Renal and cardiac effects of the PDE9 inhibitor BAY 73-6691 in 5/6 nephrectomized rats.

We examined the effects of the PDE9 inhibitor BAY 73-6691 on the kidney and heart for the first time in a 5/6 nephrectomy animal model using BAY 73-6691 dosages known to be effective in other rat disease models. We did not observe any relevant effects of the PDE9 inhibitor BAY 73-6691 on renal function, renal histology, and renal disease-related pathways and gene expression in 5/6 nephrectomy rats. In addition, the effects of the PDE9 inhibitor BAY 73-6691 on the heart of 5/6 nephrectomy rats were mild. Except for cardiomyocyte size, BAY 73-6691 had no effect on other cardiac histological parameters, cardiac function, and disease-related genes and pathways.