Effects of methylprednisolone pulses on renal function of guinea pigs.

Methylprednisolone produced a dose dependant significant increase in glomerular filtration rate, a significant decrease in sodium excretion, and a significant increase in urinary alkaline phosphatase activity in guinea pigs. The renal histology in groups with 4, 5 and 6 doses revealed mild degenerative changes in the tubular epithelial cells. The results suggest the beneficial effects of methylprednisolone pulse therapy on renal function mainly by increasing glomerular filtration rate with only minimal side effects.