chemical coordination Flashcards
T4 hormone is (thyroid hormone)
peptide hormones
In some hypersensitivity reactions, antibodies circulating in the blood can bind to and activate hormone receptors. For example, in Graves disease, antibodies can activate cell surface receptors for thyroid stimulating hormone (TSH) on thyroid tissue and cause excessive secretion of thyroid hormones. Based on this information, TSH most likely:
Is a peptide hormone
peptide hormones
- ANTERIOR PITUITARY:
FSH
LH
ACTH
TSH
Prolactin
Endorphins
Growth
Hormones - POSTERIOR PITUITARY:
ADH
Oxytocin - PARATHYROID:
PTH
4.PANCREAS:
Glucagon
Insulin - THYROID:
Calcitonin
types of chemical natured hormone
(i) Proteins (e.g. insulin and glucagon.)
(ii) Amino acids & derivatives (e.g. Thyroxin, epinephrine and norepinephrine)
(iii) Polypeptides (e.g. vasopressin or anti-diuretic hormone and oxytocin)
(iv) Steroids (e.g. estrogens, testosterone and cortisone)
role of hypothalamus in endocrine system
Nerve cells in the hypothalamus produce and secrete a variety of hormones. One of the nerve clusters synthesizes oxytocin and antidiuretic hormone (ADH)vasopressin. These hormones travel down and are stored in the nerve endings located in the posterior pituitary. Upon proper stimulation from the hypothalamus, oxytocin and vasopressin are released into the blood supply of the posterior pituitary. Other nerve clusters in the hypothalamus produce and secrete a battery of releasing and inhibiting hormones. These hormones are carried by the blood to the anterior pituitary. There they regulate the secretion u various tropic hormones, growth hormone, and Prolactin manufactured by the anterior pituitary cells.
Anterior pituitary lobe
Also known as master gland.This is because that in addition to producing
primary hormones it produces the tropic hormones which control the secretion of hormones of
other endocrine glands
anterior lobe secretes
- Somatotrophin (STH)
- Thyroid Stimulating Hormone
- Adrenocorticotrophic Hormone (ACTH)
- Gonadotrophic Hormones
- Prolactin (PRL)
6.Follicle-stimulating hormone (FSH) - Luteinising hormone (LH)
Acromegaly
Acromegaly is a hormonal disorder that develops when your pituitary gland produces too much growth hormone during adulthood. When you have too much growth hormone, your bones increase in size. In childhood, this leads to increased height and is called gigantism. But in adulthood, a change in height doesn’t occur.
Dwarfism
Dwarfism is short stature that results from a genetic or medical condition.
Endocrine Glands:
The endocrine or ductless glands are (with a few exceptions) discrete group of cells which make specific chemical compounds called hormones (In Greek hormone mean) exciting or setting in motion).
Hormone:
Hormones are organic compounds of varying structural complexity. They are poured directly and are transported by blood to respective target tissues.
Function:
The hormones affect the target cells. To affect the target cells they work in the following. They do not initiate new biochemical reactions. However they regulate enzymatic and other chemical reactions, already present. They may either stimulate or inhibit a function. Hormones may also control some long term changes. For example rate of growth, ate of metabolic activity and sexual maturity.
Chemical Nature of Hormones:
Chemically hormones may be of following four types:
(i) Proteins (e.g. insulin and glucagon.)
(ii) Amino acids & derivatives (e.g. Thyroxin, epinephrine and norepinephrine)
(iii) Polypeptides (e.g. vasopressin or anti-diuretic hormone and oxytocin) and Steroids (e.g. estrogens, testosterone and cortisone)
Role of Hypothalamus in Endocrine System:
It is part of the fore brain. Here many of the sensory stimuli of the nervous system are converted into hormonal responses. Nerve cells in the hypothalamus produce and secrete a variety of hormones. One of the nerve clusters synthesizes oxytocin and antidiuretic hormone (ADH)vasopressin. These hormones travel down and are stored in the nerve endings located in the posterior pituitary. Upon proper stimulation from the hypothalamus, oxytocin and vasopressin are released into the blood supply of the posterior pituitary. Other nerve clusters in the hypothalamus produce and secrete a battery of releasing and inhibiting hormones. These hormones are carried by the blood to the anterior pituitary. There they regulate the secretion u various tropic hormones, growth hormone, and Prolactin manufactured by the anterior pituitary cells.
The Pituitary Gland:
In the pituitary gland (hypophysis cerebri) is an ovoid structure. It is about 0.5 gm in the adult and is connected to brain through a short stalk (the infundibulum). It has three lobes which are anterior ,median and posterior.
Anterior Lobe
The anterior lobe is also called as the master gland. This is because that in addition to producing primary hormones it produces the tropic hormones which control the secretion of hormones of other endocrine glands
- Somatotrophin (STH):
Release:
Somatotrophin releasing factor (SRF) is secreted from hypothalamus through nut the life.
Functions: The main function is growth. When growth has mostly ceased after adolescence, the hormone continues to promote protein synthesis throughout the body.
Disorders:
(i) If this hormone is produced in excess during early life, it leads to Gigantism as a result there is abnormal development of hands, feet, jaw etc. (known as Acromegaly).
(ii) If there is under-secretion,Dwarfism results in addition to other symptoms associated with lack of thyroid and adrenal hormone.
- Thyroid Stimulating Hormone:
Release:
Release of thryotrophin releasing factor from the hypothalamus is controlled by the levels of thyroxin in the blood. In the presence of low levels of thyroxin, there is increasing production of TSH and viceversa.
Functions:
It is secreted throughout life but particularly reaches high levels during the periods of rapid growth and development. It acts directly on the cells of the thyroid gland increasing both their numbers and their secretary activity.
