en The effects of intra-locus coeruleus injection of dopamine D1 receptor agents on naloxone-induced withdrawal signs Experimental research article Experimental research article <b><font face="TimesNewRomanPS-BoldMT" size="2"><p align="left">I Mirzaii Dizgah</p></font><font face="TimesNewRomanPS-BoldMT" size="1">1</font><font face="TimesNewRomanPS-BoldMT" size="2">, SM Karimian</font><font face="TimesNewRomanPS-BoldMT" size="1">1</font><font face="TimesNewRomanPS-BoldMT" size="2">, MR Zarrindast</font><font face="TimesNewRomanPS-BoldMT" size="1">2</font><font face="TimesNewRomanPS-BoldMT" size="2">, H Sohanaki</font><font face="TimesNewRomanPS-BoldMT" size="1">1</font><i><font face="TimesNewRomanPS-BoldItalicMT" size="2"><p align="left">1. Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.</p><p align="left">2. Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.</p></font><font face="TimesNewRomanPS-BoldMT" size="3"><p align="left">Abstract:</p></font><font face="TimesNewRomanPSMT" size="3"><p align="left">Opiate-induced addiction is one of the main problems of mankind societies and its treatment is one of the health</p><p align="left">priorities of community. Therefore, relative studies would be very crucial. The exact mechanism of dependence</p><p align="left">to opiates and their withdrawal syndrome remain unclear. It seems that dopaminergic system and locus coeruleus</p><p align="left">(LC) have an important role in the somatic signs expression of opioids withdrawal syndrome. In the present</p><p align="left">study, the effects of different D1 dopaminergic receptor agonist and antagonist administration into the LC on the</p><p align="left">expression of withdrawal signs of morphine dependence in rats were studied.</p><p align="left">Rats were divided into 8 groups (n=8). Two cannulae were stereotaxically implanted bilaterally into the LC. After</p><p align="left">1 weak recovery, 7 groups rendered dependent to morphine (subcutaneously) during a 7 day period and nondependent</p><p align="left">animals were received saline with the same protocol. Animals received bilateral intra-LC injections of</p><p align="left">saline, SKF38393 (D1 agonist) or SCH23390 (D1 antagonist) before naloxone injection about 24 hours after the</p><p align="left">last dose of morphine or saline. Total withdrawal score as an index of withdrawal syndrome were decreased by</p><p align="left">SKF38393 (2, 4 μg/site) but not by SCH23390. It is concluded that the D1 dopaminergic system in the LC may</p><p align="left">be involved in the morphine induced dependency in rats.</p></font><b><font face="TimesNewRomanPS-BoldMT" size="3"><p align="left">Keywords: </p><p align="left">SCH23390.</p></font><font face="TimesNewRomanPSMT" size="3">Withdrawal Syndrome, Dopamine, Morphine, dependence, Naloxone, Locus coeruleus, SKF38393,</font><font face="TimesNewRomanPSMT" size="1"><p align="left">Physiology and Pharmacology</p></font><font face="TimesNewRomanPSMT" size="4"><p align="left">7</p></font></b></i></b> 167 172 http://ppj.phypha.ir/browse.php?a_code=A-10-1-20&slc_lang=en&sid=1