[Naloxone-induced suppression of the behavioral manifestation of serotoninergic system hyperactivation by beta-casomorphins-7 in mice].

The effect of human and bovine beta-casomorphins-7 on the behavior of mice under conditions of 5-hydroxytryptophan (5-HT) induced hyperactivation of the serotoninergic system (head twitch test) has been studied. Intraperitoneal administration of each peptide in a dose of 1 mg/kg was shown to suppress the head twitch response in mice approximately by half (p < 0.01). This effect was completely blocked by the opioid receptor antagonist naloxone (10 mg/kg), which did not alter the behavior of mice in the head twitch test by itself. Thus, the influence of casomorphins on the serotoninergic system in vivo has been demonstrated for the first time. The role of 5-HT and opioid receptors in the mechanism of casomorphin action is discussed.

[A comparative analysis of distribution of glyprolines administered by various routes].

The distribution of the glyprolines Pro-Gly-Pro and Thr-Lys-Pro-Arg-Pro-Gly-Pro (Selanc) was analyzed and compared in tissues of rat organs after different ways of their administration using the peptides uniformly labeled with tritium. Comparative data on changes in concentrations of the peptides in the rat organs after their intraperitoneal, intranasal, intragastric, and intravenous administration are given. The intranasal administration of both peptides was shown to be optimal for the delivery of glyproline molecules in the CNS. A high affinity of the studied glyprolines for gastric tissues was found for all the ways of their administration. We suggest that a high efficiency of action of glyprolines on homeostasis of the gastric mucous tunic was partially provided by accumulation of these peptides (to high concentrations) in gastric tissues.

[Regulatory peptides and psychomotor development in infants].

Regulatory peptides (RP) are an important homeostatic factor. The maternal organism and placenta are substantial sources of RP for fetus during the prenatal period. Not only endogenous, but also exogenous RP play an important role during early postnatal period. In this study, the concentration of exogenous RP (casomorphins-7) and the activity of peptidases (enkephalinases) in the serum of breastfed and bottle-fed infants were estimated. Possible interrelation between these two parameters and the psychomotor development (PMD) of infants were evaluated. Using specially developed RIA, the investigators estimated the presence of human and bovine casomorphins immunoreactivity (CMir) in the serum of breastfed and bottle-fed infants. A distinct correlation of CMir with PMD was demonstrated. The activity of RP-degrading serum enzymes also correlated with PMD level. The role of endo- and exogenous peptides in normal PMD process and in the pathogenesis of early child autism is discussed in the article.

[Radioreceptor study of [3H]-olanzapine specific binding in the rat frontal cortex and striatum].

The direct radioreceptor assay was used to elucidate the interactions of clinically employed atypical antipsychotic drug olanzapine with the specific binding sites in rat brain membranes. Tritium-labeled olanzapine was obtained by isotope exchange method. HPLC and mass spectrometry assays confirmed the identity of [3H]-olanzapine to the initial compound. The specific [3H]-olanzapine binding sites of the two types were identified in frontal cortex by means of the method of Scatchard's plots. High affinity sites showed steady-state dissociation binding constant (KD) of 1.7 nM, which is indicative of olanzapine affinity to 5-HT-2a and histamine receptors. However, according to available literature data, the density of these receptors is several times smaller than that determined in our study (maximum number of binding sites corresponded to B(max) = 1.4 pmol/mg protein), thus allowing an assumption about the existence of yet unknown binding sites of the antipsychotic drug under consideration. Moderate affinity binding sites of olanzapine in frontal cortex (KD= 68.5 nM, B(max) = 10.8 pmol/mg protein) apparently correspond to dopamine, muscarinic, and alpha-1-adrenoceptors. [3H]olanzapine binding sites of the two types were also determined in striatum. The moderate-affinity sites of the receptor interaction had KD = 18.0 nM and B(max) = 13.0 pmol/mg protein. These values in fact correspond to D2 receptors, whose density prevails in this cortical region. The low-affinity binding sites of olanzapine in striatum had KD = 117.0 nM and B(max) = 32.5 pmol/mg protein.

[Evenly tritium-labeled peptides and their in vivo and in vitro biodegradation].

Biologically active peptides evenly labeled with tritium were used for studying the in vitro and in vivo biodegradation of the peptides. Tritium-labeled peptides with a specific radioactivity of 50-150 Ci/mmol were obtained by high temperature solid phase catalytic isotope exchange (HSCIE) with spillover tritium. The distribution of the isotope label among all amino acid residues of these peptides allows the simultaneous determination of practically all possible products of their enzymatic hydrolysis. The developed analytical method includes extraction of tritium-labeled peptides from organism tissues and chromatographic isolation of individual labeled peptides from the mixture of degradation products. The concentrations of a peptide under study and the products of its biodegradation were calculated from the results of liquid scintillation counting. This approach was used for studying the pathways of biodegradation of the heptapeptide TKPRPGP (Selank) and the tripeptide PGP in blood plasma. The pharmacokinetics of Selank, an anxiolytic peptide, was also studied in brain tissues using the intranasal in vivo administration of this peptide. The concentrations of labeled peptides were determined, and the pentapeptide TKPRP, tripeptide TKP, and dipeptides RP and GP were shown to be the major products of Selank biodegradation. The study of the biodegradation of the heptapeptide MEHFPGP (Semax) in the presence of nerve cells showed that the major products of its biodegradation are the pentapeptide HFPGP and tripeptide PGP. The enkephalinase activity of blood plasma was studied with the use of evenly tritium-labeled [Leu]enkephalin. A high inhibitory effect of Semax on blood plasma enkephalinases was shown to arise from its action on aminopeptidases. The method, based on the use of evenly tritium-labeled peptides, allows the determination of peptide concentrations and the activity of enzymes involved in their degradation on a tg scale of biological samples both in vitro and in vivo.

