title: Neonatal morphine exposure alters E-NTPDase activity and gene expression pattern in spinal cord and cerebral cortex of rats.
abstract: The neonate opioid system has been frequently investigated, and studies have shown that exposure to drugs in early life can have implications for nervous system development. It has been proposed that adenosine is involved in opioid antinociception, and ATP is involved in central and peripheral mechanisms of nociception. Extracellular nucleotides can be hydrolyzed by E-NTPDases and ecto-5'nucleotidase, which present the functions of removing ATP and generating adenosine. In this study, we evaluated ATP, ADP, and AMP hydrolysis in synaptosomes from spinal cord and cerebral cortex of rats at postnatal day 16 after repeated morphine exposure in early life (postnatal day 8 to 14). Additionally, we evaluated E-NTPDase (1, 2 and 3) and ecto-5'nucleotidase gene expression by semi-quantitative RT-PCR analysis. We observed an increase in ATP hydrolysis in the cerebral cortex, and a decrease in ADP hydrolysis in spinal cord. Expression levels of E-NTPDase 1 decreased in cerebral cortex and increased in spinal cord. Our findings highlight the importance of the purinergic system in young rats submitted to repeated morphine exposure by showing that in the neonatal period such exposure is capable of affecting the control system for nucleotide levels, which can promote changes in modulation or transmission of painful stimuli.
authors.affiliation: Laboratório de Farmacologia da Dor e da Inflamação, Departamento de Farmacologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Sarmento Leite, 500 sala 202, CEP 90050-170, Porto Alegre, Brazil.
authors.forename: Joanna Ripoll
authors.initials: JR
authors.lastname: Rozisky
authors.forename: Rosane Souza
authors.initials: RS
authors.lastname: da Silva
authors.forename: Lauren Spezia
authors.initials: LS
authors.lastname: Adachi
authors.forename: Katiucia Marques
authors.initials: KM
authors.lastname: Capiotti
authors.forename: Denise Barboza
authors.initials: DB
authors.lastname: Ramos
authors.forename: Maurício Reis
authors.initials: MR
authors.lastname: Bogo
authors.forename: Carla Denise
authors.initials: CD
authors.lastname: Bonan
authors.forename: João José Freitas
authors.initials: JJ
authors.lastname: Sarkis
authors.forename: Iraci Lucena da Silva
authors.initials: IL
authors.lastname: Torres
mesh_terms: D017766:Acid Anhydride Hydrolases / Q000235:genetics* / Q000378:metabolism*; D000818:Animals; D000831:Animals, Newborn; D002540:Cerebral Cortex / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D006801:Humans; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013116:Spinal Cord / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D013574:Synaptosomes / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D013997:Time Factors
chemical_list: D009020:Morphine; D017766:Acid Anhydride Hydrolases