THE EFFECTS OF TESTOSTERONE AND ESTRADIOL ON MAST-CELL NUMBER IN THE HARDERIAN-GLAND OF THE FROG, RANA-ESCULENTA

The Harderian gland (HG) of the frog Rana esculenta contains mast cell s in the interstitial tissue. The mast cell number (MCN) is influenced by sex hormones. Gonadectomy in both sexes provoked a decrease in MCN in January, while no effect was observed in September. Sex hormone-re placement therapy gave different results; estradiol treatment in castr ated males and females always increased MCN, while testosterone did no t. Acute estradiol treatment provoked an increase in MCN on days 2 and 4 of treatment and the morphology of the glandular compartment appear ed normal. On days 8, 10 and 12 of treatment the MCN drastically decre ased. The majority of glandular acini appeared strongly disorganized a nd the interstitial tissue became hypertrophic in concomitance with an increased vascularization. Our results suggest that estradiol acts by stimulating mast cells and acute estradiol treatment provokes prolife ration of interstitial connective tissue together with glandular cells damage.