The influence of mouse Ped gene expression on postnatal development.

The Ped (preimplantation embryo development) gene, whose product is Qa-2 protein, is correlated with a faster rate of preimplantation development (Ped fast phenotype) in mice that express Qa-2 protein compared with mice with an absence of Qa-2 protein (Ped slow phenotype). In the current study, we have used two congenic mouse strains differentially expressing the Ped gene, strain B6.K1 (Ped slow; Qa-2 negative) and strain B6.K2 (Ped fast; Qa-2 positive), to investigate the effects of Ped gene expression on postnatal growth profiles, systolic blood pressure and adult organ allometry. At birth, B6.K1 mice were moderately lighter than B6.K2 mice. B6.K1 mice became heavier during postnatal life (P < 0.05) and had elevated systolic blood pressure at 21 weeks of age when compared with B6.K2 mice (P = 0.006). B6.K1 mice also demonstrated elevated serum angiotensin-converting enzyme (ACE) activity, a known regulator of blood pressure (P = 0.037). Altered organ:body weight ratios were also observed, with the B6.K1 females having a higher ratio for lungs than B6. K2 females (P = 0.014). These data provide evidence of an association between the rate of preimplantation embryo development, postnatal growth and later cardiovascular function.