083 Expression of Angiotensin Type 1 Receptor in the Hair Follicle and the Hair Follicle associated Tumors.

Hikaru Takeda, Shigeo Kondo. Department of Dermatology, Yamagata University School of Medicine, Yamagata, Japan.

Angiotensin receptors are the specific receptors of angiotensin II of the rennin-angiotensin system. The existence and distribution of the receptors in the hair follicle have not been clarified. We immunohistochemically studied the expression of the receptors in the human hair follicle using normal scalp skin from a 24-year-old Japanese man. The experiments demonstrated the expression of angiotensin type 1 receptor (AT1) in the inner root sheath and the outer root sheath except for the basal layer. The expression pattern suggests the role of AT1 in association with keratinization. Based on the results, we studied the expression of AT1 in the hair follicle-associated tumors such as epidermal cyst and basal cell carcinoma. The cases were selected from the files of the Yamagata University Hospital, Japan between 1995-1999. The results revealed the distinct staining patterns of these tumors, respectively. These observations suggest that studying AT1 expression may be useful in understanding the pathophysiology of the hair follicle and the associated tumors.