e at position 204. hAQP2, human AQP2; mAQP1, mouse AQP1; mAQP2, mouse AQP2; rAQP2, rat AQP2; xAQP2, Xenopus AQP2. (C) Urine production (ml) and water consumption (ml) of 58 F2 mice over a 24-h period (both sexes, aged 10–22 wk). Mutant mice (black squares) exhibit overt polyuria and polydipsia compared to littermate wild-type (white triangles) and heterozygous (grey circles) mice. (D) Urine osmolality and concentrating ability in Aqp2 mutant and their littermates (10–22 wk, both sexes), before (white bars) and after (black bars) dDAVP treatment. Wild type (WT; n = 12); heterozygote (Het; n = 20); mutant (Mut; n = 9). Data represent averages ± sta