RT Journal Article
SR Electronic
T1 Topical Surfactant-Induced Pruritus: Involvement of Histamine Released from Epidermal Keratinocytes
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 459
OP 466
DO 10.1124/jpet.112.200063
VO 344
IS 2
A1 Yoshihiro Inami
A1 Tsugunobu Andoh
A1 Atsushi Sasaki
A1 Yasushi Kuraishi
YR 2013
UL http://jpet.aspetjournals.org/content/344/2/459.abstract
AB Surfactants, an important component of cleansers, often cause itch in humans. Topical application of sodium laurate and N-lauroylsarcosine sodium salt to the skin of mice immediately (for 1–1.5 hours) increased scratching, and the former increased scratching again between 2 and 3 hours after application. Thus, we examined the mechanisms of sodium laurate–induced delayed scratching. Sodium laurate (0.1%–10%) increased delayed scratching and skin surface pH in a concentration-dependent manner. N-lauroylsarcosine sodium salt had no effect on these parameters, and sodium hydroxide solution did not increase delayed scratching. Sodium laurate–induced delayed scratching was markedly inhibited by the H1 histamine receptor antagonist terfenadine, but it was not affected by mast cell deficiency. Sodium laurate application had no effect on the number of total and degranulated mast cells, and did not induce plasma extravasation or the infiltration of inflammatory cells in the skin. Sodium laurate application increased the histamine content of the epidermis, but not that of the dermis, in normal and mast cell–deficient mice. Sodium laurate application increased the ratio of 53-kDa l-histidine decarboxylase (HDC, a key enzyme for histamine production) to 74-kDa HDC in the mouse epidermis and in a human keratinocyte culture. Sodium laurate increased histamine in the human keratinocyte culture, without affecting cell viability. The present results suggest that sodium laurate induced delayed scratching at an alkaline pH through the increased production of histamine in keratinocytes, which may be due to enhanced processing of 74-kDa to 53-kDa HDC.