[A synthesis of tritium-labeled olanzapine].

A synthesis of olanzapine, 2-methyl-10-(4-methyl-1-piperazinyl)-4H-thieno[2,3-b][1,5]benzodiazepine was carried out, and the conditions for its tritium labeling were optimized, to get a tritium-labeled olanzapine preparation with molar radioactivity of 12 Ci/mmol.

[Leu-enkephalin homogeneously labeled with tritium in studying the Selank inhibiting effect on the enkephalin-degrading enzymes of human plasma]. / Odnorodno mechennyi tritiem [Leu]énkefalin v issledovanii ingibiruiushchego deistviia Selanka na énkefalindegradiruiushchie fermenty plazmy krovi.

A method of analysis of enkephalinase activity in blood plasma based on the application of Leu-enkephalin generally labeled with tritium at all its amino acid residues was developed. The method allows the simultaneous estimation of activity of several peptidases in microquantities of tissues. [G-3H]Leu-enkephalin was prepared by the method of solid phase catalytic isotope exchange (120 Ci/mmol) and subjected to proteolysis by the treatment with blood plasma. The resulting radioactive metabolites were separated by HPLC in the presence of the mixture of unlabeled fragments of Leu-enkephalin as internal standards. It was shown that aminopeptidases, dipeptidylaminopeptidases, and dipeptidylcarboxypeptidases respond for approximately 80%, 2%, and 10% of the total enzymatic activity, respectively. The new pathway of degradation of Leu-enkephalin by carboxypeptidase that provides for approximately 6% of the total enkephalin-degrading activity was discovered. Bestatin was shown to predominantly inhibit aminopeptidases and carboxypeptidases, whereas Selank is more specific for carboxypeptidases and dicarboxypeptidases. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 3; see also http://www.maik.ru.

[Semax and selank inhibit the enkephalin-degrading enzymes from human serum]]. / Ingibiruiushchee deistvie semaksa i selanka na énkefalindegradiruiushchie fermenty syvorotki krovi cheloveka.

A dose-dependent effect of synthetic heptapeptides Semax (Met-Glu-His-Phe-Pro-Gly-Pro) and Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro) on the enkephalin-degrading enzymes of human serum was demonstrated. The inhibitory effects of Semax (IC50 10 microM) and Selank (IC50 20 microM) are more pronounced than those of puromycin (IC50 10 mM), bacitracin, and some other inhibitors of peptidases. Beside the heptapeptides, their pentapeptide fragments also possessed an inhibitory effect; tri-, tetra-, and hexapeptide fragments did not display such an effect. As the above enzymes take part in degradation of not only enkephalins but also other regulatory peptides, it can be assumed that one of the mechanisms of biological activity of Semax and Selank is related to this inhibitory activity of theirs.

[Reaction between endogenous opiates and human peripheral blood lymphocytes]. / Izuchenie vzaimodeistviia éndogennykh opiatov s limfotsitami perifericheskoi krovi cheloveka.

The radioreceptor method and determination of the content of cAMP in lymphocytes were used to study the interplay of met-enkephalin with human peripheral blood lymphocytes. The characteristics of specific binding of endogenous opiate with the cells, as well s a decrease in the activity of lymphocyte adenylate cyclase observed under the effect of met-enkephalin proved the presence of a specific interplay between the physiological concentrations of the opiate with lymphocytes. It is suggested that it is determined by the existence of two parallel mechanisms: a process having some features in common with the receptor binding and limited transport of the opiate inside the cell.

[Clinical evaluation of the RKA 3-01 radiocardioanalyzer]. / Klinicheskaia otsenka radiokardioanalizatora RKA 3-01.

Detection of cardiovascular diseases can be improved through the use of the radiocardioanalyser RKA 3-01. It measures automatically the volume of circulating blood, records radiocardiograms, performs their analysis, and computes circulation indices.

[Immunomodulatory effects of selank in patients with anxiety-asthenic disorders].

