Genetic linkage of the sarco(endo)plasmic reticulum Ca²⁺-dependent ATPase II gene to intracellular Ca²⁺ concentration in the spontaneously hypertensive rat

A cosegregation analysis of sarco(endo)plasmic reticulum Ca²⁺-dependent ATPase (SERCA) II genotype, systolic blood pressure and platelet intracellular Ca²⁺ concentration was performed to dissect polygenic hypertensive traits in spontaneously hypertensive rats. Backcross analysis between spontaneously hypertensive hypertensive rats and normotensive Donryu rats demonstrated the existence of an inferred single major gene locus (ht). Thrombin-stimulated intraplatelet Ca²⁺ concentration was significantly higher in the SERCA II homozygotes than in the heterozygotes. The SERCA II genotype did not cosegregate with the blood pressure level. The SERCA II gene was assigned to rat chromosome 12. These results suggest that the SERCA II gene on rat chromosome 12 contributes to increased thrombin-stimulated intraplatelet Ca²⁺ concentration and that the SERCA II gene is not identical to ht.