EFFECTS OF CASTRATION AND TESTOSTERONE ON FEL-D-I PRODUCTION BY SEBACEOUS GLANDS OF MALE CATS .2. MORPHOMETRIC ASSESSMENT

A morphometric study of cat sebaceous glands was performed to evaluate the effects of castration and testosterone treatments. Skin biopsies were taken in six cats before castration, after castration and after t he testosterone injections administered after castration (total number of biopsies: 18). Ninety 8 mu m thick sections of each biopsy were as sessed for image analysis processing (SAMBA 2005, ALCATEL TITN). The v ariations in glands and cells size were evaluated on digitized microsc opic images by morphometric parameters included in;the SAMBA software package. An original software was developed for the analysis of the sp acial gland structure. The best morphometric parameters were selected in a first step of the study, and included the nuclear surface (NS), t he cell surface (CS) and the nuclear/cellular surface ratio (N/C). The se three parameters were then compared in each group of samples for th e six cats. It was shown that after castration the N/C (21%) significa ntly increased compared with prior to castration (12.6%). This 59.8% i ncrease was mainly due to cell cytoplasm shrinking reflecting a decrea se of the cell activity. The testosterone administered after castratio n produced a reverse effect with a N/C ratio back to normal (11.4%) an d a significant cell cytoplasm and gland enlargement as shown by the t hree dimension constructions. This morphometric data correlated with t he measurement of sebum and Fel d I productions. The negative effects of castration and the positive effects of testosterone on the sebaceou s cells and glands volume favour the hypothesis that cat sebaceous cel ls are subject to hormonal control this is also likely to apply to the Fel d I production.