Characterization of Nociceptive Behaviors Induced by Formalin in the Glabrous and Hairy Skin of Rats.

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Glabrous skin and hairy skin are innervated by different types of noxious fibers. However, the different nociceptive behaviors induced by formalin, a commonly used model of acute inflammatory pain, have not yet been systematically examined in the glabrous and hairy skin.

Related collections

Most cited references 29

Record: found
Abstract: found
Article: not found

The formalin test in mice: dissociation between inflammatory and non-inflammatory pain.

Michael Hole, S Hunskaar (1987)

The formalin test in mice is a valid and reliable model of nociception and is sensitive for various classes of analgesic drugs. The noxious stimulus is an injection of dilute formalin (1% in saline) under the skin of the dorsal surface of the right hindpaw. The response is the amount of time the animals spend licking the injected paw. Two distinct periods of high licking activity can be identified, an early phase lasting the first 5 min and a late phase lasting from 20 to 30 min after the injection of formalin. In order to elucidate the involvement of inflammatory processes in the two phases, we tested different classes of drugs in the two phases independently. Morphine, codeine, nefopam, and orphenadrine, as examples of centrally acting analgesics, were antinociceptive in both phases. In contrast, the non-steroid anti-inflammatory drugs indomethacin and naproxen and the steroids dexamethasone and hydrocortisone inhibited only the late phase, while acetylsalicylic acid (ASA) and paracetamol were antinociceptive in both phases. The results demonstrate that the two phases in the formalin test may have different nociceptive mechanisms. It is suggested that the early phase is due to a direct effect on nociceptors and that prostaglandins do not play an important role during this phase. The late phase seems to be an inflammatory response with inflammatory pain that can be inhibited by anti-inflammatory drugs. ASA and paracetamol seem to have actions independent of their inhibition of prostaglandin synthesis and they also have effects on non-inflammatory pain.

0 comments Cited 207 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

The formalin test: A quantitative study of the analgesic effects of morphine, meperidine, and brain stem stimulation in rats and cats

David Dubuisson, Stephen G. Dennis (1977)

A method for assessing pain and analgesia in rats and cats is described. The procedure involves subcutaneous injection of dilute formalin into the forepaw, after which the animal's responses are rated according to objective behavioral criteria. The formalin test is a statistically valid technique which has two advantages over other pain tests: (1) little or no restraint is necessary, permitting unhindered observation of the complete range of behavioral responses; and (2) the pain stimulus is continuous rather than transient, thus bearing greater resemblance to most clinical pain. The analgesic effects of morphine, meperidine, and stimulation of the periaqueductal grey matter are evaluated using this test.

0 comments Cited 171 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Evidence for a central component of post-injury pain hypersensitivity.

C J Woolf (2015)

Noxious skin stimuli which are sufficiently intense to produce tissue injury, characteristically generate prolonged post-stimulus sensory disturbances that include continuing pain, an increased sensitivity to noxious stimuli and pain following innocuous stimuli. This could result from either a reduction in the thresholds of skin nociceptors (sensitization) or an increase in the excitability of the central nervous system so that normal inputs now evoke exaggerated responses. Because sensitization of peripheral receptors occurs following injury, a peripheral mechanism is widely held to be responsible for post-injury hypersensitivity. To investigate this I have now developed an animal model where changes occur in the threshold and responsiveness of the flexor reflex following peripheral injury that are analogous to the sensory changes found in man. Electrophysiological analysis of the injury-induced increase in excitability of the flexion reflex shows that it in part arises from changes in the activity of the spinal cord. The long-term consequences of noxious stimuli result, therefore, from central as well as from peripheral changes.

0 comments Cited 117 times – based on 0 reviews      Review now

Bookmark

All references

Author and article information

Journal

Journal ID (iso-abbrev): Basic Clin Neurosci

Title: Basic and clinical neuroscience

Publisher: OMICS Publishing Group

ISSN: 2008-126X

ISSN (Print): 2008-126X

Publication date (Electronic): Jan 2017

Volume: 8

Issue: 1

Affiliations

[1 ] Department of Nursing, Faculty of Nursing and Midwifery, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran.

[2 ] Department of Information Physiology, National Institute for Physiological Sciences, Okazaki, Japan.

[3 ] Department of Medical Basic Sciences and Neuroscience Research Center, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran.

[4 ] School of Life Science, University for Advanced studies (SOKENDAI), Okazaki, Japan.