Endocrine System Flashcards
What is paracrine cellular communication
Hormones released by one cell that stimulate only local cell populations
What is humoral control
Control of hormones by circulation ions or nutrients
What does thyroid hormone (T4) do
Increase metabolic rate in all cells through gene regulation
Thyroid hormone is released by the
Thyroid gland
How would the body respond to low calcium
Increased parathyroid release which increases the breakdown of bone
Which hormones are made in the adrenal cortex
Aldosterone and cortisol
What does aldosterone do
Increases the reuptake of sodium in the kidneyt
How does the hypothalamus communicate with the anterior pituitary gland
Through the hypothalamic hypophyseal portal system
What is adrenocorticotropic hormone (ACTH)
It is a stimulating hormone produced by the anterior pituitary
Where is the pituitary gland located
The brain
Describe 2 ways a hormone can alter the function of a target cell
1) bind to a receptor on the outside of the cell (G-protein coupled) that implements a sequence of reactions inside the cell that dictates a certain action/function
2)enter the cell and instigate a change in a receptor in the nucleons causing a shift in the proteins being created by the cell
How does the endocrine act
Systematically
How are hormones activated
Humoral control
Response to stress and anxiety
What is beneficial about the distribution of hormones
1 - can travel large distances in a short amount of time
2 - the hormones are potent so only a small amount is needed
Describe how hormones bind on the outside of the cell
Attaches to active site of receptor
Triggers release of G protein
Activates adenlyl cyclise
Adenlyl cyclise converts ATP to cyclic AMP
AMP activate PKA (protein kinase A)
PKA can phosphorylase a protein
Causing a mechanism within the cell the change
Describe how hormones causes a shift in the proteins in the cell (steroid hormones)
Steroid passes into the cytoplasm of the cell
It binds to a receptor
Enters the nucleus of the cell in its activated form
Initiates a change in the transcription of new proteins from the DNA specific hormone response elements
MRNA will exit the nucleus and travel to the ribosome for translation
A new protein will be synthesized that can alter a cell function
Which hormone is lipid soluble
Steroid
What does lipid soluble mean
Can pass into the cytoplasm of the cell
When does the nervous system interplay with the endocrine system
When nervous signals stimulate hormone secretion
What does neuroendocrine mean
Nervous system interplays with the endocrine system
Where does neroendocrine happen
Hypothalamus
What can the pituitary gland stimulate
Hypothalamic pituitary adrenal (HPA)
Hypothalamic pituitary thyroid (HPT)
Hypothalamic pituitary gonodal (HPG)
Hypothalamic pituitry prolactin (HPP)
Which part of the pituitary gland contains its own secretory cells
Anterior
When does the anterior pituitary secrete their own hormones
When the hypothalamus sends hormones through the hypothalamic - hypophyseal portal system
What type of hormone is the one from the hypothalamus to the anterior pituitary gland
Releasing hormone
What does the releasing hormone from the hypothalamus to the anterior pituitary gland do
Signals the anterior pituitary gland to start producing hormones
When does the releasing hormone from the hypothalamus to the anterior pituitary gland change to a stimulating hormone
When the releasing hormone enters the systematic circulation as it travels to the site of action
What is the function of the posterior pituitary gland
To store hormones produces by the hypothalamus ready for the release into circulation when the signal arrives
What hormones does the anterior pituitary gland produce
Adrenocorticotropic hormone (ACTH)
Follicle stimulating hormone (FSH)
Luteinizing hormone (LH)
Melanocyte stimulating hormone (MSH)
Growth hormone (GH)
Prolactin (PRL)
What hormones does the posterior pituitary gland produce
Oxytocin
Anti-diuretic hormone (ADH)
What does oxytocin do
Initiates muscular contraction of the uterus and stimulates milk production during lactation
Increases testosterone in the testes
What does anti-diuretic hormone (ADH) do
Reduces water lose from the body to maintain plasma volume by promotion water re-uptake from the collecting ducts in the kidneys
What does the growth hormone do
Promotes cell division and proliferation
Stimulate break of fats for energy
Stimulates synthesis of glycogen
Promotes bone and cartilage growth
Stimulates uptake of amine acids and protein synthesis
When is ACTH released
After corticotropin has been secreted from the hypothalamus
What does ACTH do
Causes cortisol to be released from adrenal cortex
Which causes aldosterone to be released from adrenal cortex
This then binds directly to melanocytes of the skin
What is the function of melanocytes
To alter the production of melanin
What does melanocyte stimulating hormone (MSH) do
Regulates the function of skin pigment cells
What does the follicle stimulating hormone do
Initiates follicle growth in ovaries and oestrogen levels
Stimulates germinal epithelium growth in testes
What does the luteinizing hormone do
Causes oestrogen and testes to be secrted
What does prolactin do
Stimlulates lactation and inhibits FSH and gonadotropin releasing hormone
What two hormones does the thyroid glands produce
Thyroxine (T4)
Triiodothyronine (T3)
What are 3 possible diseases of the thyroid
Graves, hyperthyroidism and hypothyroidism
What effect does Graves’ disease have
Your immune system attacks your thyroid and it becomes over active
What effect does hyperthyroidism have
Thyroid gland produces too much thyroid hormone leading to weight loss, fast heart rate, sweating and nervousness
what is the target organ of TSH
thyroid gland
what is the target organ of ACTH
Adrenal gland
what is the target organ of growth hormones
whole body tissues and bone
what is the function of releasing/tropic hormones
trigger release the
