Topic 5 - Growth Hormone Part 1 Flashcards
Hypothalamus
A region of forebrain below the thalamus that coordinates both the autonomic NS and the activity of the pituitary, controlling body temp, thirst, hunger and other homeostasis systems and involved in sleep and emotional activity
Pituitary
The major endocrine gland. It is a pea-sized body attached to the base of the brain, the pituitary is important in controlling growth and development and the functioning of the other endocrine glandes
What does the hypothalamus intergrate and where does it send it?
Environmental signals and sends them to the pituitary gland
What secretes hormones in the hypothalamus?
Neurons
Where do hormones travel after the hypothalamus?
They travel down the portal hypophysial vessel to the anterior pituitary
How do you secrete hormones?
Stimulate of inhibit anterior pituitary cells
What does the hypothalamus do?
Balances hormones
What are 5 anterior pituitary hormones and what do they secrete?
- Somatotrophs –> GH
- Lactotrophs –> PRL
- Thyrotrophs –> TSH
- Corticotrophs –> (adrenocorticotrophic hormone)
- Gonadotrophs –> LH and FSH
GH is what kind of hormone?
Protein hormone
What happens at the mRNA level of regulation? (2)
- Transcription
2. Splicing
What happens at the protein level of regulation? (2)
- Cleavage
2. Post-translational modifications
What happens at the secretion level of regulation?
Stimulus
What does the direct effect of GH effect?
Metabolism and protein synthesis
What does the indirect effect of GH effect?
Growth
What does GH do?
Stimulates break down of triglycerides for energy and suppresses up of circulating lipids
What is insulin used for? (2)
- Glucose
2. Fat storage
How does GH effect protein synthesis?
It increases amino acid uptake and accelerating transcription and translation of mRNA
What does GH suppress? (2)
- Suppresses the ability of insulin to stimulate uptake of glucose in peripheral tissues
- Suppresses insulins ability to enhance glycogen synthesis in the liver
What does GH decrease and increase?
Decrease fat and carbs
Increase protein
What causes GH to decline?
Age
IGF-1
Insulin-like growth factor 1
Where is IGF-1 secreted from?
Liver and other tissues in response to GH