The Anterior Pituitary Flashcards
What is the function of the pituitary gland
Secretes hormones in response from signals from the hypothalamus
How does the anterior pituitary receive blood
The anterior pituitary doesn’t have an arterial blood supply but receives blood from the portal venous circulation from the hypothalamus
What hormones are secreted by the anterior pituitary
Growth hormone
Thyroid stimulating hormone
Follicle stimulating hormone
Luteinising hormone
Adrenocorticotrophic hormone
Prolactin
Melanocyte stimulating hormone
How does the hypothalamus stimulate the release of hormones from the anterior pituitary
The hypothalamus releases hormones into surrounding interstitial fluid which permeate into nearby fenestrated capillaries which form the hypophyseal portal system which extends downs to the anterior pituitary. The anterior pituitary receives the hormones from the hypothalamus which stimulates the release of hormones into the systemic circulation
What is cortisols main functions
Glucose homeostasis
Lipolysis
Regulation of mood
What regulates the release of ACTH
ACTH is regulated by the release of the hypothalamic hormone CRH
What causes CRH to be released from the hypothalamus
Stress
Fear inducing simulation
Infection
Blood loss
What are the main actions of cortisol
Increases plasma glucose levels
Stimulated lipolysis in adipose tissue
Immunosuppression
Anti-inflammation
Protein and fat metabolism
Bone metabolism
Regulates calcium absorption from GIT
Regulates behaviour mood and cognition
What can reduced cortisol and aldosterone production be caused by
Addison’s disease
What is the function of LH in males
LH stimulates the leydig cells in the testes to produce testosterone
What is the function of FSH in males
FSH drives sperm production on Sertoli cells of the testes and the synthesis of proteins important of the production and action of steroid hormones
What is the function of LH and FSH in females
Both stimulate the ovary to produce mature gametes as well as synthesis and secrete oestrogens and progestins
How are LH and FSH regulated
GnRH is released from the hypothalamus and travels to the anterior pituitary where it binds to the gonadotropin cells on the surface to stimulate the production of LH and FSH which then act upon the gonads
What is growth hormone also known as
Somatotropin
What are the main functions of the growth hormone
Skeletal growth
Muscle strength
Bone density
Cardiac function
