Estimation of free glutamic acid in the differentiating central nervous system of the chick

Zusammenfassung Es wird der Gehalt an Glutaminsäure in den embryonalen Entwicklungsstadien des Hühnergehirns festgestellt.     

Surface tension of cell types in differentiating CNS of chick

Zusammenfassung Es wird gezeigt, dass die Oberflächenspannung von Neuroblasten sich mit zunehmender Differenzierung ändert. Es kann ein kraniokaudaler Entwicklungsgradient nachgewiesen werden.     

Evidence for a direct action of monamines on the chick central nervous system

Zusammenfassung Pharmakologische Untersuchungen im Hinblick auf eine eventuelle Wechselwirkung von psychotropen Pharmaka und biogenen Aminen ergaben: (1) offenbares Eindringen von 5-HT, DA und NE in das Zentralnervensystem junger Hühner. (2) Schlafcharakteristisches Verhalten von EEG und Verhaltensweise nach Verabreichung von 5-HT und NE. (3) Auftreten der ?arousal?-Charakteristika mit anf?nglicher Akinese im EEG und Verhalten nach Dopamin- oder Dopazufuhr.

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Supported by U.S.P.H.S. Grant No. 5 TI MH-6415.     

Distribution of type A and B monoamine oxidase activities in the central nervous system of rat and chick

Summary The distribution of type A and B monoamine oxidase (MAO) activities in the central nervous system (CNS) of rat and chick was investigated using 5-hydroxytryptamine and -phenylethylamine as specific substrates. The distribution of type A MAO was similar to that of type B MAO in rat CNS, but quite different in chick CNS. This may be ascribed to the difference in animal species. The major part of MAO activity in the spinal cord was found to be type A.     

A central nervous system depressant-antidepressant.

A new tricyclic agent with an allenyl side chain experimentally shows antidepressant activity similar to amitriptyline and imipramine but also exerts marked CNS depression. Such dual activity should be of clinical interest for treatment of mixed anxiety and depression.     

Distribution of type A and B monamine oxidase activities in the central nervous system of rat and chick.

The distribution of type A and B monamine oxidase (MAO) activities in the central nervous system (CNS) of rat and chick was investigated using 5-hydroxytryptamine and beta-phenylethylamine as specific substrates. The distribution of type A MAO was similar to that of type B MAO in rat CNS, but quite different in chick CNS. This may be ascribed to the difference in animal species. The major part of MAO activity in the spinal cord was found to be type A.     

Multitasking with neurotensin in the central nervous system

The 13-amino acid peptide neurotensin (NT) was discovered over 30 years ago and has been implicated in a wide variety of neurotransmitter and endocrine functions. This review focuses on four areas where there has been substantial recent progress in understanding NT signaling and several functions of the endogenous peptide. The first area concerns the functional activation of the high-affinity NT receptor, NTR-1, including the delineation of the NT binding pocket and receptor domains involved in functional coupling to intracellular signaling pathways. The development of NT receptor antagonists and the application of genetic and molecular genetic approaches have accelerated progress in understanding NT function in several areas, including the involvement of NT in antipsychotic drug actions, psychostimulant sensitization and the modulation of pain, and these are reviewed in that order. There is now substantial evidence indicating that NT is required for certain antipsychotic drug actions and that the peptide plays a key role in stress-induced analgesia.Received 18 March 2005; received after revision 9 May 2005; accepted 23 May 2005     

Heat shock response in the central nervous system

The heat shock response is induced in nervous tissue in a variety of clinically significant experimental models including ischemic brain injury (stroke), trauma, thermal stress and status epilepticus. Excessive excitatory neurotransmission or the inability to metabolically support normal levels of excitatory neurotransmission may contribute to neuronal death in the nervous system in many of the same pathophysiologic circumstances. We demonstrated that in vitro glutamate-neurotransmitter induced excitotoxicity is attenuated by the prior induction of the heat shock response. A short thermal stress induced a pattern of protein synthesis characteristic of the highly conserved heat shock response and increased the expression of heat shock protein (HSP) mRNA. Protein synthesis was necessary for the neuroprotective effect. The study of the mechanisms of heat shock mediated protection may lead to important clues as to the basic mechanisms underlying the molecular actions of the HSP and the factors important for excitotoxic neuronal injury. The clinical relevance of these findings in vitro is suggested by experiments performed by others in vivo demonstrating that pretreatment of animals with a submaximal thermal or ischemis stress confers protection from a subsequent ischemic insult.     

