search
for
 About Bioline  All Journals  Testimonials  Membership  News  Donations


Malaysian Journal of Medical Sciences
School of Medical Sciences, Universiti Sains Malaysia
ISSN: 1394-195X
Vol. 20, No. 4, 2013, pp. 5-12
Bioline Code: mj13049
Full paper language: English
Document type: Review Article
Document available free of charge

Malaysian Journal of Medical Sciences, Vol. 20, No. 4, 2013, pp. 5-12

 en Four Possible Itching Pathways Related to the TRPV1 Channel, Histamine, PAR-2 and Serotonin
Nakagawa, Hiroshi & Hiura, Akio

Abstract

The following four possible pathways for itching sensation have been suggested by recent reports. 1) Histaminergic TRPV1-positive pathway: Although histamine-positive nerve fibers cannot strictly be classified as “itch specific” due to their excitation also by pure algogens (making them itch-selective), the existence of a subpopulation of nociceptors responsible for itching is strongly suggested. Moreover, the TRPV1-expressing neurons have been suggested to be the main sensors and mediators of itching. 2) Histaminergic TRPV1-negative pathway: The scratching behavior caused by itching was not different between capsaicin-pre-treated and vehicle-treated (control) mast cell-rich NC mice. This result suggests the existence of a capsaicin-insensitive (TRPV1-negative) histaminergic pathway. 3) Non-histaminergic PAR-2 pathway: Protease-activated receptor 2 (PAR-2) has been shown to play a role in the itching of atopic dermatitis (AD). The itch evoked by cowhage (a non-histaminergic pruritogen that activates PAR-2) is very similar in characteristics to the itch evoked by conditions such as AD. 4) Non-histaminergic serotonin (5-HT) pathway: 5-HT alone applied to the human skin evokes an itching sensation and has been suggested to be involved in the itching associated with pruritic diseases, such as polycythemia vera and cholestasis.

Keywords
itch; TRPV1; histamine; PAR-2; serotonin

 
© Malaysian Journal of Medical Sciences
Alternative site location: http://www.medic.usm.my/publication/mjms/

Home Faq Resources Email Bioline
© Bioline International, 1989 - 2017, Site last up-dated on 16-Oct-2017.
Site created and maintained by the Reference Center on Environmental Information, CRIA, Brazil
System hosted by the Internet Data Center of Rede Nacional de Ensino e Pesquisa, RNP, Brazil