György Kóczán

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The possible mediating role of calcitonin gene-related peptide (CGRP) in the effects of capsaicin in the guinea-pig ileum has been investigated by means of the CGRP antagonist hCGRP(8-37). Submaximal longitudinal muscle relaxation of the histamine-precontracted ileum evoked by rat CGRP (3 nM) or capsaicin (1 microM) was reversed by hCGRP(8-37) (1.5 microM),(More)
Inhibitors of nitric oxide (NO) synthase inhibit nerve-mediated non-adrenergic, non-cholinergic (NANC) smooth muscle relaxation in the gastrointestinal tract. In this study, the effect of a NO synthase inhibitor, NG-nitro-L-arginine, was examined on the tetrodotoxin-sensitive NANC contractile response of the rat isolated ileal myenteric plexus-longitudinal(More)
Both the neuropeptide calcitonin gene-related peptide (CGRP) and the sensory stimulant drug capsaicin exert excitatory as well as inhibitory actions in the guinea-pig ileum. It has been known that their excitatory effects are due to activation of myenteric neurons. In the present study it has been established that a fairly high concentration (3 microM) of(More)
A proteolytic enzyme, Php-B ( Photorhabdus protease B), was purified from the entomopathogenic bacterium, Photorhabdus luminescens. The enzyme is intracellular, and its molecular mass is 74 kDa. Tested on various peptide and oligopeptide substrates, Php-B hydrolysed only oligopeptides, with significant activity against bradykinin and a(More)
his review will summarize available information on the ability of macromolecular conjugates containing no specific recognition motifs to deliver anthracyclines (daunomycin, adriamycin) or methotrexate to target cells such as tumour cells or macrophages. Conjugates with natural (proteins, DNA, carbohydrates) and synthetic macromolecules (linear and branched(More)
Methotrexate (MTX) has been coupled to various structurally related, polycationic (poly[Lys(DL-Ala(m))] (AK), poly[Lys(Ser(i)-DL-Ala(m))] (SAK), poly[Lys(DL-Ala(m)-Leu(i))] (ALK)), or amphoteric (poly[Lys(Glu(i)-DL-Ala(m))] (EAK)) synthetic branched polypeptides containing poly[L-Lys] backbone by the aid of BOP reagent. The average degree of MTX(More)
The authors analyse the modelling effect of the suicide of the first Hungarian beauty queen. After the publication of a book, a film and the newspapers about her suicide increased significantly the number of suicides committed by young females by the same method (Lidocain pill). During this period the consumption of Lidocain pills decreased in Hungary. The(More)
Methotrexate (MTX) conjugates with poly[Lys(DL-Alam)] based polymeric polypeptides are efficient against Leishmania donovani parasite infection, but the mechanism of the effect is not known yet. We prepared therefore the 5(6)-carboxyfluorescein (Cf) labeled oligopeptide [Cf-K(AaAa)] (a: D-alanine, A: L-alanine) and the corresponding MTX conjugates(More)
Panic agoraphobic subjects constantly struggle with the accurate registration of everyday space-time dimension. They are hindered in the exploration of their surroundings by constant self-directed attention. In our investigations we examined whether during experimental goal-directed locomotion orientation insecurity would appear. The accuracy of(More)
Strategies for the preparation of new fluorescent oligopeptide conjugates labeled with 4-ethoxymethylene-2-[1]-naphthyl-5(4H)-oxazolone (naOx-OEt) at the N-terminal on solid support or in solution have been devised. These procedures are simple and easy to carry out by reacting naOx-OEt or N(alpha)-naOx-amino acid with side chain protected peptide chains(More)