سامانه همایش های دانشگاه آزاد اسلامی واحد نجف آباد

صفحه اصلی / اولین همایش بین المللی تحول خدمات سلامت: تلفیق مراقبت، درمان، بازتوانی و امیدبخشی

Prevention of Morphine-Induced Inhibition of Lateral Habenula Neurons via GABAB Receptors Blockade in Rat: An Electrophysiological Study

نویسندگان :

Elahe Amohashemi¹ Parham Reisi² Hojjatallah Alaee³

1- دانشگاه علوم پزشکی اصفهان 2- دانشگاه علوم پزشکی اصفهان 3- دانشگاه علوم پزشکی اصفهان

کلمات کلیدی :

Extracellular recording،GABAB receptors،Lateral habenula،Morphine

چکیده :

Background: The lateral habenula (LHb), a key area in the regulation of the reward system, exerts a major influence on midbrain neurons. It has been shown that the gamma-aminobutyric acid (GABA)-ergic system plays the main role in morphine dependency. The role of GABA type B receptors (GABABRs) in the regulation of LHb neural activity in response to morphine, remain unknown. In this study, the effect of GABABRs blockade in response to morphine was assessed on the neuronal activity in the LHb. Method: Baseline firing rate was recorded for 15 min, then morphine (5 mg/kg; s.c) and phaclofen (0, 0.5, 1 and 2 µg/rat), a GABABRs’ antagonist, were microinjected into the LHb. Their effects on the firing of LHb neurons were investigated in male rats, using an extracellular single-unit recording Finding: The results revealed that morphine decreased the neuronal activity, and GABABRs blockade alone did not have any effect on the neuronal activity of the LHb, but blockading with doses of 1 and 2 µg/rat of the antagonist could significantly prevent the inhibitory effects of morphine on the LHb neuronal activity Conclusion: The results show that although GABABR blockade alone has no effect on neuronal activity in LHb, it prevents the inhibitory effects of morphine on neuronal activity in this nucleus. Therefore, we proposed that GABABRs have a potential modulator effect, in response to morphine in the LHb . Methods: Baseline firing rate was recorded for 15 min, then morphine (5 mg/kg; s.c) and phaclofen (0, 0.5, 1 and 2 µg/rat), a GABABRs’ antagonist, were microinjected into the LHb. Their effects on the firing of LHb neurons were investigated in male rats, using an extracellular single-unit recording results : The results revealed that morphine decreased the neuronal activity, and GABABRs blockade alone did not have any effect on the neuronal activity of the LHb, but blockading with doses of 1 and 2 µg/rat of the antagonist could significantly prevent the inhibitory effects of morphine on the LHb neuronal activity Conclusion: The results show that although GABABR blockade alone has no effect on neuronal activity in LHb, it prevents the inhibitory effects of morphine on neuronal activity in this nucleus. Therefore, we proposed