Hypothalamus and Pituitary Gland Flashcards
How are the hypothalamus and pituitary gland connected to each other?
Infundibulum (pituitary stalk)
What are the different types of pituitary tissue?
Anterior
Posterior
What type of hormones are released by the hypothalamus?
Neurohormones
What type of hormones are released by the posterior pituitary?
Neurohormones
What type of hormones are released by the anterior pituitary?
Endocrine
What are the two forms of neurohormones released by the hypothalamus?
Trophic
Non-trophic
What are trophic hormones?
Neurohormones secreted into capillaries travelling to anterior pituitary
What are non trophic hormones?
Neurohormones produced in hypothalamus and travel to posterior pituitary then released into blood
What are the trophic hormones that control secretion of other endocrine glands?
Thyrotrophin releasing hormone (TRH) Corticotropin releasing hormone (CRH) Growth hormone releasing hormone (GHRH) Gonadotrophin releasing hormone (GRH) Prolactin releasing hormone (PRH)
What are the anterior pituitary trophic hormones that inhibit the release of an
Growth hormone inhibiting hormone (GHIH)
Dopamine/ Prolactin inhibiting hormone (PIH)
What is the hypothalamo-hypophyseal portal system?
Network of vessels which transfer trophic hormones from hypothalamus to anterior pituitary
Where are hormones released from in the hypothalamo-hypophyseal portal system?
Median eminence
What are the anterior pituitary trophic hormones that control secretion of other endocrine glands?
Thyroid stimulating hormone (TSH) Adrenocorticotrophic hormone (ACTH) Follicle stimulating hormone (FSH) Luteinising hormone (LH) Growth hormone (GH)
What anterior pituitary trophic hormone directly stimulates milk production from breast during lactation?
Prolactin
What are the hormones that the posterior pituitary stores and releases?
Vasopressin (Anti diuretic hormone)
Oxytocin
(Both peptide neurohormones)
What is the main function of vasopressin?
Regulates water balance
What triggers the release of vasopressin?
Increased plasma osmolarity
Decreased volume/blood pressure
What is the main function of oxytocin?
Milk ejection and uterine contraction
What triggers the release of oxytocin?
Labour
Suckling
What is a first degree endocrine disorder?
Defect is in the cells that secrete the hormone
What is a second degree endocrine disorder?
Too little/much trophic hormone from pituitary
What is a third degree endocrine disorder?
Relate to hypothalamic defects
