213 118 118 4 4 R. J. Vermeulen B. Drukarch E. C. Wolters J. C. Stoof A. N. M. Schoffelmeer M. C. Rob Sahadat C. Goosen Department of Neurology, Medical Faculty Graduate School Neurosciences Amsterdam, Research Institute Neurosciences Vrije Universiteit Van der Boechorststraat 7 NL-1081 BT Amsterdam The Netherlands Department of Pharmacology, Medical Faculty Graduate School Neurosciences Amsterdam, Research Institute Neurosciences Vrije Universiteit Van der Boechorststraat 7 NL-1081 BT Amsterdam The Netherlands TNO Medical Biological Laboratory NL-Rijswijk The Netherlands Abstract Interactions at the behavioral level between dopamine (DA) and opioid receptors in the mammalian brain have been amply demonstrated. Considering the pivotal role for DA receptors in the pharmacotherapy of Parkinson's disease (PD), these interactions might be clinically relevant. Therefore, in the present study the effects of the opioid antagonist naltrexone and agonist morphine on D 1 and D 2 receptor induced stimulation of motor behavior in the unilateral MPTP monkey model ( n =5) of PD were investigated. The results show that both naltrexone and morphine (0.1–1.0 mg/kg; intramuscular injection (IM)) inhibited D 2 receptor stimulated contralateral rotational behavior and hand use induced by administration of quinpirole (LY 171555; 0.01 mg/kg, IM) in a dose-related way. However, no effects of these opioid drugs were observed on D 1 receptor stimulated contralateral rotational behavior and hand use induced by administration of SKF 81297 (0.3 mg/kg, IM). Interestingly, the action of the alleged preferential μ -receptor antagonist naltrexone was mimicked by the selective δ -opioid antagonist naltrindole (0.5 mg/kg, IM). From this study it is concluded that in a non-human primate model of PD, alteration of opioid tonus leads to modulation of D 2 receptor but not D 1 receptor controlled motor behavior. The possible underlying mechanisms and clinical relevance of these findings are discussed.
Psychopharmacology – Springer Journals
Published: Apr 1, 1995
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera