BS1060 Notes
Endocrinology
The endocrine system is everything that involves hormones
It is made up of the pituitary glands and hypothalamus in the brain.
Thyroid and Thymus. Adrenal glands and Pancreas as well as the gonads of both sexes.
Exocrine cells excrete substances onto the surface of the body.
Endocrine cells are completely sealed into the body, they have excretory cells that put
substances in the body. This is called exocytosis.
The release of these hormones is controlled by neurotransmitters.
Nervous system
• Quick
• Short term effect
• Single target organ
Endocrine System
• Slower
• Long term effect
• Affects the whole body
There are multiple methods used to for cell-to-cell messaging using hormones.
Autocrine, Paracrine, Endocrine and Neurocrine. Theres a table for this in the PDF
There is water soluble hormones and lipid soluble hormones. Each of them have differing
methods of how they enter the cell. Can be found in PDF.
Number of hormones is determined by
1) Rate of production: Synthesis & secretion, the most highly regulated aspect of hormonal
control.
2) Rate of delivery: Higher blood flow to a particular organ will deliver more hormone.
3) Rate of degradation: Hormones are metabolized and excreted from the body.
There are both negative and positive feedback loops which regulate the number of different
hormones
Calcium homeostasis is important for the function of the body. This is due to its role in
signalling and bone formation.
This homeostasis is controlled by the parathyroid hormones.
, This can increase the amount of calcium in the body while decreasing the amount of
phosphorus.
The parathyroid can target the GI tract to increase its absorption of both. It can target the
Kidney’s to reabsorb more calcium. Finally, it can target the osteoclasts in the bones for
more calcium as well.
Bone is made up of Osteons. There is a fast and slow exchange of calcium between bone
and blood plasma. Blood flows through the bone where this happens.
Fast is done where calcium moves from the layer of bone beneath the mineralized bone.
Slow is done where calcium moves from the mineralized layer of bone on the top.
Vitamin D needs to be activated in order to be useful
This is key in controlling the balance of calcium ions in the body
Calcitonin is a peptide hormone that is created when there is a high level of calcium ions in
the blood. GI hormones will trigger this as well. This hormone reduces the amount of
Calcium and phosphate ions in the blood.
Various physiological processes are controlled by the pituitary glands.
This is beneath the hypothalamus. It is made up of the Anterior and the posterior glands.
The posterior glands works by releasing ADH into the blood stream. This enables control of
things like milk secretion and water homeostasis
The anterior glands acts on 7 trophic hormones from the hypothalamus.
The anterior glands then produces the hormones that are needed.
There is a table showing the functions that the glands can do on the PDF
The pituitary glands is regulated by a negative feedback loop
Growth hormone is the most important hormone post-natel.
It is regulated by both long loop and short loop negative feedback
Long loop
Mediated by insulin-like growth factors (IGFs)
•Inhibit the release of growth hormone releasing hormone (GHRH)
•Inhibit the action of GHRH in the anterior pituitary
•Stimulates the release of somatostatin
GH secretion is influenced by many factors CNS regulates GH secretion via inputs into the
hypothalamus effecting GHRH and somatostatin levels:
• Surge in GH secretion after onset of deep sleep
Endocrinology
The endocrine system is everything that involves hormones
It is made up of the pituitary glands and hypothalamus in the brain.
Thyroid and Thymus. Adrenal glands and Pancreas as well as the gonads of both sexes.
Exocrine cells excrete substances onto the surface of the body.
Endocrine cells are completely sealed into the body, they have excretory cells that put
substances in the body. This is called exocytosis.
The release of these hormones is controlled by neurotransmitters.
Nervous system
• Quick
• Short term effect
• Single target organ
Endocrine System
• Slower
• Long term effect
• Affects the whole body
There are multiple methods used to for cell-to-cell messaging using hormones.
Autocrine, Paracrine, Endocrine and Neurocrine. Theres a table for this in the PDF
There is water soluble hormones and lipid soluble hormones. Each of them have differing
methods of how they enter the cell. Can be found in PDF.
Number of hormones is determined by
1) Rate of production: Synthesis & secretion, the most highly regulated aspect of hormonal
control.
2) Rate of delivery: Higher blood flow to a particular organ will deliver more hormone.
3) Rate of degradation: Hormones are metabolized and excreted from the body.
There are both negative and positive feedback loops which regulate the number of different
hormones
Calcium homeostasis is important for the function of the body. This is due to its role in
signalling and bone formation.
This homeostasis is controlled by the parathyroid hormones.
, This can increase the amount of calcium in the body while decreasing the amount of
phosphorus.
The parathyroid can target the GI tract to increase its absorption of both. It can target the
Kidney’s to reabsorb more calcium. Finally, it can target the osteoclasts in the bones for
more calcium as well.
Bone is made up of Osteons. There is a fast and slow exchange of calcium between bone
and blood plasma. Blood flows through the bone where this happens.
Fast is done where calcium moves from the layer of bone beneath the mineralized bone.
Slow is done where calcium moves from the mineralized layer of bone on the top.
Vitamin D needs to be activated in order to be useful
This is key in controlling the balance of calcium ions in the body
Calcitonin is a peptide hormone that is created when there is a high level of calcium ions in
the blood. GI hormones will trigger this as well. This hormone reduces the amount of
Calcium and phosphate ions in the blood.
Various physiological processes are controlled by the pituitary glands.
This is beneath the hypothalamus. It is made up of the Anterior and the posterior glands.
The posterior glands works by releasing ADH into the blood stream. This enables control of
things like milk secretion and water homeostasis
The anterior glands acts on 7 trophic hormones from the hypothalamus.
The anterior glands then produces the hormones that are needed.
There is a table showing the functions that the glands can do on the PDF
The pituitary glands is regulated by a negative feedback loop
Growth hormone is the most important hormone post-natel.
It is regulated by both long loop and short loop negative feedback
Long loop
Mediated by insulin-like growth factors (IGFs)
•Inhibit the release of growth hormone releasing hormone (GHRH)
•Inhibit the action of GHRH in the anterior pituitary
•Stimulates the release of somatostatin
GH secretion is influenced by many factors CNS regulates GH secretion via inputs into the
hypothalamus effecting GHRH and somatostatin levels:
• Surge in GH secretion after onset of deep sleep
