Lateral Hypothalamus Modifies Pain through Spinally-Projecting Serotonin Neurons in the Ventromedial Medulla

2.50
Hdl Handle:
http://hdl.handle.net/10755/160285
Type:
Presentation
Title:
Lateral Hypothalamus Modifies Pain through Spinally-Projecting Serotonin Neurons in the Ventromedial Medulla
Abstract:
Lateral Hypothalamus Modifies Pain through Spinally-Projecting Serotonin Neurons in the Ventromedial Medulla
Conference Sponsor:Midwest Nursing Research Society
Conference Year:2004
Author:Pizzi, Julie, BSN, RN
Contact Address:, 4107 N. Oakley #3, Chicago, IL, 60618, USA
Co-Authors:Julie A. Pizzi, BSN, RN; Janean E. Holden, PhD, RN, Assistant Professor
Pain is a problem that affects millions of Americans. As the primary care providers for clients with pain, nurses need to understand the underlying physiology of pain. Stimulation of the lateral hypothalamus (LH) electrically or chemically produces analgesia mediated in part by serotonin receptors in the spinal cord dorsal horn. Because most of the serotonin in the dorsal horn comes from neurons in the ventromedial medulla (VMM), we hypothesized that LH-induced analgesia occurs from synaptic contact between LH neurons and spinally-projecting neurons in the VMM. Based on preliminary results from our lab, we further hypothesized that substance P (SP) may be one neurotransmitter involved in this connection. To test these hypotheses, the cholinergic agonist carbachol (125 nmol) was microinjected into the LH of female Sprague-Dawley rats (250-360 g) to produce moderate analgesia on the tail flick test. Cobalt chloride (100 nmol, 0.2µl), which blocks all synaptic activity in the area of injection, was microinjected into the VMM and blocked analgesia compared to control animals (2.39 ± 0.14 vs. 4.36 ± 0.16 sec., p < 0.05). The SP receptor antagonist L-703,606 was microinjected into the VMM (8 nmol, 0.5µl) also blocked LH-induced analgesia compared to controls (2.18 ± 0.18 sec., p < 0.05). These data suggest that analgesia from LH stimulation is mediated in part by an SP connection between the LH and spinally descending neurons in the VMM, which has implications for the development of pain relief treatments.
Repository Posting Date:
26-Oct-2011
Date of Publication:
17-Oct-2011
Sponsors:
Midwest Nursing Research Society

Full metadata record

DC FieldValue Language
dc.typePresentationen_GB
dc.titleLateral Hypothalamus Modifies Pain through Spinally-Projecting Serotonin Neurons in the Ventromedial Medullaen_GB
dc.identifier.urihttp://hdl.handle.net/10755/160285-
dc.description.abstract<table><tr><td colspan="2" class="item-title">Lateral Hypothalamus Modifies Pain through Spinally-Projecting Serotonin Neurons in the Ventromedial Medulla</td></tr><tr class="item-sponsor"><td class="label">Conference Sponsor:</td><td class="value">Midwest Nursing Research Society</td></tr><tr class="item-year"><td class="label">Conference Year:</td><td class="value">2004</td></tr><tr class="item-author"><td class="label">Author:</td><td class="value">Pizzi, Julie, BSN, RN</td></tr><tr class="item-address"><td class="label">Contact Address:</td><td class="value">, 4107 N. Oakley #3, Chicago, IL, 60618, USA</td></tr><tr class="item-co-authors"><td class="label">Co-Authors:</td><td class="value">Julie A. Pizzi, BSN, RN; Janean E. Holden, PhD, RN, Assistant Professor </td></tr><tr><td colspan="2" class="item-abstract">Pain is a problem that affects millions of Americans. As the primary care providers for clients with pain, nurses need to understand the underlying physiology of pain. Stimulation of the lateral hypothalamus (LH) electrically or chemically produces analgesia mediated in part by serotonin receptors in the spinal cord dorsal horn. Because most of the serotonin in the dorsal horn comes from neurons in the ventromedial medulla (VMM), we hypothesized that LH-induced analgesia occurs from synaptic contact between LH neurons and spinally-projecting neurons in the VMM. Based on preliminary results from our lab, we further hypothesized that substance P (SP) may be one neurotransmitter involved in this connection. To test these hypotheses, the cholinergic agonist carbachol (125 nmol) was microinjected into the LH of female Sprague-Dawley rats (250-360 g) to produce moderate analgesia on the tail flick test. Cobalt chloride (100 nmol, 0.2&micro;l), which blocks all synaptic activity in the area of injection, was microinjected into the VMM and blocked analgesia compared to control animals (2.39 &plusmn; 0.14 vs. 4.36 &plusmn; 0.16 sec., p &lt; 0.05). The SP receptor antagonist L-703,606 was microinjected into the VMM (8 nmol, 0.5&micro;l) also blocked LH-induced analgesia compared to controls (2.18 &plusmn; 0.18 sec., p &lt; 0.05). These data suggest that analgesia from LH stimulation is mediated in part by an SP connection between the LH and spinally descending neurons in the VMM, which has implications for the development of pain relief treatments.</td></tr></table>en_GB
dc.date.available2011-10-26T22:47:54Z-
dc.date.issued2011-10-17en_GB
dc.date.accessioned2011-10-26T22:47:54Z-
dc.description.sponsorshipMidwest Nursing Research Societyen_GB
All Items in this repository are protected by copyright, with all rights reserved, unless otherwise indicated.