The effect of cold and haemorrhagic stress on reticulocytes in male albino Wistar rats

Abstract

Background: In this study, the effect of cold and haemorrhagic stressors in male albino Wistar rats will be investigated. Methods: Cold stress was induced by placing the animals in thermostatic chamber containing ice cold water (0-10oC) and well aerated. Rats were allowed to stay for 5, 10, 15 and 20 minutes before they were bled from the tail vein at 2, 4, 6, 8 and 24 hours for reticulocyte counts. For the haemorrhagic stress, 30% of blood was withdrawn from the vein after which reticulocytes were counted at 2, 4, 6, 8 and 24 hours. Results: Cold and haemorrhagic stress caused increased reticulocyte counts in male albino Wistar rats. The controls were not subjected to any condition. In cold stress, the maximum percentage reticulocyte count was (at zero hour) 6.21 + 0.21% while the control was 1.02 + 0.12%. In the case of the haemorrhagic stressor, the percentage reticulocyte was seen to peak at the 6th hour (6.19 + 0.12%) and subsequently decrease to 2.59 + 0.02%. The probable causes of this rise in reticulocytes are discussed. Conclusion: In cold and haemorrhagic stress, reticulocyte count peaked at 2 and 6 hours respectively, depicting when maximum erythropoietic activity was reached in blood forming organs. Keywords: vPort Harcourt Medical Journal Vol. 3 (1) 2008: pp. 72-76