The Korean Journal of Pain
- Volume 14 Issue 2
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- Pages.225-230
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- 2001
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- 2005-9159(pISSN)
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- 2093-0569(eISSN)
Supraspinal Nitric Oxide Synthesis Inhibition Enhanced Antinociception of Morphine in Morphine Tolerant Rats
모르핀내성시 뇌실내 NO 합성억제제 투여가 모르핀의 진통효과에 미치는 형향
- Song, Ho-Kyung (Department of Anesthesiology, College of Medicine, The Catholic University of Korea) ;
- Jang, Yeon (Department of Anesthesiology, College of Medicine, The Catholic University of Korea)
- Published : 2001.12.30
Abstract
Background: Opioids such as morphine are widely used in the treatment for pain, but chronic treatment with morphine can be complicated by the development of tolerance. The mechnisms of tolerance were still not completely understood, but recently it has been reported that NOS inhibitors can prevent development of morphine tolerance in animals. The present study accessed the possible role of supraspinal NO on antinociceptive effect of morphine in morphine tolerance using a highly specific inhibitor of the neuronal isoform of NOS, 1-(2-trifluoromethylphenyl) imidazole (TRIM). Methods: Thirty two male SD rats (300 g) were prepared with intracerebroventricular (icv) and IV cannulae. We administrated IV morphine, 3 mg/kg, daily for 4 days, resulting in tolerance. On the fifth day, a challenge dose of morphine, 3 mg/kg, was administered following pretreatment with icv TRIM,