Format

Send to

Choose Destination
PLoS One. 2016 Feb 25;11(2):e0150164. doi: 10.1371/journal.pone.0150164. eCollection 2016.

Mechanical Conflict System: A Novel Operant Method for the Assessment of Nociceptive Behavior.

Author information

1
Department of Anesthesiology, Chronic Pain and Fatigue Research Center, University of Michigan, Ann Arbor, Michigan, United States of America.
2
Department of Internal Medicine, Division of Rheumatology, University of Michigan, Ann Arbor, Michigan, United States of America.
3
Neurology Service, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan, United States of America.
4
Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America.
5
Department of Physiology, University of Kentucky, Lexington, Kentucky, United States of America.
6
Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, Kentucky, United States of America.

Abstract

A new operant test for preclinical pain research, termed the Mechanical Conflict System (MCS), is presented. Rats were given a choice either to remain in a brightly lit compartment or to escape to a dark compartment by crossing an array of height-adjustable nociceptive probes. Latency to escape the light compartment was evaluated with varying probe heights (0, .5, 1, 2, 3, and 4 mm above compartment floor) in rats with neuropathic pain induced by constriction nerve injury (CCI) and in naive control rats. Escape responses in CCI rats were assessed following intraperitoneal administration of pregabalin (10 and 30 mg/kg), morphine (2.5 and 5 mg/kg), and the tachykinin NK1 receptor antagonist, RP 67580 (1 and 10 mg/kg). Results indicate that escape latency increased as a function of probe height in both naive and CCI rats. Pregabalin (10 and 30 mg/kg) and morphine (5 mg/kg), but not RP 67580, decreased latency to escape in CCI rats suggesting an antinociceptive effect. In contrast, morphine (10 mg/kg) but not pregabalin (30 mg/kg) increased escape latency in naive rats suggesting a possible anxiolytic action of morphine in response to light-induced fear. No order effects following multiple test sessions were observed. We conclude that the MCS is a valid method to assess behavioral signs of affective pain in rodents.

PMID:
26915030
PMCID:
PMC4767889
DOI:
10.1371/journal.pone.0150164
[Indexed for MEDLINE]
Free PMC Article

Publication types, MeSH terms, Substances, Secondary source ID, Grant support

Publication types

MeSH terms

Substances

Secondary source ID

Grant support

Supplemental Content

Full text links

Icon for Public Library of Science Icon for PubMed Central
Loading ...
Support Center