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PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1999-3-25
pubmed:abstractText
The reproducibility of serotonin (5-HT) and (+)8-OH-DPAT-mediated inhibition of adenylyl cyclase activity was assessed in membranes, stimulated by forskolin, of rat frontal cortex postmortem as well as of human fronto-cortical, hippocampal and dorsal raphe tissues obtained from autopsy brains. The results revealed that differences between basal and forskolin-stimulated enzyme activities were still significant after 48 h postmortem in rat cortex and in all human brain regions up to 46 h after death. However, a decrease of about 17 and 26% in forskolin-stimulated adenylyl cyclase activity was observed at 24 and 48 h, respectively, in rat cortex. 5-HT and the 5-HT1A receptor agonist, (+)8-hydroxy-2(di-N-propylamino)tetraline (8-OH-DPAT), were able to inhibit forskolin-stimulated adenylyl cyclase activity in a dose-dependent manner for 48 h after death in rat and human brain. In rat cortex, both 5-HT and (+)8-OH-DPAT potencies (EC50, nM) and efficacies (percent of maximum inhibition capacity, %) varied significantly with postmortem delay. Conversely, in human tissues, postmortem delay and subject age did not modify agonist potencies and efficacies. Furthermore, a regionality of 5-HT potency and efficacy was revealed in the human brain. 5-HT was equally potent in cortex and raphe nuclei, while being more potent but less effective in hippocampus. (+)8-OH-DPAT was more active in hippocampus and raphe nuclei than in cortex. (+)8-OH-DPAT behaved as an agonist in all areas, as its efficacy was similar or greater than those obtained with 5-HT. The (+)8-OH-DPAT dose-response curve was completely reversed by 5-HT1A receptor antagonists in rat cortex and all human brain areas. In conclusion, we suggest here that differences between rat and human brain might exist at the level of postmortem degradation of 5-HT-sensitive adenylyl cyclase activity. In human brain, 5-HT1A receptor-mediated inhibition of adenylyl cyclase seems to be reproducible, suggesting that reliable experiments can be carried out on postmortem specimens from patients with neuropsychiatric disorders.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0006-8993
pubmed:author
pubmed:copyrightInfo
Copyright 1999 Elsevier Science B.V.
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
816
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
165-74
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:9878719-8-Hydroxy-2-(di-n-propylamino)tetralin, pubmed-meshheading:9878719-Adenylate Cyclase, pubmed-meshheading:9878719-Age Factors, pubmed-meshheading:9878719-Aged, pubmed-meshheading:9878719-Animals, pubmed-meshheading:9878719-Brain, pubmed-meshheading:9878719-Cerebral Cortex, pubmed-meshheading:9878719-Female, pubmed-meshheading:9878719-Forskolin, pubmed-meshheading:9878719-Frontal Lobe, pubmed-meshheading:9878719-Hippocampus, pubmed-meshheading:9878719-Humans, pubmed-meshheading:9878719-Male, pubmed-meshheading:9878719-Middle Aged, pubmed-meshheading:9878719-Postmortem Changes, pubmed-meshheading:9878719-Raphe Nuclei, pubmed-meshheading:9878719-Rats, pubmed-meshheading:9878719-Rats, Wistar, pubmed-meshheading:9878719-Receptors, Serotonin, pubmed-meshheading:9878719-Receptors, Serotonin, 5-HT1, pubmed-meshheading:9878719-Reproducibility of Results, pubmed-meshheading:9878719-Serotonin, pubmed-meshheading:9878719-Serotonin Receptor Agonists, pubmed-meshheading:9878719-Time Factors
pubmed:year
1999
pubmed:articleTitle
Effects of postmortem delay on serotonin and (+)8-OH-DPAT-mediated inhibition of adenylyl cyclase activity in rat and human brain tissues.
pubmed:affiliation
Department of 'Psichiatria, Neurobiologia, Farmacologia e Biotecnologie', University of Pisa, via Bonanno 6, I-56100, Pisa, Italy.
pubmed:publicationType
Journal Article