Stereological study of the adrenal gland of calves treated with clenbuterol

Stereological methods were used to investigate the morphometric variations in the adrenal cell population of calves dosed orally with clenbuterol at a n anabolic dose of 20 mug/kg bodyweight per day for 12 weeks. In the treate d group the size of the nuclei increased with respect to the control group, and the increases were significant for the maximum linear parameters in al l the regions except the zona fasciculata. The largest increases were obser ved in the epinephrine-producing cells. The quantitative stereological data showed highly significant increases in the nuclear volume fraction, the nu clear surface density and the numerical density in the zona fasciculata of the treated group.