The purpose of this article was to study the immunotropic effects of the new neurotrophic heptapeptide selank. The experiments in vitro revealed that the drug in concentration 10-7 M completely suppressed gene expression by peripheral blood IL-6 of patients with depression but not of the healthy controls. At the same time, the significant increase (p<0,05) of IL-6 concentration was observed in the cell culture of peripheral blood of patients in the presence of selank. The changes of the Th1/Th2 cytokine balance in vivo were found in the serum of patients with generalized anxiety disorder and neurasthenia who received Selank during 14 days. The dynamics of these changes had the significant inverse correlation dependence. The cytokine regulating effects revealed in the study suggest that selank can be used as a novel immunomodulator in patients with anxiety-asthenic disorders. Additionally, the adaptogenic properties of selank may be beneficial to its use in elderly people and people exposed to environmental stressors for the prevention of infectious diseases.

[Efficacy and possible mechanisms of action of a new peptide anxiolytic selank in the therapy of generalized anxiety disorders and neurasthenia].

Sixty-two patients with generalized anxiety disorder (GAD) and neurasthenia were studied. The effect of selank (30 patients) was compared to that of medazepam (32 patients). Patient's state was assessed with psychometric scales (Hamilton, Zung, CGI). Enkephalin activity in the blood serum was measured as well. The anxiolytic effects of both drugs were similar but selank had also antiasthenic and psychostimulant effects. The clinical-biological study revealed that patients with GAD and neurasthenia had the decreased level of tau(1/2) leu-enkephalin which was correlated with disease duration, severity of symptoms related to anxiety and asthenia and autonomic disorders. The increase of this parameter and stronger positive correlations with anxiety level were observed during the treatment with selank mostly in patients with GAD.

[Changes in rat liver mitochondria under conditions of bilateral subdiaphramatic vagotomy]. / Izmeneniia mitokhondrii pecheni krys v usloviiakh dvustoronnei poddiafragmal'noi vagotomii

A study was made of the changes in the mitochondria of the rat liver under conditions of bilateral subphrenic vagotomy. Two stages in the dynamics of the response of the mitochondrial apparatus to denervation were distingished. During the first stage (0.5-3 days after vagotomy) there occurred reversible functional disturbances of the mitochondria caused by the postoperative stress. The second stage (7 to 60 days after the denervation) was charaterized by more marked structural-functional changes having a number od common features with those seen in hypoxia and being result of vagotomy proper.

[Effect of vitamin E on the functional state of rat liver mitochondria following bilateral subdiaphragmatic vagotomy]. / Deistvie vitamin E na funktsional'noe sostoianie mitokhondrii pecheni krys posle dvustoronnei poddiafragmal'noi vagotomii

On the basis of a proven protective effect of vitamin "E" in regard to cellular metabolism in hypoxia and presuming that it is exactly the chronic hypoxia that forms the main pathogenetic link in the development of "deneravation changes" the effect of vitamin "E" on the function of hepatic metachondria in rats was studied polarographically and by using tetracycline, as a fluorescent probe, at different dates following bilateral subphrenic vagotomy. The available data prompted an inference of a marked stabilizing influence of the agent on the state of mitochondria in 7 and more days after vagotomy.

[Effect of morphine on the cAMP level of lymphocytes]. / Vliianie morfina na uroven' tsAMF v limfotsitakh.

A study was made of the effect of morphine on the cAMP level in peripheral blood lymphocytes in tobacco smoking and non-smoking donors. Morphine was shown to produce the naloxone-removable activation of adenylate cyclase, the relationship between enzymatic activity and opiate concentration in the medium being complex in nature. In tobacco smoking donors, the maximal effect on cAMP was produced by morphine at concentrations that were one order of magnitude higher than those in non-smoking ones. On the basis of the data obtained the assumptions are made (1) about the presence on the lymphocytes of opiate receptors whose action mode is associated with adenylate cyclase control, and (2) about the development during tobacco smoking of morphine tolerance at the level of opiate-dependent adenylate cyclase of lymphocytes.

[Interaction of thymosin fraction 3 with opiate receptors]. / Vzaimodeistvie tret'ei fraktsii timozina s opiatnymi retseptorami.

Using the radioreceptor method thymosin fraction 3 was demonstrated to displace 3H-morphine and 3H-naloxone from opiate receptor of crude membrane fraction of the rat brain. The value of EC50 ratio in the presence and absence of 100 mM NaCl seems to indicate that thymosin contains one or several partial agonists of morphine. Furthermore, the peptide nature of these ligands is suggested on the basis of enzymatic treatment data. The possible role of opioid peptides in the realization of thymus endocrine functions is discussed.

[Antenatal effect of imipramine on the ontogeny of the imipramine receptors in the cerebral cortex of rats]. / Antenatal'noe vliianie imipramina na ontogenez imipraminovykh retseptorov kory golovnogo mozga krys.

Ontogenetic study of imipramine binding sites in the rat brain cortex employing autoradiographic and radioreceptor methods revealed that they can be detected at the 19th day of gestation and that by the 14 day of postnatal development their amount reaches the adult levels. The affinity constants of imipramine binding sites did not change significantly throughout the ontogenetic development. Exposure to the therapeutic doses of imipramine on days 17-19 of gestation resulted in a significant increase in the amount of binding sites (24% of the control level) on day 3 of postnatal development, which returned to normal by the end of the second week of postnatal development. The distribution of imipramine binding sites in the cortical layers did not change either in normal rats or in those antenatally treated with imipramine.