Khorasani Mahdi Zahedi, Hajizadeh Sohrab, Fathollahi Yaghoub, Semnanian Saeed
Physiological Research Centre, Semnan University of Medical Sciences, P.O. Box 35195-163, Semnan, Iran.
Brain Res. 2006 Apr 21;1084(1):61-6. doi: 10.1016/j.brainres.2006.01.106. Epub 2006 Apr 13.
The present research aimed at investigating the opioid-adenosine interaction on regional cerebral blood flow (rCBF). Therefore rCBF in the sensory cortex of morphine-naive and -dependent rats was measured using the laser-Doppler flowmetry technique. The results showed that adenosine (10(-5), 10(-4), 10(-3) M) significantly increased rCBF in morphine-dependent rats (MDR) (P < 0.01). This effect was inhibited by theophylline (5 x 10(-5) M). Also systemic naloxone (0.5, 1.5 and 3 mg/kg, s.c.) significantly increased rCBF in MDR and it was accompanied by elevated blood pressure and heart rate. Local adenosine (10(-4) M) significantly augmented naloxone (0.5 mg/kg)-induced increase in rCBF of MDR but had no significant effect on naloxone's (1.5 and 3 mg/kg) increasing effect on rCBF. Theophylline also has no effect on naloxone increasing effect on rCBF. These data suggest that adenosine receptors responsiveness increase in sensory cortex of MDR. Naloxone also highly increased rCBF of MDR that probably not interfere with adenosine receptors. Also, it seems that adenosine acts as a modulator in rCBF regulation of morphine-dependent and morphine withdrawal rats.
本研究旨在探讨阿片类药物与腺苷对局部脑血流（rCBF）的相互作用。因此，采用激光多普勒血流仪技术测量了未使用过吗啡和吗啡依赖大鼠感觉皮层的rCBF。结果显示，腺苷（10⁻⁵、10⁻⁴、10⁻³ M）可显著增加吗啡依赖大鼠（MDR）的rCBF（P < 0.01）。这种作用被茶碱（5×10⁻⁵ M）抑制。同样，全身给予纳洛酮（0.5、1.5和3 mg/kg，皮下注射）可显著增加MDR的rCBF，并伴有血压和心率升高。局部给予腺苷（10⁻⁴ M）可显著增强纳洛酮（0.5 mg/kg）诱导的MDR的rCBF增加，但对纳洛酮（1.5和3 mg/kg）增加rCBF的作用无显著影响。茶碱对纳洛酮增加rCBF的作用也无影响。这些数据表明，MDR感觉皮层中腺苷受体的反应性增加。纳洛酮也可显著增加MDR的rCBF，这可能与腺苷受体无关。此外，腺苷似乎在吗啡依赖和吗啡戒断大鼠的rCBF调节中起调节作用。
