[Receptors and mechanisms of neurotropic effects of cytokines and growth factors].

Cytokines and trophic factors (TF) are known to be involved not only into the immune processes but in majority cells, organs and physiological systems functional activity regulation as well as in pathological conditions. Cytokines and TF are shown to exert antagonistic effects on the brain, involved into local and systemic reactions modulation in response to CNS inflammation, infections and other types of injuries. Authors observed new data about cytokines and TF (particularly, the very biologically active among them - tumor necrosis factor-alpha and interleukin-1-beta) physico-chemical properties as the background for their neurotropic affects investigation. The contemporary data about cytokines and TF receptors, their interaction with neurotransmitters, penetration into the brain and their bioactivity regulation are reviewed.

[Neurotropic effects cytokines and trophic factors].

Cytokines and trophic factors (TF) are involved into the nervous system activity regulation that confirms by their secretion and receptors identification within nervous system. Cytokines and TF production increases tremendously in response to CNS alterations or other CNS pathologic events where they are modulated both alterative and protective effects. Authors observed the data of clinical and laboratory investigations concerning the cytokines and TF-neurotropic effects and also the original results dedicated to investigation of tumor necrosis factor-alpha and interleukin-1-beta influence on experimental seizure syndrome. The new data about cytokines and TF-neurotropic effects as well as their influence on the experimental seizure syndrome are reviewed. The clinical use of cytokines and TF-perspective is evaluated also.

The role of TNF-alpha in amygdala kindled rats.

In the present study, the interaction between epileptogenesis and the immune system were studied in a kindling model. First, the effects of a single administration of TNF-alpha (5.0 microg/kg, i.p.) on seizure and EEG activity were investigated in amygdala-kindled rats. TNF-alpha treated rats showed more prolonged epileptiformic discharges than control rats. TNF-alpha also induced a decrease in the power of delta band and an increase in theta and alpha activity. In addition, a marked increase in the power of beta and gamma band was observed. The EEG changes were most numerous in the frontal cortex and amygdala. All effects were registered 24 h after TNF-alpha administration. Finally, electrical stimulation enhanced the level of TNF-alpha in blood serum from 1.9 +/- 1.5 to 12.7 +/- 3.8 pg/ml and in brain tissue 56.8 +/- 6.0 to 109.2 +/- 6.0 pg/mg, as was determined via the ELISA method. It can be concluded that there is a mutual facilitative interaction of both epileptogenic and cytokine-derived mechanisms on this type of seizure. The changes in the power spectrum of the EEG after TNF-alpha might contribute to intensify thalamic-derived facilitation of epileptic discharge in cortical structures.

[A rotational syndrome induced by administration of the delta sleep-inducing peptide into the reticular portion of the rat substantia nigra]. / Rotatsionnyi sindrom, vyzyvaemyi vvedeniem del'ta-son-indutsiruiushchego peptida v retikuliarnuiu chast' chernogo veshchestva krys.

Unilateral intranigral administration of a delta-sleep-induced peptide (DSIP) evoked a contralateral rotation. Naloxon prevented development of the effect whereas haloperidol administration enhanced the DSIP cataleptogenic effect.

The influence of activation of the superior colliculi on convulsive activity during picrotoxin kindling.

It has been demonstrated in experiments in rats in which kindling was induced by repeated subconvulsive doses of picrotoxin (1.0 mg/kg) that the bilateral microinjection of picrotoxin, bicuculline, and penicillin into the deep layers of the superior colliculi of the corpora quadrigemina leads to the appearance of a generator of pathologically intensified excitation. An increase in the latent period of the initial convulsive manifestations, the suppression of clonic-tonic convulsive attacks, as well as the prevention of generalized epileptic activity induced by the systemic utilization of picrotoxin were observed under the conditions of the appearance of a generator of pathologically intensified excitation. An inference was drawn regarding the role of the superior colliculi in the mechanisms of the suppression of convulsive activity and regarding their inclusion in the antiepileptic system.

[The effect of activation of the superior colliculus on the convulsive activity during picrotoxin-induced kindling]. / Vliianie aktivatsii verkhnikh bugorkov chetverokholmiia na sudorozhnuiu aktivnost' pri pikrotoksinovom kindlinge.

Bilateral administration of picrotoxin, bicucullin or benzilpenicillin to the colliculi superior induced high-amplitude hypersynchronous discharges in rats. In these conditions, a suppression of generalized seizures induced with picrotoxin, was observed. The superior colliculi seem to play a significant part in antiepileptic system, the part being realized through generator mechanism.