Histology of the interrenal gland of Rhinella arenarum (Amphibia, Anura)

REGUEIRA ELEONORA; SASSONE ALINA; VOLONTERI CLARA; SCAIA MARIA FLORENCIA; CEBALLOS NORA RAQUEL

Congreso; II Reunión Conjunta de las Sociedades de Biología de la República Argentina; 2011

Interrenal gland of anurans is composed of different cell types: steroidogenics, which synthesize aldosterone and corticosterone; chromaffins, which produce catecholamines; ganglionars, sympathetic neurons; and in some species Stilling cells, of uncertain function. The aim of this work is to analyze the localization of these cell types on the interrenal gland of the male toad R. arenarum and its antero-posterior variations. Serial cross and parasagittal sections were stained with hematoxilin-eosin, Masson´s trichrom and PAS. Steroidogenic and chromaffin cells were identified by immunohistochemistry with antibodies against the 3beta-hydroxysteroid dehydrogenase/ isomerase and tyrosine hydroxylase, respectively. Two steroidogenic cell types were identified: acidophilic vacuolated cells and basophilic highly immunolabeled granular cells. Both cell types are organized in cords. Basophilic cells localize in large central groups that decrease their size in the posterior region. Chromaffin cells are found isolated or in small groups near blood vessels, scattered throughout the interrenal. Ganglionar cells and nerve fibers are found innervating steroidogenic cells. PAS positive cells surrounded by steroidogenic cells could correspond to Stilling cells. In conclusion, two steroidogenic cell types of unknown functionality were found in the interrenal of R. arenarum and their proportion varies throughout the antero-posterior axis.