Developmental and pathological angiogenesis in the central nervous system

Angiogenesis, the formation of new blood vessels from pre-existing vessels, in the central nervous system (CNS) is seen both as a normal physiological response as well as a pathological step in disease progression. Formation of the blood–brain barrier (BBB) is an essential step in physiological CNS angiogenesis. The BBB is regulated by a neurovascular unit (NVU) consisting of endothelial and perivascular cells as well as vascular astrocytes. The NVU plays a critical role in preventing entry of neurotoxic substances and regulation of blood flow in the CNS. In recent years, research on numerous acquired and hereditary disorders of the CNS has increasingly emphasized the role of angiogenesis in disease pathophysiology. Here, we discuss molecular mechanisms of CNS angiogenesis during embryogenesis as well as various pathological states including brain tumor formation, ischemic stroke, arteriovenous malformations, and neurodegenerative diseases.     

Neurotrophins and neuronal differentiation in the central nervous system

The central nervous system requires the proper formation of exquisitely precise circuits to function properly. These neuronal circuits are assembled during development by the formation of synaptic connections between hundreds of thousands of differentiating neurons. For these circuits to form correctly, neurons must elaborate precisely patterned axonal and dendritic arbors. Although the cellular and molecular mechanisms that guide neuronal differentiation and formation of connections remain mostly unknown, the neurotrophins have emerged recently as attractive candidates for regulating neuronal differentiation in the developing brain. The experiments reviewed here provide strong support for a bifunctional role for the neurotrophins in axonal and dendritic growth and are consistent with the exciting possibility that the neurotrophins might mediate activity-dependent synaptic plasticity.     

An antinicotinic action of papaverine in the central nervous system

Zusammenfassung Die Wirkungen von Papaverin auf die kortikale Aktivität des Präparates «encéphalé isolé» der Katzen wurden untersucht. Papaverin rief homogene kortikale Synchronisation für einige Minuten hervor und verminderte kortikale Nikotin-Desynchronisation für einige Stunden.     

Axon guidance at the central nervous system midline

A key feature of the central nervous system of most higher organisms is their bilateral symmetry about the midline. The specialised cells that lie at the midline have an essential role in regulating the axon guidance decisions of both neurons that project axons across the midline and those that project on one side. The midline cells produce both attractive and repellent short- and long-range signals to guide axonal growth. The axons themselves express specific receptors that can be dynamically regulated in response to midline-derived signals. In this way, axons extend toward or away from the midline and those that do cross change their behaviour to respond to longitudinal signals on the contralateral side.     

Effects of 18-hydroxydeoxycorticosterone on central nervous system excitability

The effects of 18-hydroxydeoxycorticosterone (18-OH-DOC) on central nervous system excitability were studied in adrenalectomized rats. Sixty-four evoked potentials (EP) recorded from the pontine reticular formation were averaged before and after the injection of vehicle and hormone. 750 micrograms of 18-OH-DOC dissolved in 0.5 ml of a 4:1 saline Cremophor-EL solution were injected i.v. A decrease of 55.7 +/- 6.1% in the amplitude of the EPs was observed with the hormone 16.3 min +/- 2.7 (SE) after injection. Amplitude values returned to baseline levels 38 min +/- 6.8 (SE) after injection. The secretion of 18-OH-DOC is greatly increased by ACTH and might modulate central nervous system function.     

Neuronal and glial markers of the central nervous system

Summary This brief review evaluates the expression of cell-specific markers on differentiated neural cells and, where necessary, on their developing precursors. Within these limitations only the commonly used markers are discussed and those deemed unequivocal are only briefly appraised.     

Neuronal and glial markers of the central nervous system

This brief review evaluates the expression of cell-specific markers on differentiated neural cells and, where necessary, on their developing precursors. Within these limitations only the commonly used markers are discussed and those deemed unequivocal are only briefly appraised.