Lecture 26 Flashcards
What are the two types of diabetes mellitus?
Type 1 is hypo-secretion and type 2 is hyposensitive
What is hypo-secretion and what causes this condition?
Too little or no insulin secreted and is caused by destruction of pancreatic beta cells by the immune system.
What are some outcomes of hypo-secretion?
Glucosuria, polyuria, polydipsia (thirsty), diabetic neuropathy, heart problems, diabetic retinopathy, disrupted blood flow and many more.
What is the treatment for type 1 diabetes?
Insulin injections or infusion
What is hypo-sensitive and what causes this condition?
Too little or no response to insuin “insulin resistance” and is caused desensitisation of insulin receptor and is commonly associated with obesity.
What are some outcomes of type 2 diabetes?
The same as type 1 diabetes
What is the treatment of type 2 diabetes?
Changes in diet and exercise. Various medications
Where is the hypothalamus?
In the centre of the brain and inferior to it is the pituitary gland.
What are the two areas of pituitary gland called?
Anterior and posterior lobes.
How does the hypothalamus control the pituitary gland?
By activating the hypothalamus by neural input to get the pituitary gland to secrete hormones
Why can pituitary tumours be a problem?
There isn’t enough space for a tumour to grow so it pushes on the pituitary gland.
How is the hypothalamus connected to the posterior lobe?
By neurons, cells bodies in the hypothalamus, axons terminate in the posterior lobe.
Where are posterior pituitary hormones made?
In the hypothalamus
How do the hormones get sent to the posterior pituitary gland?
They travel down the axon and are stored at the axon terminals until required.
Where does the posterior pituitary gland release its hormones?
Straight into the blood
What are the two types of hormones released from the posterior pituitary gland?
Antidiuretic hormone (ADH) or oxytocin, each released by seperate neurons
What does the antidiuretic hormone do?
Stimulates the kidneys to reabsorb water ( the kidneys conserve water when the body dehydrates)
What does oxytocin hormone do?
Stimulates the contraction of uterine muscles during childbirth and stimulates milk release in breastfeeding
How is the anterior lobe of the pituitary gland connected to the hypothalamus?
Connected by blood vessels.
How does the hypothalamus get the anterior pituitary gland to release hormones?
Hypothalamic hormones simulate or inhibit release of stored hormones from specific anterior pituitary cells, by travelling through the blood and binding to cells with the right receptor in it and causes those cells to release their own hormones.
What does the anterior pituitary hormone do?
Stimulates a target organ to release another hormone
Can the pituitary hormone inhibit the hypothalamus?
Sometimes
In the hypothalamus what does it release to form growth hormone in the anterior pituitary gland?
Growth hormone releasing hormone
What does the growth hormone cause the release of?
It causes the release of somatomedian C from the liver
Does the somatomedin c feedback to the hypothalamus
Yes it inhibits the hypothalamus to tell it to stop releasing growth hormone releasing hormone.
What hormone is released when somatomedin C gives positive feedback?
Growth hormone inhibiting hormone. SS (Somatostatin)
What does the growth hormone inhibiting hormone do?
It prevents the anterior pituitary gland from releasing more growth hormones
What are some indirects effects of GH?
Promotes the growth of bones, muscles and other tissues by causing release of somatomedin C which promotes cell division.
What are the direct effects on GH for muscles?
Stimulates protein synthesis and inhibits cellular uptake of glucose
What are the direct effects on GH for the liver?
Stimulates glucose synthesis
What are the direct effects on GH for fats?
Increases triglyceride breakdown in the adipose tissue
Does Gh hormone have a long term or short term effect on growth?
Long term
Does GH hormone have a long term or short term effect on metabolism?
Short term
When does the growth hormone peak?
At night, because it gives your body a chance to repair while sleeping.
When do you have the most amounts of growth hormones?
When you hit puberty and degrades over time.
What are some growth hormone disorders?
Gigantism and dwarfism
What is gigantism?
Excess growth hormone, a result of a pituitary tumour which causes thickening of bone tissues. Can be over 7 foot tall.
What is dwarfism?
Not enough growth hormone, they are in proportion as they are growing equally but not enough to fully develop.
