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Sub-chronic Effect Of Co-administration Of Methformine And Amilodipine On Some Haematological Indices In Experimental Animal
[A CASE STUDY OF WISTAR RATS]
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2.4 Metformin and haemolytic anaemia (drug-induced hemolytic anaemia)
Metformin have related to hemolytic anaemia in some particular patients (Bashar et al., 2010). But no certain mechanism have been posulated for the Haemolysis. Some researchers believed it is due to binding of drug to RBC membrane thereby causing hemolysis, some believe it is through G6PD mechanism. Hemolysis is the destruction or removal of red blood cells from the circulation before their normal life span of 120 days (Dacie and Lewis, 2006). While haemolysis can be a lifelong asymptomatic condition, it most often presents as anaemia when erythrocytosis cannot match the pace of red cell destruction. Haemolysis also can manifest as jaundice, cholelithiasis, or isolated reticulocytosis (Dacie and Lewis, 2006). There are two mechanisms of haemolysis, (a) intravascular haemolysis which is the destruction of red blood cells in the circulation with the release of cell contents into the plasma. Mechanical trauma from a damaged endothelium, complement fixation and activation on the cell surface, and infectious agents may cause direct membrane degradation and cell destruction (Bashar et al., 2010).
The more common extravascular haemolysis is the removal and destruction of red blood cells with membrane alterations by the macrophages of the spleen and liver. Circulating blood is filtered continuously through thin walled splenic cords into the splenic sinusoids (with fenestrated basement membranes), a sponge like labyrinth of macrophages with long dendritic processes (Bashar et al., 2010). A normal 8-micron red blood cell can deform itself and pass through the 3-micron openings in the splenic cords. Red blood cells with structural alterations of the membrane surface (including antibodies) are unable to traverse this network and are phagocytosed and destroyed by macrophages (Bashar et al., 2010).
2.5 Diagnosis of anaemia
Anaemia is the most common hematologic disorder. Anaemia is best defined in relation to H&H (haemoglobin (Hb) and haematocrit (HCT) levels below the normal reference range, because a patient’s symptoms and physiologic consequences are the result of decreased oxygen-carrying capacity of the blood (Barros et al., 2010). According to World Health Organization (WHO) criteria, anaemia is diagnosed in males when Hb is <130 g/L (13 g/dL) and HCT is <0.39 (39%); and in females, when Hb is <120 g/L (12 g/dL) and HCT is <0.36 (36%).Other terms that indicate the presence of anaemia are;
Haemoglobin concentration (Hb)
Hb is an estimate of the oxygen-carrying capacity of the blood (Dacie and Lewis, 2006).
Haematocrit value or ratio (HCT)
HCT is also called packed cell volume (PCV). A measure of the relative volume occupied by RBCs in capillary or venous whole blood samples (Bashar et al., 2010). The HCT reflects, therefore, the body’s red cell mass divided by the total blood volume. The HCT is used to detect the presence or absence of anaemia and polycythemia. The HCT can be determined mechanically, by spinning the cells in a microcentrifuge, and electronically, using an automated cell counter (Dacie and Lewis, 2006). The spun microhaematocrit suffers from an inherent problem of plasma trapping and is often slightly higher (0.01–0.03 or 1–3%) than the automated haematocrit (Dacie and Lewis, 2006). This phenomenon causes an erroneously high manual HCT in samples with deformed RBCs such as sickle cells. In normal samples, the microhaematocrit and the electronic HCT should agree within ±3% (HCT units). Although the spun microhaematocrit has limitations, it is the reference method for HCT measurements. The haematocrit on Cell-Dyn hematology analyzers is a calculated parameter, expressed as percent or L/L (SI units) derived from the following equation: HCT (L/L) = RBC (1012/L) _ MCV (fL)/1000.
Mean cell volume (MCV)
This is a measure of cell volume (in fL) that is more reproducible than the RBC size information obtained from the blood film. Clinicians arbitrarily use a range of 80–100 fL as normal. MCV is very useful in determining the anaemia type, because only a few pathologies cause abnormal MCV results. In conditions of rapid blood loss or chronic disease, the MCV will be normal with a low HCT. Iron deficiency and thalassemia show a decreased MCV. Folate or vitamin B12 deficiency, alcoholism, and myelodysplastic syndrome result in an increased MCV (Dacie and Lewis, 2006).
Reticulocyte count
In most patients with haemolysis, the destruction of red cells is accompanied by an increase in the reticulocyte count. Reticulocytes are red cells that still contain RNA and are a marker of red cells that are approximately 24 hours old or less. Traditionally, reticulocytes were measured manually by staining the blood smear with vital blue and counting the percentage of cells that absorb the stain; this percentage needs to be adjusted for the haematocrit. Usually a percentage above 1.5% is considered indicative of an elevated reticulocyte count. Recently, automated complete blood count machines have taken advantage of the fact that reticulocytes will absorb certain stains; these machines can directly measure the reticulocyte count via flow cytometry, which results in an “absolute†reticulocyte count (Dacie and Lewis, 2006). The reticulocyte count obtained using this method does not have to be corrected for haematocrit, and levels of approximately 90,000/μL are considered raised. However, the reticulocyte count can also be raised in blood loss or in patients who have other causes of anaemia (e.g, iron deficiency) under treatment (Dacie and Lewis, 2006).
