ABSTRACT
Phytoestrogens are natural estrogenic agents present in plants.
Phytoestrogens are any plant compounds structurally and/or functionally
similar to ovarian and placental estrogens and their active metabolites.Sesamumindicum is
one of the phytoestrogen containing seeds used by man for food and
medicinal purposes. Researches have shown that phytoestrogens present in
plants might have both fertility-enhancing and anti-fertility effects.
Present studies evaluated the mean lethal dose of the hydroethanolic
seed extract of sesame and the effects of the extract on some
reproductive parameters of female albino rats. Cycling female rats
weighing 120-140g were used for the studies. For the ovulation study,
twenty (20) female rats were divided into four (4) groups of five (5)
rats groups II, III and IV received 100, 300 and 500 mg/kg of seeds
extract of S. indicumorally respectively. The animals were
dosed at 4 hourly interval for 24 hours. Animals were sacrificed the
following morning. For the hormonal level study, the extract was
administered orally to three (3) experimental groups of five (5) female
rats at doses of 100, 300 and 500 mg/kg once daily while control group
received distilled water at dose of 1ml/kg for 30 days. The animals were
subsequently sacrificed in the morning of the day after the last
administration. For studies on pregnancy outcome, the extract was
administered orally four (4) groups of five (5) pregnant rats each.
Administration was done once daily from day 1-7 of pregnancy as follows:
group I: distilled water (1 ml/kg), group II: 100 mg/kg, group III: 300
mg/kg and group IV 500 mg/kg respectively, with seeds extract of S. indicum.
The number of ovarian follicles was significantly higher (p <
0.05) in group IV than control rats (31.40 + 3.20 vs 22.80 +4.22), while
groups II and III had lower number of follicles than control rats
(14.80 + 2.40, 19.80 + 3.40 vs 22.80 + 4.22).
CHAPTER ONE
1.0 INTRODUCTION
Hormones are intimately involved in our sex lives, as well as all
other aspects of ourlives, from intrauterine life to death. Of these,
the most important are the socalledsex hormones. Mammalian sexual
behavior is controlled by these gonadal steroids actingat the level of
the central nervous system. They are divided into the male hormones
(orandrogens) and the female hormones. While, both sexes produce both
types, those corresponding to the appropriate sex predominate (in most
cases) (Wierman, 2007). Women produce a number of hormones specific to
them, particularly during their childbearing years. The two best-known
female hormones are estrogen and progesterone, sometimes also referred
to as sex hormones. These are produced predominantly in the ovaries,
although the adrenal glands and the placenta of pregnant women also
secrete them. Some research has indicated that estrogen can be
manufactured in the brain as well (Haybach, 2010).
The main female hormone is estrogen. Estrogens display one common
biologic activity, the ability to stimulate growth and maintain the
female sex characteristics (Goldzieher and Castracane, 2008). Estrogen
stimulates the development of the female sex organs both within the
fetus and at puberty, creating her femaleness, her rounded breasts
andcurvy hips. It also enhances pheromone secretion and 'invitational
behavior and her yearning for sexual contact. Estrogen levels peak just
prior to ovulation. They drop off precipitously during menopause, with
consequent vaginal dryness and atrophy and increased risk of
osteoporosis and heart disease (Wierman, 2007).