Chronic methamphetamine affects prodynorphin gene expression in rat brain

Romualdi, Patrizia; Donatini, A.; Ferri, Simona

doi:10.1016/1043-6618(95)86704-x

Cited by 2 publications

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“…Alterations at the gene and protein expression levels with mu-opioid receptors and the synaptic, cellular, and circuit levels may underlie drug tolerance and dependence (3,9,10). Tolerance to morphine also involves alterations in the endogenous opioid peptides (11).…”

Section: Introductionmentioning

confidence: 99%

Region Specificity in Endogenous Opioid Peptides and Mu-opioid Receptor Gene Expression in Rat Brain Areas Involved in Addiction After Frequent Morphine Treatment

Ahmadi

Masoudi

Talvar

et al. 2022

Jentashapir J Cell Mol Biol

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Backgrounds: Molecular mechanisms involved in adverse effects of morphine, including tolerance and dependence, have remained elusive. We examined possible alterations in the gene expression of proenkephalin (Penk), prodynorphin (Pdyn), and mu-opioid receptor (Oprm1) in reward brain areas following frequent morphine treatment. Methods: Two groups of male Wistar rats were used. The groups received either saline (1 mL/kg) or morphine (10 mg/kg) twice daily for eight days. On day 8, rats were decapitated, brain areas involved in addiction were dissected, including the midbrain, striatum, prefrontal cortex (PFC), hippocampus, and hypothalamus, and gene expression was evaluated with real-time PCR. Results: Prolonged morphine treatment decreased Penk, Pdyn, and Oprm1 gene expressions in the midbrain but upregulated them in the striatum compared to the control group treated with saline. Significant increases in Pdyn and Oprm1 gene expressions were detected in the PFC, but there was no significant difference in Penk gene expression between the two groups. Besides, Pdyn gene expression was decreased in the hippocampus and hypothalamus; however, no significant differences in Penk and Oprm1 gene expressions were detected between the groups in these areas. Conclusions: The expression of endogenous opioid peptides and receptors after frequent use of morphine follows a region specificity in brain areas involved in addiction. These alterations may result in new physiological setpoints outside the normal range, which need to be considered when using morphine in medicine.

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Section: Introductionmentioning

confidence: 99%

Region Specificity in Endogenous Opioid Peptides and Mu-opioid Receptor Gene Expression in Rat Brain Areas Involved in Addiction After Frequent Morphine Treatment

Ahmadi

Masoudi

Talvar

et al. 2022

Jentashapir J Cell Mol Biol

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“…(Buzas et al 1996; Garcia de Yebenes & Pelletier 1993; Georges et al 1999; Romualdi et al 1990, 1991; Trujillo et al 1995; Yukhananov et al 1993)) and the dopaminergic system (Spangler et al 2003). In the nucleus accumbens and caudate putamen of rats, Penk mRNA levels were decreased by chronic administration of morphine (Basheer & Tempel 1993; Georges et al 1999; Uhl et al 1988).…”

Section: : Introductionmentioning

confidence: 99%

Regional mRNA expression of the endogenous opioid and dopaminergic systems in brains of C57BL/6J and 129P3/J mice: Strain and heroin effects

Schlussman¹,

Cassin²,

Zhang³

et al. 2011

Pharmacology Biochemistry and Behavior

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We have previously shown strain and dose differences in heroin-induced behavior, reward and regional expression of somatostatin receptor mRNAs in C57BL/6J and 129P3/J mice. Using Real Time PCR we examined the effects of five doses of heroin on the levels of the transcripts of endogenous opioid peptides and their receptors and dopaminergic receptors in the mesocorticolimbic and nigrostriatal pathways in these same mice. Compared to C57BL/6J animals, 129P3/J mice had higher mRNA levels of Oprk1 in the nucleus accumbens and of Oprd1 in the nucleus accumbens and a region containing both the substantia nigra and ventral tegmental area (SN/VTA). In the cortex of 129P3/J mice, lower levels of both Oprk1 and Oprd1 mRNAs were observed. Pdyn mRNA was also lower in the caudate putamen of 129P3/J mice. Strain differences were not found in the levels of Oprm1, Penk or Pomc mRNAs in any region examined. Within strains, complex patterns of heroin dose-dependent changes in the levels of Oprm1, Oprk1 and Oprd1 mRNAs were observed in the SN/VTA. Additionally, Oprd1 mRNA was dose-dependently elevated in the hypothalamus. Also in the hypothalamus, we found higher levels of Drd1a mRNA in C57BL/6J mice than in 129P3/J animals and higher levels of DAT (Slc6a3) mRNA in the caudate putamen of C57BL/6J animals than in 129P3/J counterparts. Heroin had dose-related effects on Drd1a mRNA in the hypothalamus and on Drd2 mRNA in the caudate putamen.

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Chronic methamphetamine affects prodynorphin gene expression in rat brain

Cited by 2 publications

References 0 publications

Region Specificity in Endogenous Opioid Peptides and Mu-opioid Receptor Gene Expression in Rat Brain Areas Involved in Addiction After Frequent Morphine Treatment

Region Specificity in Endogenous Opioid Peptides and Mu-opioid Receptor Gene Expression in Rat Brain Areas Involved in Addiction After Frequent Morphine Treatment

Regional mRNA expression of the endogenous opioid and dopaminergic systems in brains of C57BL/6J and 129P3/J mice: Strain and heroin effects

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