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ABSRACT - [ Total Page(s): 1 ]ABSTRACTMetformin, which belongs to the biguanide class, is one of the most generally used oral hypoglycemic agents. It has been used for more than 50 years and was approved by the US Food and Drug Administration (FDA) in 1994 (American Diabetes Association, 2009) whereas Amlodipine is a long acting dihydropyridine calcium channel blocker, which is used in the treatment of angina to lower the BP (Blood pressure). the aim is to know the effect of co-administration of this two drugs in Wistar rats ... Continue reading---
APPENDIX A - [ Total Page(s): 1 ]APPENDIXAPPENDIX 1: MATERIAL USED1% Ammonium oxalate10% Formalin salineAbsorbent paperAutomatic pipetteBrilliant cresyl blueCounting chamber Cyanmethaemoglobin standardDrabkin’s ReagentEDTA sample containerHematoxylin and Eosin stainKhan tubes/rackLeisfhmann stainLight microscopeMicrohaematocrit centrifugeNormal salinePasteur pipettePipette tipsRotary microtomeSpectrophotometerTimer Turk’s solution Universal sample bottle ... Continue reading---
APPENDIX B - [ Total Page(s): 1 ]APPENDIX IITable 1: haematological parameters in control, Metformine treated and Amilodipine treated Rats (Values are expressed as mean ± Standard error of means) Group A(1): control (untreated), Group B(2): co-administration of Metformin 0.00264/ml/132g and Amlodipine 0.000849/ml/132g at a single dose for 30 daysPARAMETERS GROUP A GROUP BPacked cell volume (%) 44.16±2.83 38.47±3.53Red blood cell count (x1012/L) 7 ... Continue reading---
LIST OF TABLES - [ Total Page(s): 1 ]LIST OF TABLESTable 1: Haematological parameters in control, Co-administration of Metformin and Amlodipine treated ... Continue reading---
LIST OF FIGURES - [ Total Page(s): 1 ]LIST OF FIGURESFigure 1: Shows mechanism of action of metformin Figure 2: Shows Pie chat representation of Packed cell volume of control, Co-administration of metformin and amlodipine treated Wistar Rats Figure 3: Shows Histogram representation of Hemoglobin and red blood cell count of control, Co-administration of metformin and amlodipine treated Wistar Rats Figure 4: Shows Histogram representation of red cell indicies of control, Co-administration of metformin and amlodipine t ... Continue reading---
TABLE OF CONTENTS - [ Total Page(s): 1 ]TABLE OF CONTENTTitle page Declaration Certification Dedication Acknowledgement Table of content List of table List of figures Abstract CHAPTER ONE1.0 Introduction 1.1 Background of study 1.2 Statement of Problems 1.3 Justifications 1.4 Aims 1.5 Research Objectives 1.6 Research Hypothesis 1.7 Significance of research CHAPTER TWO2.0 Literature review 2.1 Metformin 2.1.1 ... Continue reading---
CHAPTER ONE - [ Total Page(s): 2 ]CHAPTER ONE1.0 INTRODUCTION1.1 Background of the studyMetformin, which belongs to the biguanide class, is one of the most generally used oral hypoglycemic agents. It has been used for more than 50 years and was approved by the US Food and Drug Administration (FDA) in 1994 (American Diabetes Association, 2009). Currently, many clinical practice guidelines for patients with type 2 diabetes, including the American Diabetes Association (ADA), the European Association for the Study of Diabetes ... Continue reading---
CHAPTER THREE - [ Total Page(s): 4 ]From the above table,Km of rats= 6 Km of human= 37For Amlodipine, Human dose= 10mg/70kg 1kg=10/70 =0.14mg/kgAED of Amilodipine= 0.14×(6/37) =0.02mg/kgAverage weight of experimental Animal is 132g(0.132kg)If 0.02mg of Amlodipine is administered per kg.bw,(0.02×0.132)mg of Amlodipine was administered to ... Continue reading---
CHAPTER FOUR - [ Total Page(s): 6 ]CHAPTER FOUR4.0 Results4.1 Hematological parameter in control and test groups As summarized in table 1, the mean RBC counts were 7.62 ± 2.83 x1012/L for the control and 6.53 ± 0.57 x1012/L for co-administration of metformin and amlodipine fed groups respectively. Although, decrease in RBC counts was observed in the treated (co-administration of metformin and amlodipine) dose group, these were statistically significant compared to control groups (student t test P0.05) higher in the tr ... Continue reading---
CHAPTER FIVE - [ Total Page(s): 2 ]CHAPTER FIVE5.0 DiscussionMetformin (1,1-dimethylbiguanide) is the most widely used drug to treat type 2 diabetes, and is one of only two oral anti-diabetic drugs on the World Health Organization (WHO) list of essential medicines (American Diabetes Association, 2009). Amlodipine is a long acting dihydropyridine calcium channel blocker, which is used in the treatment of angina to lower the BP. Co-administration of Metformin and Amlodipine have been discovered to lead to vitamin B12 deficiency. Al ... Continue reading---
REFRENCES - [ Total Page(s): 4 ]Senol, M.G., Sonmez, G., Ozdag, F. and Saracoglu, M. (2008). Reversible myelopathy with vitamin B12 deficiency. Singapore Medical Journal. 49(11): 330-332.Srinivasan, S., Ambler, G.R., Baur, L.A., Garnett, S.P. and Tepsa, M. (2006). Randomized, controlled trial of metformin for obesity and insulin resistance in children and adolescents: improvement in body composition and fasting insulin. Journal of Clinical Endocrinology and Metabolism. 91: 2074-2080. Sterne, J. (1957). Du nouveau dans les anti ... Continue reading---
