Ageing Endocrine System Flashcards
what do neurosecretary cells do
release stimulating and inhibiting hormones, which are secreted into the pituitary portal system.
ANTERIOR pituitary hormones
- Gonadotropins (fsh and lh)
- Growth hormone (bone and tissue)
- Prolactin (milk production)
- Adenocorticotropic
- Thyroid stimulating
POSTERIOR pituitary hormones
- Oxytocin (mammary glands and smooth muscle cells In uterus)
- ADH
what are the general ageing endocrine changes
most glands show atrophy and decreases in secretion.
most apparent in
glucose homeostasis / reproductive function / calcium metabolism
glucose homeostasis changes
increased risk of type 2 diabetes from
- decreased physical activity
- increased adiposity
- comorbidities and genetics and medication.
islets of langerhan show little change – decrease in glucose tolerance from decreased response to blood glucose. Inadequate insulin secretion from from decreased cell membrane responsiveness to insulin.
what is the climactic period
reduced reproductive capacity with ceassation of E2 and progesterone. negative feedback resulting in increases in FSH and LH.
What are the female reproductive changes
- thinning and greying of pubic hair
- loss of sub q on genitalia
- decreased skin elasticity
- deceased glandular tissue in breast
- ovaries and uterus decease in size n weight
- atrophy of vaginal tissues form low E2 / dryness and thinning
rapid decline of oocyte pool after menopause
What are the male reproductive changes
- T4 deceases / testes become smaller
- erections less firm
- fewer viable sperm and less motility
- decreased seminal fluid ejected
- may not orgasm with sex
- enlarged prostate gland / inhibiting the urethera
what are the signs of the andropause
- impotence
- gynocomastia
- adenocarcinoma
- prostate hypertrophy
- testicular hypertrophy
what are the vitamin D and Calcium homeostasis changes
resistance to vitamin D in the small intestine, so less calcium is reabsorbed.
parathyroid hormone resistance in the kidney reduced vitamin d sensitivity and therefore reduces calcium absorption in the renal tubules
decreased effect of vitamin d on skeletal muscle and bone
what are the ageing effects of the adrenal cortex
- 25% reduction of cortisol
- plasma cortisol level unchanged from deceased renal clearance
- decreased aldosterone production
decreased RAAS / leading to orthostatic hypotension
ageing adrenal medulla
increased catecholamine and norepinephrine in elderly but responsiveness to norepinephrine will decease along with nerve ending production of norepinephrine. leading to delayed BP to standing up / orthostatic hypotension.
ageing thyroid
- increased infiltration of lymphatics and decreased in glandular cells. Association from an autoimmune destruction of gland.
- Hypothyroidism from reduced t4
- Increased nodularity in 27% of thyroid disections
ageing GH
- Reduced by 65% of early adulthood by 65
- Considererd as therpay for cancer and pancreas problems
- Fails to be supressed by nutrients (normally is by glucose in health) – elderly is not
ageing ADH
decreased ability to concentrate urine from, increasing renal tubular resistance to ADH and decreased tubular sensitivity.
