Cadmium induces microcytosis, hypochromicity, and anisocytosis without anaemia in hypertensive rats

Background: and Aim: Dietary cadmium (Cd2+) intake is implicated in the pathogenesis of hypertension and anaemia, but there is a paucity of information on the haematological changes in hypertensive conditions. This study, therefore, aims to evaluate the effects of Cd2+ on blood pressure (BP) and haematological indices in the Sprague-Dawley rat model. Method: Three cohorts (n=10 each) of control and Cd2+-fed male Sprague-Dawley rats were selected. Cd2+-exposed rats received 2.5 or 5 mg/kg b.w. cadmium chloride via gavage thrice- weekly for eight weeks, while control animals received tap water. BP and flow were measured non-invasively from rat tails twice-weekly using a CODA machine, while weights were measured thrice-weekly. Haematological indices were assessed using the Cell-Dyn Emerald Haematology Analyzer (Abbott Diagnostics, IL, USA). Data were reported as mean ± SEM, and statistically analyzed using One-Way Analysis of Variance. Bonferroni post hoc test was used for multiple comparisons. Results: Cd2+-exposure induced hypertension by significantly (p<0.05) elevating systolic, diastolic, and mean arterial BPs, pulse pressure, and heart rate (HR), and increased (p<0.05) blood flow. Mean cell volume (MCV) and haemoglobin (MCH) were significantly (p<0.05) reduced, and red cell distribution width (RDW) significantly (p<0.01) increased by exposure to 5 mg/kg b.w. Cd2+. Haemoglobin concentration (MCHC), haematocrit, haemoglobin, red blood cell, platelet, mean platelet volume, and white blood cell counts were unaffected by Cd2+-exposure. Conclusion: Cd2+ induced hypertension, hypochromicity, and anisocytosis without anaemia, which may be precursor to microcytic anaemia and coronary artery disease. This study is important in Cd2+-exposed environments and warrants further investigations. Keywords: Cadmium; Hypertension; Microcytosis; Hypochromic anaemia; Anisocytosis