PDA

View Full Version : Kindlundh, et al. (2003). Chronic administration with nandrolone decanoate induces alterations in the gene-transcript content of dopamine D(1)- and D(2)-receptors in the rat brain.


Wise Young
07-31-2003, 07:46 AM
• Kindlundh AM, Lindblom J and Nyberg F (2003). Chronic administration with nandrolone decanoate induces alterations in the gene-transcript content of dopamine D(1)- and D(2)-receptors in the rat brain. Brain Res 979:37-42. Summary: Some adolescent and young males are engaged in misuse of anabolic-androgenic steroids (AASs) in connection with multiple drug use, in order to become intoxicated and brave, apart from currently known motives connected to sports performance and physical appearance. Recent studies suggest that alterations in neurobiological circuits implicated in the regulation of reward-related learning, aggression and motoric behavior underlie the behavioral changes associated with AAS misuse. We have previously shown that AASs induce alterations in dopamine receptor densities. The aim of the present study was to investigate if these effects could be attributed to altered mRNA content for tyrosine hydroxylase, L-amino acid decarboxylase, dopamine D(1)- and dopamine D(2)-receptor as measured by in situ hybridisation. Male Sprague-Dawley rats were subjected to 2 weeks of treatment with daily intramuscular injections of the AAS nandrolone decanoate at three different doses (1, 5 and 15 mg/kg/day). Results of the in situ hybridization showed that the mRNA content of the dopamine D(1)-receptor subtype was significantly reduced at all doses in the caudate putamen and at the highest doses in the nucleus accumbens shell. The mRNA expression of the dopamine D(2)-receptor was significantly increased at the two lowest doses in the caudate putamen and the nucleus accumbens shell. In conclusion, nandrolone has been shown to affect the expression of gene transcripts of dopaminergic receptors possibly implicated in underlying mechanisms of reward-related behavioral changes among AAS misusers. Department of Pharmaceutical Biosciences, Division of Biological Research on Drug Dependence, Box 591, S-751-24, Uppsala, Sweden

Wise Young
07-31-2003, 07:54 AM
It also changes serotonergic receptors.


• Kindlundh AM, Lindblom J, Bergstrom L and Nyberg F (2003). The anabolic-androgenic steroid nandrolone induces alterations in the density of serotonergic 5HT1B and 5HT2 receptors in the male rat brain. Neuroscience 119:113-20. Summary: Anabolic-androgenic steroids (AAS) are partly misused by males in order to become brave and intoxicated and these agents are highly associated with psychosis, disinhibition, aggression and acts of violence. Since such behavioral states have been related to an imbalanced serotonergic system and the involvement of the serotonergic 5HT(1B) and the 5HT(2) receptors, it was important to discern the impact of AAS on these receptors. The objective of our study was to investigate the effects of 2 weeks of treatment with the AAS nandrolone decanoate at three different doses (1, 5, 15 mg/kg/day) on the total specific binding of the radioligands [(125)I]-(+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) (5HT(2) receptors) by autoradiography. All doses caused a significant down-regulation of the 5HT(1B) receptor density in the hippocampal CA(1) and in the medial globus pallidus and a significant up-regulation of the 5HT(2) receptor density in the nucleus accumbens shell. Alterations in receptor density were also observed in the lateral globus pallidus, ventromedial hypothalamus, the amygdala and in the intermediate layers of various cortex regions. In conclusion, serotonergic 5HT(1B) or 5HT(2) receptors are likely to play important roles in mediating observed emotional states and behavioral changes among AAS abusers. Department of Pharmaceutical Biosciences, Division of Biological Research on Drug Dependence, Box 591, S-751-24 Uppsala, Sweden. anna.kindlundh@farmbio.uu.se