|
|
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
BEHAVIORAL PHARMACOLOGY
Department of Applied Pharmacology, Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Toyama, Japan (H.N.); and Section of Neurobiology, Physiology, and Behavior, University of California, Davis, California (E.C.)
We investigated the role of serotonin (5-hydroxytryptamine;
5-HT)2 and 5-HT3 receptor subtypes in acute
itch-associated scratching behavior as well as in an allergic pruritus model
in rats. Intradermal 5-HT evoked hind limb scratching directed toward the
injection site in naïve rats. Scratching behavior was significantly
reduced by pretreatment with the 5-HT2 receptor antagonist
ketanserin. Intradermal injection of
-methylserotonin, a
5-HT2 receptor agonist, also elicited scratching behavior in a
dose-dependent manner, indicating that acute 5-HT-induced scratching is
mediated via peripheral 5-HT2 receptors. To produce a model of
allergic pruritus, skin was sensitized by topical application of 5%
dinitrofluorobenzene (DNFB). One month later, repeated challenge of the skin
with 0.2% DNFB at weekly intervals elicited scratching as part of the
immediate allergic response. Scratching was not affected by ketanserin or by
the 5-HT3 receptor antagonist ondansetron, indicating that neither
5-HT2 nor 5-HT3 receptors is involved in itch-associated
scratching behavior caused by allergic skin dermatitis in rats.
Address correspondence to: Dr. E. Carstens, Section of Neurobiology, Physiology and Behavior, University of California-Davis, 1 Shields Ave., Davis, CA 95616. E-mail address: eecarstens{at}ucdavis.edu
This article has been cited by other articles:
![]() |
T. Akiyama, A. W. Merrill, K. Zanotto, M. I. Carstens, and E. Carstens Scratching Behavior and Fos Expression in Superficial Dorsal Horn Elicited by Protease-Activated Receptor Agonists and Other Itch Mediators in Mice J. Pharmacol. Exp. Ther., June 1, 2009; 329(3): 945 - 951. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Akiyama, A. W. Merrill, M. I. Carstens, and E. Carstens Activation of Superficial Dorsal Horn Neurons in the Mouse by a PAR-2 Agonist and 5-HT: Potential Role in Itch J. Neurosci., May 20, 2009; 29(20): 6691 - 6699. [Abstract] [Full Text] [PDF] |
||||