory effects on the pituitary or adrenal components of this system. Furthermore, IL-1 did not cause a nonspecific release of other hypothalamic hormones. Thus, the lymphokine acts in a specific manner to activate the adrenocortical axis at the level of the brain; this effect appears to be unrelated to the known pyrogenic effects of IL-1 within the hypothalamus.     

Enkephalin-like material elevated in ventricular cerebrospinal fluid of pain patients after analgetic focal stimulation

Enkephalin-like activity has been measured in the ventricular cerebrospinal fluid of patients with intractable pain. Electrical stimulation of periventricular brain sites resulted in significant decrease in persistent pain in these subjects. This analgesia, which was blocked by naloxone in 80% of the cases, was accompanied by a significant rise in ventricular enkephalin-like activity, as measured by two different methods. The results present evidence of in vivo release of enkephalin-like material in humans and suggest that stimulation analgesia may be partially due to this release.     

催乳素释放肽抗应激功能研究进展

催乳素释放肽(PrRP)是RF肽的一个新成员,通过与G蛋白偶联受体结合,起着很多重要的生理调控作用,但其确切生理作用还有待进一步的探讨和研究。催乳素释放肽可通过多种途径作用于下丘脑——垂体——肾上腺轴,参与应激的调节。综述了目前有关催乳素释放肽在调节应激方面的研究进展。     

Biogenic amine metabolites in cerebrospinal fluid of depressed and manic patients

A reduction in 5-hydroxyindoleacetic acid in cerebrospinal fluid was found in depressed and manic patients both while they were symptomatic and also after treatment. The concentration of homovanillic acid was initially reduced and then tended to increase after treatment.     

Endogenous anticonvulsant substance in rat cerebrospinal fluid after a generalized seizure

Cerebrospinal fluid taken from rats subjected to electroshock-induced seizures and injected into the cerebral ventricles of rats that had not been shocked increased the seizure threshold of the recipients. The anticonvulsant activity of the donor cerebrospinal fluid was antagonized by opioid antagonists and enhanced by peptidase inhibitors. These results suggest the existence of an endogenous anticonvulsant substance in rat cerebrospinal fluid, possibly opioid in nature, which is activated as a consequence of a seizure and which may play a critical role in postseizure inhibition.     

Reduced numbers of somatostatin receptors in the cerebral cortex in Alzheimer's disease

Somatostatin receptor concentrations were measured in patients with Alzheimer's disease and controls. In the frontal cortex (Brodmann areas 6, 9, and 10) and temporal cortex (Brodmann area 21), the concentrations of somatostatin in receptors in the patients were reduced to approximately 50 percent of control values. A 40 percent reduction was seen in the hippocampus, while no significant changes were found in the cingulate cortex, postcentral gyrus, temporal pole, and superior temporal gyrus. Scatchard analysis showed a reduction in receptor number rather than a change in affinity. Somatostatin-like immunoreactivity was significantly reduced in both the frontal and temporal cortex. Somatostatin-like immunoreactivity was linearly related to somatostatin-receptor binding in the cortices of Alzheimer's patients. These findings may reflect degeneration of postsynaptic neurons or cortical afferents in the patients' cerebral cortices. Alternatively, decreased somatostatin-like immunoreactivity in Alzheimer's disease might indicate increased release of somatostatin and down regulation of postsynaptic receptors.     

Transport of 1-aminocyclopentanecarboxylic acid from feline cerebrospinal fluid

1-Aminocyclopentanecarboxylic acid was cleared from cerebrospinal fluid of the cat by a saturable mechanism. Clearance was inhibited by naturally occurring neutral amino acids. Carrier transport may explain the low ratio of amino acid in spinal fluid to that in plasma.     

乏情期奶山羊下丘脑催产素样神经元的分布

为了揭示不同生理期催产素(Oxytocin,OT)在下丘脑-垂体-性腺轴中的分布特点,采用链霉素抗生物素蛋白-过氧化物酶(Streptaridin-peroxidase,SP)法研究了OT免疫反应产物在乏情期奶山羊下丘脑中的分布。结果显示:OT样神经元存在于视上核、室旁核弓状核、室周核、穹隆周核、下丘脑前核、下丘脑后核、腹外侧核、背内侧核、下丘脑外侧区以及乳头体各核团等27个核区,分布区域呈前端尖、中部宽、后钝圆的梭形带。此外,在室旁核观察到大量的强阳性神经纤维,第三脑室附近的纤维伸向脑室内。说明OT在下丘脑广泛存在,且下丘脑OT经神经垂体、第三脑室、血管3条途径释放,经血液循环最终作用于靶细胞而发挥生理作用。     

Cabbage aphid: effect of isolation on form and on endocrine activity

Isolated wingless cabbage aphids, Brevicoryne brassicae (L.), produced only wingless young. Aphids isolated from birth all became wingless, whereas over 50 percent of grouped controls developed wings. Isolation caused hyperactivity of the corpus allatum; this hyperactivity may have caused the wingless form.