EFFECTS OF TESTOSTERONE AND CORTISOL ON THE RENAL MORPHOLOGY OF MALE ANTECHINUS-STUARTII (MARSUPIALIA)

The life cycle of the marsupial Antechinus stuartii includes postmatin g mortality of all males. A previous study found that renal morphology changes during the yearly cycle when endogenous concentrations of tes tosterone and cortisol are elevated in males. The present study determ ined whether administration of testosterone only cortisol only, or tes tosterone plus cortisol affects renal structure in males at a time of year when endogenous hormones are low (May). Saline administration was used as the control. Gross morphometrics of the kidney did not show s ignificant differences between groups. However, some pathological chan ges were observed in distal tubules and collecting ducts from cortisol -treated groups, and in the glomeruli of testosterone-treated males. H ypertrophy of the proximal tubules, distal straight tubules, and the c ells of the cortical collecting duct occurred with the administration of testosterone. Distension of the distal convoluted tubules, cortical collecting ducts, and outer medullary collecting ducts occurred with the administration of cortisol, and there was some interaction with te stosterone. Glomerular volumes increased with cortisol administration, although cortisol interacted with testosterone in the superficial glo meruli. Many of these changes mimicked those seen in the seasonal stud y with the kidneys of the testosterone plus cortisol group closely res embling those of males in August, just prior to male mortality. The pr esent study demonstrates that testosterone administration causes hyper trophy of renal tissue, whereas cortisol administration can cause tubu lar disruption in male A. stuartii. (C) 1997 Academic Press.