PDE1A and cystic kidney disease: To determine whether it could induce the development of renal cystic disease in Pde1a mutant mice, desmopressin (DDAVP, 30 ng/100 g BW/hr subcutaneously) or saline was administered to Pde1aInsA homozygous and wild-type mice (5 male and 5 female mice per genotype and treatment) between 4 and 16 weeks of age.