Dorsal skin responses to topical application with hydrogen peroxide in Mini and Wistar rats.
Mini rats (Jcl: WistarTGN(ARGHGEN) 1Nts) (MRs) are Wistar rat (WR)-derived transgenic rats in which the expression of growth hormone (GH) gene is suppressed under the presence of antisense RNA transgene. In order to evaluate the effects of GH-deficiency on the acute injury by external stimuli, the dorsal skin responses to a single topical application with 20% hydrogen peroxide (HPO), one of the environmental oxidative stressors, were histologically compared between male MRs and WRs of 8 weeks old, whose hair cycle was under the telogen phase. As a result, formation of granulation tissues, reepithelialization and regrowth of hair follicles were delayed in MRs compared with WRs. While hair follicles of MRs of this age are under a long-lasting telogen phase after their 2nd cycle, a new hair cycle started not only in the HPO-applied area but also in the solvent-applied area with a little time lag. These findings suggest that GH-deficiency may influence the skin responses to the external chemical stimuli.
Umeda-Ikawa
Aya
A
Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan. akunio@mail.ecc.u-tokyo.ac.jp
Ishii
Yoshiyuki
Y
Suzuki
Kazuhiko
K
Uetsuka
Koji
K
Nakayama
Hjroyuki
H
Doi
Kunio
K
D000287:Administration, Topical; D000818:Animals; D013006:Growth Hormone / Q000172:deficiency*; D006861:Hydrogen Peroxide / Q000633:toxicity*; D008297:Male; D009336:Necrosis; D051381:Rats; D011919:Rats, Inbred Strains; D017208:Rats, Wistar; D012867:Skin / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology
D013006:Growth Hormone; D006861:Hydrogen Peroxide