7.5 Flashcards
Describe the metabolic actions of growth hormone
- Increased protein synthesis
- Decreased proteloysis
- Increased lipolysis
- Gluconeogenesis
- Decreased muscle insulin sensitivity
What type of hormone is growth hormone?
Peptide (think about what kinds of receptors this could bind to)
What stimuli can lead to release of growth hormone?
- Exercise
- Stress
- Hypoglycaemia
- Fasting (since IGF-1 is low)
What are some stimuli that decrease growth hormone secretion?
- IGF
- GH (stimulate GHIH)
What is another name for somatomedins?
Insulin-like growth factors
What is another name for somatomedins?
Insulin-like growth factors
Describe the growth-promoting actions of growth hormone. Which hormone does this largely occur through?
- Increased protein synthesis
- Decreased proteolysis
- Hyperplasia
- Hypertrophy
Occurs largely via IGF-1
Describe action of GH on bone growth
- Stimulates proliferation of epiphyseal cartilage
- Increased bone remodelling
- Proliferation of osteoblasts
What is a potential cause of GH hypersecretion?
Pituitary tumour (during childhood: gigantism, in adulthood: acromegaly)
What are some potential causes of GH hyposecretion?
- Lack of GHRH
- Hypothalamic tumour/injury
- Social/psychological factors
Key role of FSH in males
Sperm production
Key role of LH in males
Testosterone secretion
Key role of FSH In females
- Follicle development
- LH receptors on dominant follicle
- Oestrogen secretion
Key role of LH in females
- Acute surge in ovulation
- Maintains corpus luteum
How is gonadotropin release mediated?
Pulsatile secretion pattern of GnRH, which is in turn regulated by negative feedback from steroid and peptide hormones (oestrogen and testosterone)
