Actions of Isotretinoin and Etretinate on the Pilosebaceous Unit

The study investigated the effects of isotretinoin and etretinate on the sebaceous glands in male and female hamsters. Isotretinoin, when administered subcutaneously to male hamsters, caused significant reduction in the sebaceous glands of the flank organ without affecting other androgen-dependent structures. In androgen-stimulated female hamsters, isotretinoin prevented the androgen-induced growth of sebaceous glands but did not affect the formation of large pigmented hairs and dermal pigment cells. Etretinate, however, did not inhibit sebaceous gland growth at comparable dosages. The findings suggested that the hamster flank organ could be a useful model for evaluating the sebaceous gland inhibitory activity of retinoids, potentially predicting their therapeutic efficacy in treating acne.