EFFECT OF AMPICILLIN, ERYTHROMYCIN, TETRACYCLINE AND PENICILLIN ON Escherichia coli ISOLATED FROM SOIL

CHAPTER ONE

1.1       INTRODUCTION

Hypertension also known as high blood pressure or arterial hypertension, is a chronic medical condition in which the blood pressure in the arteries is elevated (James et al, 2013). Blood pressure is expressed by two measurements, the systolic and diastolic, pressure, which are the maximum and minimum pressures respectively, in the arteries system. The systolic pressure occurs when the left ventricle is most contracted; the diastolic pressure occurs when the left ventricle is most relaxed prior to the next contraction (Chobanian et al, 2003).normal blood pressure at rest is within the range of 100 – 140mmHg systolic and 60 – 90mmHg diastolic. Hypertension is present if the blood pressure is persistently at or above 140/90mmHg for most adults; different criteria apply to children.

Hypertension usually does not cause symptoms initially, but sustained hypertension over time is a major risk factor for hypertensive heart disease, coronary arteries disease, stroke, peripheral artery disease, and chronic kidney disease (Carretero and Oparil, 2000). Hypertension is a major health problem, especially because it has no symptoms. Many people have hypertension without knowing it. There are at least 970 million people worldwide who have elevated blood preasure (hypertension). In Nigeria, 50 million people have hypertension, about 640 million people have hypertension in West Africa and about 280 million people have hypertension in Africa (Chobanion et al, 2003). Hypertension is more common in men than women and in people over the age of 65 than in younger persons. More than half of all Nigerians over the age of 65 have hypertension. Hypertension is serious because people with the condition have a higher risk for heart disease and other medical problems than people with normal pressure. Serious complications can be avoided by getting regular blood pressure checks and treating hypertension as soon as it is diagnosed (Mancia et al, 2007).

1.2       CAUSES OF HYPERTENSION

There is often no clear cause of high blood pressure but the following can be considered as risk factors;

1. Over weight
2. Family history of high blood pressure
3. Smoking
4. High salt diet
5. Low intake of fruits and vegetables
6. Lack of regular exercise
7. High intake of coffee (or other caffeine based drinks)
8. High intake of alcohol
9. Age over 65
10. Kidney disorder
11. Stress

Stressful situations can make blood pressure go up. When the stress goes away, blood pressure usually returns to normal (Fisher and Williams, 2005). These temporally increase in blood pressure is not considered hypertension. A diagnosis of hypertension is made only when a person has multiple high blood pressures reading s over a period of time. A 2010 report found that the rise in incidence of high blood pressure among children is most likely due to an increase in the number of overweight and obese children and adolescent (Chiolero et al, 2013).

1.3       USES OF PLANT EXTRACT TO TREAT HYPERTENSION

Researchers have identified local herbs and spices that have been successfully used to treat hypertension without the side effect associated with conventional drugs. Several studies have shown that moderate elevation of arterial blood pressure (BP) or rather hypertension leads to shortened life expectance. (Gbolade A. 2012). However, a recent review of natural herbs used in the treatment of hypertension has provided an introduction of the natural occurring medicinal plant that have so far been scientifically studied and reported to have hypotensive or anti-hypertensive effect. Plants having hypotensive / anti-hypertensive potential herbal remedies include parkiabiglobosa among others. This study as therefore designed to investigate the effects of P. biglobosa leaf extract on serum electrolyte (sodium, potassium, calcium) in adrenalin induced hypertensive rats.