2 Endorine System and Endocrine Disruptors
2.1 Endocrine System
The endocrine system consists of glands, hormones, and receptors. Endocrine glands
include the hypothalamus, pineal, pituitary, thyroid, parathyroid, thymus, adrenal,
ovaries, prostate, and testes [8].
The pituitary gland acts as the control center, telling the other glands when to send
their signals and how much hormone to send. The pituitary gets its cues from the
hypothalamus, which acts as a regulator, telling the pituitary to increase hormone
production or to slow it down and shut it off. These messages travel back and forth
continuously throughout all parts of an organism, keeping everything balanced and
coordinated.
The glands produce hormones, such as adrenocorticotropic hormone (ACTH),
corticosteroid, adrenaline, estrogen, testosterone, androgen, insulin, triiodothyronine, and thyroxin.
Hormones are involved in just about every biological function. They are better
known as the body’s chemical messengers because they travel through the bloodstream and cause responses in other parts of the body. The amount of hormone that
an animal’s body produces depends upon the stimuli that its body receives. They
also can work at astonishingly low concentrations – in parts per billion or even
trillion. Hormones regulate [8]:
1. Reproduction and embryo development
2. Growth and maturation
3. Energy production, use, and storage
4. Electrolytes – the balance and maintenance of water and salt
5. Reaction to stimuli, such as fright and excitement
6. Behavior of human beings and animals
Receptors, which are in the cells of various target organs and tissues, recognize
and respond to the hormones. Receptors are a part of a complex biological
feedback system that regulates the response. Any disruption to the balance can
cause changes to take place in these reactions.
2.2 Endocrine Disruptors
Endocrine disruptors are synthetic or naturally occurring chemicals that interfere
with the balance of normal hormone functions in animals, including humans. This
imbalance can cause various abnormalities of the reproductive system, such as the
feminization of males and the masculinization of females. Among other abnormalities, they also can cause enlargement of the thyroid gland, birth defects, behavioral
changes, depressed immune systems, and an increased vulnerability to disease.
174
N. K. Shammas et al.
2.1 Endocrine System
The endocrine system consists of glands, hormones, and receptors. Endocrine glands
include the hypothalamus, pineal, pituitary, thyroid, parathyroid, thymus, adrenal,
ovaries, prostate, and testes [8].
The pituitary gland acts as the control center, telling the other glands when to send
their signals and how much hormone to send. The pituitary gets its cues from the
hypothalamus, which acts as a regulator, telling the pituitary to increase hormone
production or to slow it down and shut it off. These messages travel back and forth
continuously throughout all parts of an organism, keeping everything balanced and
coordinated.
The glands produce hormones, such as adrenocorticotropic hormone (ACTH),
corticosteroid, adrenaline, estrogen, testosterone, androgen, insulin, triiodothyronine, and thyroxin.
Hormones are involved in just about every biological function. They are better
known as the body’s chemical messengers because they travel through the bloodstream and cause responses in other parts of the body. The amount of hormone that
an animal’s body produces depends upon the stimuli that its body receives. They
also can work at astonishingly low concentrations – in parts per billion or even
trillion. Hormones regulate [8]:
1. Reproduction and embryo development
2. Growth and maturation
3. Energy production, use, and storage
4. Electrolytes – the balance and maintenance of water and salt
5. Reaction to stimuli, such as fright and excitement
6. Behavior of human beings and animals
Receptors, which are in the cells of various target organs and tissues, recognize
and respond to the hormones. Receptors are a part of a complex biological
feedback system that regulates the response. Any disruption to the balance can
cause changes to take place in these reactions.
2.2 Endocrine Disruptors
Endocrine disruptors are synthetic or naturally occurring chemicals that interfere
with the balance of normal hormone functions in animals, including humans. This
imbalance can cause various abnormalities of the reproductive system, such as the
feminization of males and the masculinization of females. Among other abnormalities, they also can cause enlargement of the thyroid gland, birth defects, behavioral
changes, depressed immune systems, and an increased vulnerability to disease.
174
N. K. Shammas et al.