1Phérosynthèse, Le Rieu Neuf , 84490 Saint Saturnin d'Apt, France.
2UPRES 2050, Service de Pneumologie, Hôpital Sainte Marguerite, 13005 Marseille, France.
Recent studies have confirmed that Fel d 1 concentration on the cat fur is higher in
males than in females. The Fel d 1 production is under hormonal control in males and
decreases after castration. In contrast, castration in females does not affect Fel d 1. The
close association of Fel d 1 with anal sacs and sebaceous glands, and the structural similarity
of chain 1 of Fel d 1 with steroid-binding proteins suggest a possible role for Fel d 1 as a
pheromone-binding protein.
This study aimed at measuring Fel d 1 levels in two different anatomical areas, known as
producer (face) or not producer (thorax) of pheromones. Ten intact male cats were clipped
under general anesthesia at 2 areas, the fur was collected and the skin washed. Fel d 1
concentrations were calculated in U/g fur and mU/cm2 using Elisa method with monoclonal
antibodies. The mean of Fel d 1 on fur is significantly higher in the facial area (14.0 + 6.8 U/g)
than in the thoracic area (5.1 + 3.1 U/g). The same trend is shown in skin washings: levels
are significantly higher in the facial area (29.1 + 31.6 mU/cm2) than in the
thoracic area (10.7 + 9.6 mU/cm2). Furthermore the Fel d 1 synthesis by the
skin of the facial area was as a mean 10 times higher than synthesis by the skin of the
thoracic area.
These results reinforce the possibility for Fel d 1 being a carrier protein for social
communication molecules.