Development of Adrenal Glands from the Embryonic Phase to Puberty in Spix’s Yellow-toothed Cavies (Galea spixii, Wagler, 1831)

Abstract

ABSTRACT Several authors have underscored the importance of establishing parameters in morphological development by gender comparison to establish clinical and pre-clinical assays through the use of experimental models. Current research compares the morphometry of right and left adrenal glands of males and females and describes differentiation of the cortex and medulla tissue during the embryonic, pre-puberty and puberty phases in Spix´s yellow-toothed cavies. Embryos aged 22 (22D), 25 (25D), 30 (30D), 40 (44D) and >50 (50D) days of gestation and neonates aged 15 (15DPN) (DPN= Days postnatal), 30 (30DPN) and 90 (90DPN) days after birth were analyzed. Comparisons included morphometric and histological analysis in all periods described. When compared the right and left adrenal glands, results show that the length and width have statistical differences (p<0.05). Statistical difference between right and left glans for weight occurred only after 30D in males and after 50D in females. When compared male and females, no statistical difference in the right and left glands was extant. In the case of tissue differences, the glomerular zone is the first to emerge after 22D, followed by the fasciculate zone after 25D and by the reticular zone during the post-natal period. Medullar tissue was spread between the cortical tissue at the onset of development, establishing itself at the center of the organ since the end of pregnancy (>50D) up to puberty. Considering tissue differentiation, there was no difference between the adrenal glands of male and female cavies or between the right and left adrenal glands.