Hypothalamus and Pituitary Gland Flashcards
What type if tissue is hypothalamus
Neural
How does it connect to pituitary
Infandibulum
Neural to PP (hormone situated in hypothalamus and stored in axons in PP which is extension of neural tissue)
Endocrine connection to AP
Where is pituitary situated
Sphenoid bone
What can hormones be
Trophic
Non-trhopic
What are trophic hormones
Govern release of another hormone
Neurohormone goes to AP and govern release of another hormone
What are non-trophic hormones
Released into blood for action
e.g Neurone hormones produced in hypothalamus travel to PP via axons
What are all hormones released by hypothalamus and PP
Neurohormone
What are all hormones released by AP
Endocrine
What 5 releasing hormones does hypothalamus release
Thyrotrophin releasing hormone Corticotrophin releasing hormone Growth hormone releasing hormone Gonadotrophin releasing hormone Prolactin releasing hormone
What 2 inhibiting hormones does hypothalamus release
Growth hormone inhibiting hormone (somatostatin)
Prolactin inhibiting hormone (dopamine)
What type of hormones are they
All peptide except dopamine which is an AMINE
Action of thyrotrophin releasing hormone
Release of thyroid stimulating hormone from AP
Travel to thyroid gland to release thyroid hormone
Action of corticotrophin releasing hormone
Release of corticotrophin from AP
Goes to adrenal cortex for cortisol release
Action of growth hormone releasing hormone
Release of growth hormone from AP
Goes to liver for IGF-1 release OR direct tissue metabolism
Another name for growth hormone
Somatotrophin
Action of gonadotrophin releasing hormone
Goes to gonads for sex hormone release
Action of prolactin releasing hormone / dopamine
Goes to mammilary glands and stimulates prolactin release for lactation
What hormones does PP secrete
Vasopressin (ADH)
Oxytocin
Action of ADH
Triggered by increased osmolality or decreased plasma volume
Acts on collecting duct to increase water reabsorption
Smooth muscle contraction to increase BP
Action of oxytocin
Triggered by labour or sucking
Uterine contraction
Milk ejection
What can cause issues
Hyposecretion
Hypersecretion
Hyporesponse - alterations in receptors
Hyperresponse - permissive
What type of disorders do you get
Primary - disorders in cells that secrete hormone
Secondary - too much or too little trophic hormone from pituitary
Tertiary - hypothalamic (rare)
