RESUMO
Minute amounts of cerebrospinal fluid samples from alcoholics were subjected to separation by HPLC-molecular sieving, combined with multispectral UV analysis of the acquired data. A significant difference in the protein/polypeptide pattern within the molecular weight range of 7-10 kDa has been observed between samples, taken directly after detoxification and 2 weeks later. Spectral analysis of the results suggests that the components are of peptidergic nature. On the other hand, albumin content did not differ significantly, suggesting that the blood-brain barrier was not affected. An enzyme marker, dynorphin converting enzyme, remained unchanged in both groups.
Assuntos
Alcoolismo/líquido cefalorraquidiano , Proteínas do Líquido Cefalorraquidiano/análise , Cromatografia Líquida de Alta Pressão/métodos , Adulto , Idoso , Albuminas/líquido cefalorraquidiano , Cromatografia em Gel , Cistatina C , Cistatinas/líquido cefalorraquidiano , Humanos , Pressão Intracraniana , Masculino , Pessoa de Meia-Idade , Peso Molecular , Espectrofotometria Ultravioleta , Microglobulina beta-2/líquido cefalorraquidianoRESUMO
Two cysteine proteinases, cleaving dynorphins A and B to enkephalins, were isolated from the human spinal cord. These enzymes were found to be competitively inhibited by a new class of synthetic inhibitors: N-peptidyl-O-acyl hydroxylamines. The most potent (Ki < 20 microM) were the N-terminally protected peptides Z-Phe-Phe-NHO-Ma and Boc-Phe-Gly-NHO-Bz, both containing hydrophobic amino acids at the P2 position. N-Peptidyl-O-acyl hydroxylamines were converted in water solution to the corresponding hydroxamic acids and no cleavage of the peptide bond within the inhibitor sequence was observed after prolonged incubation with the enzymes. It is anticipated that these synthetic compounds may serve as potential pharmacological tools for in vitro studies on dynorphin processing.