Effects of castration and testosterone on Fel d I production by sebaceous glands of male cats: II—morphometric assessment

Abstract

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 the testosterone injections administered after castration (total number of biopsies: 18). Ninety 811m thick sections of each biopsy were assessed for image analysis processing (SAM BA 2005, ALCATEL TITN). The variations in glands and cells size were evaluated on digitized microscopic images by morphometric parameters included in the SAMBA software package. An original software was developed for the analysis of the spacial gland structure. The best morphometric parameters were selected in a first step of the study, and included the nuclear surface (NS), the cell surface (CS) and the nuclear/cellular surface ratio (N/C). These three parameters were then compared in each group of samples for the six cats. It was shown that after castration the N/C (21%) significantly increased compared with prior to castration (12'6%), This 59·8% increase was mainly due to cell cytoplasm shrinking reflecting a decrease of the cell activity. The testosterone administered after castration produced a reverse effect with a N/C ratio back to normal (11-4%) and a significant cell cytoplasm and gland enlargement as shown by the three dimension constructions. This morphometric data correlated with the measurement of sebum and Feld I productions. The negative effects of castration and the positive effects of testosterone on the sebaceous cells and glands volume favour the hypothesis that cat sebaceous cells are subject to hormonal control this is also likely to apply to the Feld I production.

Fel d I levels in cat anal glands

“…Production of Eel J I by skin and by sebaceous glands in the latter was confirmed by studies done by our group [5,6]. Furthermore, it was recently demonstrated that Eel d I concentrations on the skin are under hormonal control in parallel with the sebaceous cells and glands volume [7]. Cats have tubular anal glands which have been described in histochemical study as structures of apocrine and holocrine glands with a large amount of sebaceous glands and secretion of sebum, proteins, and lipids [10].…”

EAACI Molecular Allergology User's Guide

“…Fel d 1, the major cat allergen, is an uteroglobin expressed in salivary glands and skin. The production of Fel d 1 is related to sexual hormones . Three allergens are known to have surfactant properties, Equ c 1, Equ c 4, and Fel d 8.…”

Immunization of cats to induce neutralizing antibodies against Fel d 1, the major feline allergen in human subjects

“…[25][26][27][28][29] Male cats exhibit higher levels of the protein and, on castration, reach similar levels compared with female cats. 30 Although some function in pheromone binding 31 and pelt conditioning has been suggested, the biological function of Fel d 1 remains uncertain. A vaccine targeting Fel d 1 in cats will affect the allergic response at the first possible point of intervention by inducing Fel d 1-specific antibodies in the animal.…”