Clinical Neuroscience

[The antinociceptive effect of kynurenic acid]

KÉKESI Gabriella, HORVÁTH Gyöngyi

OCTOBER 20, 2002

Clinical Neuroscience - 2002;55(09-10)

[It is well known that glutamate receptors have significant role in the pain transmission. The activation of N-methyl-Daspartate receptors causes persistent pain, therefore the antagonists acting on these receptors cause antinociception in chronic pain states. As the synthetic N-methyl-D-aspartate receptor antagonists have several side effects, they are not used generally in the clinical therapy. The tryptophan metabolite kynurenic acid is an endogenous antagonist of N-methyl-D-aspartate receptors. Although some data proved its neuroprotective effect, only a few studies suggest the antinociceptive potential of kynurenic acid. The goal of this review to summarise the possible role of kynurenic acid in the pain therapy based on the results of animal studies. Data available concerning this subject demonstrated that kynurenic acid is not an appropriate agent for antinociception neither in single nor in continuous administration because of its side-effect resulting in motor deficiency. On the other hand the combination of low doses of kynurenic acid and endomorphin-1 provides effective antinociception without side-effects on inflammatory pain test, thus may offer a new treatment modality in human pain therapy.]



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Clinical Neuroscience

[Dezsõ Miskolczy, the founder of modern neurology in Hungary]


[Dezsõ Miskolczy, the founder of modern neurology in Hungary 2002;55(09-10)]

Clinical Neuroscience

[The role of transcranial magnetic stimulation in clinical diagnosis: motor evoked potential (MEP)]

ARÁNYI Zsuzsanna, SIMÓ Magdolna

[Transcranial magnetic stimulation allows painless, non-invasive stimulation, neurophysiological evaluation of nervous structure covered by bone or difficult to access for other reasons. In the clinical setting the technique is mainly used for the investigation of the corticospinal tract (motor evoked potential: MEP). Based upon our experience with patients examined over the course of four years, we have attempted to highlight the clinical situations, where diagnostic help is provided by this technique. MEP in general has proved to be a sensitive and reliable examination. Its significance is apparent mainly in situations where clinical signs of corticospinal tract dysfunction are not evident, or they are masked by lower motoneurone involvement, and where neuroimaging techniques are not informative. The demonstration of subclinical corticospinal lesion is often essential to establish the diagnosis in multiple sclerosis and amyotrophic lateral sclerosis. The technique however received little attention so far with respect to its role in the diagnosis of various spinal cord disorders, and in the demonstration of intact corticospinal function in case of weakness, psychogenic in origin. We have endeavoured to provide further evidence in support of this, and thereby advocating a wider clinical application of the technique.]

Clinical Neuroscience

[Anxiety in epilepsy - based on two case reports]

BARAN Brigitta, FARKAS Márta, RAJNA Péter

[There are a great number of psychopathological symptoms which manifest themselves in 70-75% of epileptic patients but most of them remain unrecognised and untreated. These symptoms may affect the patients’ quality of life more negatively than the epileptic seizures themselves. Anxiety is one of the most frequently occurring interictal psychopathological symptom. A number of specialists agree that chronic epilepsy causes the amplification of endogenic seizure suppressing mechanisms which hinder the epileptic seizures and are responsible for the development of interictal psychopathological symptoms. However the physiological effects of the interictal psychopathological conditions (e.g. anxiety) have epileptogenic effect as well. There is a high chance that the conditions of epilepsy and anxiety will mutually create a destructive vicious circle and it will be illustrated by our two case reports. In our experience, before modifying the pharmacotherapy of a patient suffering from chronic epilepsy with increased frequency of seizures, the anxiety level should be defined; and if it is high it should be treated first. From our perspective, the so-called ”rational bitherapy” is very effective when a high potential antiepileptic drug is combined with an anxiety reducing method. The latter can be drug related or consists only of psychotherapy. We need more controlled clinical research to prove that inside epilepsy there are risk groups as well as conditions of high risk when the connection between anxiety and epilepsy is more than evident. The described cases seem to indicate that the existence of periictal anxiety can be a risk factor in developing later interictal anxiety.]

Clinical Neuroscience

[Az epileptogén laesiók szerepe az interictalis és az ictalis epilepsziás működészavarban]


Clinical Neuroscience

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