Abstract

The descending serotonergic neurons of nucleus raphe magnus have been proposed to play a crucial role in the expression of opiate and stimulation-produced analgesia. However, it is not clear what neurotransmitters might control the activity of this analgesia-producing system. The present proposal will examine that question by a combination of anatomical and electrophysiological means. The neurotransmitters adjacent to descending serotonergic neurons will be examined using a combination of retrograde labeling and two-color immunofluorescence. Additionally, the effects of these neurotransmitters on descending neurons will be examined using iontophoresis. These experiments will clarify how the activity of the serotonergic neurons within nucleus raphe magnus might be modulated.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Unknown (R23)
Project #
5R23NS022665-02
Application #
3449949
Study Section
Neurological Sciences Subcommittee 1 (NLS)
Project Start
1985-07-01
Project End
1988-06-30
Budget Start
1986-07-01
Budget End
1987-06-30
Support Year
2
Fiscal Year
1986
Total Cost
Indirect Cost

  Institution

Name
University of Minnesota Twin Cities
Department
Type
Schools of Medicine
DUNS #
168559177
City
Minneapolis
State
MN
Country
United States
Zip Code
55455

  Publications

Tallaksen-Greene, S J; Elde, R; Wessendorf, M W (1993) Regional distribution of serotonin and substance P co-existing in nerve fibers and terminals in the brainstem of the rat. Neuroscience 53:1127-42
Wessendorf, M W; Appel, N M; Molitor, T W et al. (1990) A method for immunofluorescent demonstration of three coexisting neurotransmitters in rat brain and spinal cord, using the fluorophores fluorescein, lissamine rhodamine, and 7-amino-4-methylcoumarin-3-acetic acid. J Histochem Cytochem 38:1859-77
Wessendorf, M W; Tallaksen-Greene, S J; Wohlhueter, R M (1990) A spectrophotometric method for determination of fluorophore-to-protein ratios in conjugates of the blue fluorophore 7-amino-4-methylcoumarin-3-acetic acid (AMCA) J Histochem Cytochem 38:87-94
Appel, N M; Wessendorf, M W; Elde, R P (1987) Thyrotropin-releasing hormone in spinal cord: coexistence with serotonin and with substance P in fibers and terminals apposing identified preganglionic sympathetic neurons. Brain Res 415:137-43
Wessendorf, M W; Appel, N M; Elde, R (1987) Simultaneous observation of fluorescent retrogradely labeled neurons and the immunofluorescently labeled fibers apposing them using Fluoro-Gold and antisera labeled with the blue fluorochrome 7-amino-4-methylcoumarin-3-acetic acid (AMCA). Neurosci Lett 82:121-6
Wessendorf, M W; Elde, R (1987) The coexistence of serotonin- and substance P-like immunoreactivity in the spinal cord of the rat as shown by immunofluorescent double labeling. J Neurosci 7:2352-63