Hematocrit and hemoglobin values are negatively correlated with insulin resistance in spontaneous hypertension

It has been recently reported that increased hematocrit and hemoglobin valu es often accompany insulin resistance and compensatory hyperinsulinemia in humans. In the current study, we analyzed the relationship between hematocr it/hemoglobin on the one hand and insulin resistance, dyslipidemia, and hyp ertension on the other hand in HXE/BXH recombinant inbred (RI) strains deri ved from the spontaneously hypertensive rat (SHR) and the Brown Norway (BN) rat. The SHR progenitor strain had a significantly increased hematocrit va lues and it,vas also hypertensive and insulin-resistant when compared with the BN progenitor. The distribution of hematocrit and hemoglobin values amo ng RI strains was continuous, suggesting a polygenic mode of inheritance. A nalysis of RI strains revealed that hemoglobin was negatively correlated wi th insulin and insulin/glucose ratio, and that hematocrit was negatively co rrelated with insulin-stimulated glucose uptake in isolated adipocytes, The re was no relationship between hematological parameters and blood pressure or lipid phenotypes in RI strains. The findings of the current study sugges t that hematocrit and hemoglobin values might be added to the clustering va riables related to the insulin resistance syndrome in the SHR strain.