Objective: The purpose of this study was to investigate the acute effect of ethanol (4g/kg, IP) on granulopoiesis at two phases of the rat estrous cycle, proestrus and diestrus Day 1.
Method: The following parameters were estimated: in peripheral blood, the ethanol concentration, progesterone and estradiol levels, the total number of WBC and differential count: in the bone marrow, the total number of nucleated cells, the number of granulocyte-macrophage committed stem cells (CFU-GM) and differential count at various time points (5, 3, 6 and 20 hours) after treatment. The experiments were conducted twice and 4 to 7 rats were used per groups for each time point.
Results: The results indicated that a single dose of ethanol significantly increased the number of granulocytes and decreased the number of lymphocytes in peripheral blood. These changes were observed earlier at the proestrus compared to the diestrus Day 1, and were consistent with faster ethanol disappearance from blood during the proestrus. Additionally, the ethanol treatment induced a significant increase in progesterone levels at both phases. This effect was prolonged at the diestrus Day 1 and thus was also associated with differences in ethanol metabolism. In the bone marrow, the total number of nucleated cells and morphologically recognizable hematopoietic cells were not affected by ethanol treatment at any of the observed time points. However, at both phases of the estrous cycle ethanol treatment induced an increase in the number of CFU-GM derived colonies 20 hours after administration.
Conclusions: The data obtained suggest active involvement of the granulocytic cell line in response to acute ethanol administration which is modulated by the current hormone status of the treated animals.