QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

This Article Full Text Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (25) Citing Articles via Google Scholar Google Scholar Articles by Simmons, J. M. Articles by Gallistel, C. R. Search for Related Content PubMed PubMed Citation Articles by Simmons, J. M. Articles by Gallistel, C. R.

 Previous Article  |  Next Article 

The Journal of Neuroscience, October 15, 1998, 18(20):8515-8533

Medial Forebrain Bundle Lesions Fail to Structurally and Functionally Disconnect the Ventral Tegmental Area from Many Ipsilateral Forebrain Nuclei: Implications for the Neural Substrate of Brain Stimulation Reward

Janine M. Simmons, Robert F. Ackermann, and C. R. Gallistel

Brain Research Institute, University of California Los Angeles, Los Angeles, California 90095

Lesions in the medial forebrain bundle rostral to a stimulating electrode have variable effects on the rewarding efficacy of self-stimulation. We attempted to account for this variability by measuring the anatomical and functional effects of electrolytic lesions at the level of the lateral hypothalamus (LH) and by correlating these effects to postlesion changes in threshold pulse frequency (pps) for self-stimulation in the ventral tegmental area (VTA). We implanted True Blue in the VTA and compared cell labeling patterns in forebrain regions of intact and lesioned animals. We also compared stimulation-induced regional [¹⁴C]deoxyglucose (DG) accumulation patterns in the forebrains of intact and lesioned animals. As expected, postlesion threshold shifts varied: threshold pps remained the same or decreased in eight animals, increased by small but significant amounts in three rats, and increased substantially in six subjects. Unexpectedly, LH lesions did not anatomically or functionally disconnect all forebrain nuclei from the VTA. Most septal and preoptic regions contained equivalent levels of True Blue label in intact and lesioned animals. In both intact and lesioned groups, VTA stimulation increased metabolic activity in the fundus of the striatum (FS), the nucleus of the diagonal band, and the medial preoptic area. On the other hand, True Blue labeling demonstrated anatomical disconnection of the accumbens, FS, substantia innominata/magnocellular preoptic nucleus (SI/MA), and bed nucleus of the stria terminalis. [¹⁴C]DG autoradiography indicated functional disconnection of the lateral preoptic area and SI/MA. Correlations between patterns of True Blue labeling or [¹⁴C]deoxyglucose accumulation and postlesion shifts in threshold pulse frequency were weak and generally negative. These direct measures of connectivity concord with the behavioral measures in suggesting a diffuse net-like connection between forebrain nuclei and the VTA.

Key words: brain stimulation reward; medial forebrain bundle; [¹⁴C]deoxyglucose autoradiography; True Blue; lateral hypothalamic lesions; VTA stimulation; reward pathway; self-stimulation

---

Copyright © 1998 Society for Neuroscience  0270-6474/98/18208515-19$05.00/0

This article has been cited by other articles:

				L. Velisek, J. Veliskova, O. Chudomel, K.-L. Poon, K. Robeson, B. Marshall, A. Sharma, and S. L. Moshe Metabolic Environment in Substantia Nigra Reticulata Is Critical for the Expression and Control of Hypoglycemia-Induced Seizures J. Neurosci., September 17, 2008; 28(38): 9349 - 9362. [Abstract] [Full Text] [PDF]

				E. Stemmy Inaugural Article: Biography of Charles R. Gallistel PNAS, September 7, 2004; 101(36): 13121 - 13123. [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help