ristocetin and actinoidins

The structures of ristomycin and actinoidine amino acids described earlier were revised. Crystalline derivatives of the amino acids and the products of their oxidation were prepared. The study on the spectral properties of the compounds showed that ristomycin and actinoidine amino acids had the structures of 3-(2'-hydroxy-5'-glycyl-phenoxy)-4-methyl-5-hydroxyphenylglycine and 2-(2'-hydroxy-5'-glycyl-phenyl)-3,5-dioxyphenylglycine respectively. They did not differ from deaminodicarboxylic acids prepared with ristocetin, vancomycin and actionoidine.

Topics: Chemical Phenomena; Chemistry; Electron Spin Resonance Spectroscopy; Ristocetin; Spectrophotometry, Ultraviolet; Vancomycin

Topics: Adenosine Diphosphate; Animals; Cattle; Collagen; Epinephrine; Factor VIII; Glycopeptides; Humans; Platelet Aggregation; Ristocetin; Thrombin; Vancomycin

The effect of 4 vancomycin antibiotics on factor VIII-dependent agglutination of thrombocytes was studied. Significant similarity, both quantitative and qualitative, between ristocetin and ristomycin was found. In this connection ristomycin may be used for determination of the so-called ristocetin cofactor. Actinoidin and vancomycin inhibited agglutination of platelets induced by ristocetin or ristomycin in platelet-enriched plasma with citrate or EDTA the same as in the system contaning platelets treated with formalin and did not inhibit agglutination induced by the bovine factor VIII. The 4 antibiotics induced precipitation of the plasma protein. Vancomycin was most active and actinoidin ws lest active in this respect. Ristocetin and ristomycin also possessed such capacity, the effect of the latter being higher. Actinoidin and vancomycin did not prevent the immediate effect of light absorption increasing due to addition of ristocetin or ristomycin to fixed platelets in concentrations completely inhibiting agglutination of platelets in the presence of the protein cofactor. Inhibition of this direct effect of ristocetin and ristomycin was observd only at higher concentrations, which indicated that this effect was not probably associated with agglutination. The results of the study on various ristomycin derivatives showed that methylated carboxylic groups and free hydroxyls of phenol may play the main role in ristomycin binding with the thrombocytic membrane and/or protein cofactor.

Topics: Dose-Response Relationship, Drug; Drug Interactions; Factor VIII; Female; Humans; Male; Platelet Aggregation; Ristocetin; Structure-Activity Relationship; Vancomycin

Topics: Agglutination; Blood Platelets; Blood Proteins; Chemical Precipitation; Citrates; Edetic Acid; Formaldehyde; Glycopeptides; Humans; Platelet Aggregation; Ristocetin; Vancomycin