CHAPTER ONE

INTRODUCTION

1.1     BACKGROUND OF STUDY

Plants have been considered as sources of medicinal agents, as it offers natural products useful for human health. Since the existence of human life on the planet earth, plants have been the source of food, clothing, shelter, fiber, fuel and medicine. Since time immemorial plants are the principle raw materials of traditional medicinal system that has been practiced and continue to provide mankind with novel therapies (Cragg and Newmann, 2005). Rauwolfia vomitoria , is a plant specie that of the genus Rauvolfia. It is also called the “poison devils pepper”. Rauwolfia vomitoria  contains a large number of indole alkaloids, the root bark contains reserpiline as a major component, followed by reserpine, reserpinine and ajmaline. Root products of Rauwolfia vomitoria  have been found to be potent in treatment hypertension, as a sedative to calm epilepsy and psychotic or mental illness. They are also used to wash Children with Colic or fever as well as for skin problems such as rash, pimples, etc. (Schmelzer, 2007).

          Sex hormones are natural substances produced by the body that helps relay messages between cells and organs and affect development of sexual organs and other secondary sexual characteristics. Estrogen and progesterone are the two main female sex hormones. Although testosterone is considered as a male hormones females also produce and use a small amount of it too.

          Estrogen is the major female hormones. The major amount of the estrogen is produced by the ovaries but small amounts are produced in the adrenal glands and fat cells. During pregnancy, the placenta also makes estrogen. Estrogen plays a big role in reproduction and sexual development, including puberty, menstruation, pregnancy and menopause.

          The ovaries also produces the progesterone after ovulation and during pregnancy, the placenta also produces some. Progesterone plays a role in preparing the lining of the uterus for a fertilized egg, supporting pregnancy and suppressing of estrogen production after ovulation.

          Testosterone is a male sex hormone that is important for sexual and reproductive development. It is responsible for development of male sex organs before birth as well as development of other secondary characteristics.

1.2     STATEMENT OF THE PROBLEM

          Alkaloids have been reported to show varying effects on the serum hormone levels. Rauwolfia vomitoria has a vast composition of alkaloids and is potent in treatment and management of various ailments. However, there is not enough information as to the effect of Rauwolfia vomitoria root bark extract on the levels of sex hormones.

1.3     AIM AND OBJECTIVES OF THE STUDY

The aim of the study is to evaluate the effect of Rauwolfia vomitoria root bark extract on male and female sex hormones.

1.4    SIGNIFICANCE OF THE STUDY

The result from this study will add more knowledge to our existing biomedical and pharmacological potentials of Rauwolfia vomitoria and this may help open up new avenues of investigation for researchers.

1.5     JUSTIFICATION OF THE STUDY

Medicinal plants have received a great deal of attention due to their possible beneficial as well as adverse effects. Some of these plants are known to possess anti- fertility effect through their action on hypothlamo-pituitary-gonadal axis or direct hormonal effects on reproductive organs resulting in inhibition of ovarian steroidogenesis.  Sex hormones are natural substances produced by the body that helps relay messages between cells and organs and affect development of sexual organs and other secondary sexual characteristics. Alteration in the levels of these sex hormones may lead to infertilty, abortion, abnormal development of sexual characteristics and sexual organs in male, hence the need for use of medicinal plants as a means of regulating hormonal levels by way of increasing or decreasing it.

1.6     SCOPE OF THE STUDY

The scope of the study includes:

i.        Administration of ethanol extract of Rauwolfia vomitoria to male and female albino Wistar rats depending on body weight

ii.       Collection of blood by cardiac puncture from anaesthetized experimental rats

iii.      Separation of serum by centrifugation

iv.      Determination of biochemical parameters