Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1991-3-8
pubmed:abstractText
Intraneuronal peptide regulatory mechanisms are still poorly understood. The cytosolic enzymes prolyl endopeptidase (EC 3.4.21.26) and pyroglutamyl peptidase I (E.C.3.4.19.3) degrade both TRH and LHRH. Previous studies from this laboratory have not supported a role for these enzymes in the control of TRH levels. These studies have now been extended to cell and organ cultures and examine the effects of enzyme inhibition on LHRH. Exposure of dispersed hypothalamic cells or median eminences in culture to Z-Pro-Prolinal and pyroglutamyl diazomethyl ketone, specific inhibitors of prolyl endopeptidase and pyroglutamyl peptidase I respectively, did not change TRH content or recovery of released TRH. In vivo and in vitro treatment with these inhibitors did not modify the content of LHRH or recovery of this peptide upon release from several brain regions except in the olfactory bulb where an unexpected decrease in levels was observed. Olfactory bulb levels of TRH also decreased but only after prolonged in vivo inhibitor treatment. The decrease in olfactory bulb LHRH and TRH could not be accounted for by enzyme induction and is likely due to a non-specific or indirect effect of the inhibitors on the processing of these peptides. These studies demonstrate that levels of LHRH and TRH in brain are not controlled by cytosolic peptidases.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0143-4179
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
55-62
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:1980725-Animals, pubmed-meshheading:1980725-Brain, pubmed-meshheading:1980725-Cells, Cultured, pubmed-meshheading:1980725-Dipeptides, pubmed-meshheading:1980725-Embryo, Mammalian, pubmed-meshheading:1980725-Endopeptidases, pubmed-meshheading:1980725-Gonadotropin-Releasing Hormone, pubmed-meshheading:1980725-Hypothalamus, pubmed-meshheading:1980725-Male, pubmed-meshheading:1980725-Median Eminence, pubmed-meshheading:1980725-Mice, pubmed-meshheading:1980725-Olfactory Bulb, pubmed-meshheading:1980725-Organ Culture Techniques, pubmed-meshheading:1980725-Pyroglutamyl-Peptidase I, pubmed-meshheading:1980725-Pyrrolidonecarboxylic Acid, pubmed-meshheading:1980725-Rats, pubmed-meshheading:1980725-Rats, Inbred Strains, pubmed-meshheading:1980725-Serine Endopeptidases, pubmed-meshheading:1980725-Thyrotropin-Releasing Hormone
pubmed:year
1990
pubmed:articleTitle
Evaluation of the role of prolyl endopeptidase and pyroglutamyl peptidase I in the metabolism of LHRH and TRH in brain.
pubmed:affiliation
Departamento de Bioquimica de Proteinas, Universidad Nacional Autonoma de Mexico, Cuernavaca Mor.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't