The rabbit ear model as an acnegenicity test. 2. Effect of coal tar on follicle and sebaceous gland epithelium tumor induction
Zimmermann, R.
Dermatologische Monatschrift 175(11): 691-698
1989
ISSN/ISBN: 0011-9083 PMID: 2612710 Document Number: 334753
Tar produced from hard coal was found to be acanthogenic to the interfollicular epiderm of rabbit ear skin and comedogenic to follicular epithelium in short-term (two weeks) and long-term (12 weeks) tests. Histological and autoradiographic experiments revealed a hyperproliferative effect in all cases in long-term tests. This contrasts with the atrophying effects reported by other authors. Tar application reduced the sebaceous gland area per follicle. Benignant epidermal tumours consisting of papillomas with a striking degree of sebaceous gland proliferation appeared on the rabbit ear skin after 8 weeks at the earliest.