alexa Primary reinforcing effects of nicotine are triggered from multiple regions both inside and outside the ventral tegmental area.
Pharmaceutical Sciences

Pharmaceutical Sciences

Biochemistry & Pharmacology: Open Access

Author(s): Ikemoto S, Qin M, Liu ZH

Abstract Share this page

Abstract Nicotine is thought to be the key substance responsible for tobacco-smoking habits and appears to trigger reinforcement via the ventral tegmental area (VTA). Recently, multiple anatomical substrates for drug reinforcement have been identified in the vicinity of the ventral midbrain. In addition to the posterior portion of the VTA, the central linear nucleus raphé and the supramammillary nucleus of the posterior hypothalamus mediate drug reinforcement. Using intracranial self-administration procedures, we examined whether these regions mediate the reinforcing effects of nicotine. Rats learned to lever press for self-administration of nicotine into the posterior VTA, central linear nucleus, and supramammillary nucleus, suggesting a reinforcing action of nicotine in these regions. The rats did not self-administer nicotine into surrounding regions including the anterior VTA, substantia nigra, the region just dorsal to the posterior VTA, interpeduncular nucleus, or medial mammillary nucleus. The reinforcing effects of nicotine into the three brain regions were further confirmed by a two-lever discrimination procedure, in which rats learned to selectively respond between active and inactive levers. The reinforcing effects of nicotine administration into the posterior VTA, central linear nucleus, and supramammillary nucleus were blocked by coadministration of the nicotine receptor antagonist mecamylamine. The reinforcing effects of nicotine into the posterior VTA or central linear nucleus were attenuated by coadministration of the D2 receptor agonist quinpirole. These findings demonstrate that nicotine reinforcement involves multiple regions both inside and outside the VTA.
This article was published in J Neurosci and referenced in Biochemistry & Pharmacology: Open Access

Relevant Expert PPTs

Relevant Speaker PPTs

Relevant Topics

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version