Objective: To search for cosegregation of a change in specific blood cells with either the hypertension or the hyperactivity phenotype in spontaneously hypertensive rats (SHR), Wistar-Kyoto (WKY) rats and two new inbred strains.
Design and methods: Standard hematological procedures were used to examine erythrocytes, leukocytes and platelets in blood drawn from adult SHR, WKY rats and the two new inbred strains of rats.
Results: The hypertensive strains exhibited significant erythrocytosis, microcytosis, lymphocytosis and monocytosis relative to the normotensive strains. The hyperactive strains exhibited significant neutrophilia and increased platelet count relative to the non-hyperactive strains.
Conclusion: Not all of the differences in blood cells described originally in SHR versus WKY rats were associated with the inheritance of hypertension. The changes in the lymphocytes and in the erythrocytes should be examined as possible factors in the pathophysiology of hypertension.