Abstract
The researchers studied whether 2 separate motivational systems in the brain underlie the rewarding effects of morphine. The brainstem tegmental pedunculopontine nucleus (TPP) is involved in mediating the motivational effects of opiates in nondeprived (drug-naive) rats, whereas dopamine transmission is necessary in mediating the motivational effects of opiates in deprived rats (opiate withdrawal). The results show that heroin's motivational properties obey the same boundary between a nondeprived and a deprived motivational state. Bilateral ibotenic acid lesions of the TPP blocked the acquisition of a place preference for an environment paired with 0.05 mg/kg heroin (a dose that induces no withdrawal aversion) but had no effect on place preference for an environment paired with 0.5 mg/kg heroin (a dose that does induce withdrawal aversion). Dopamine antagonist pretreatment produced the opposite pattern of results.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.