Bio 1-L24- Endocrine Regulation of Physiological Functions!!

how do endocrine signalling work

• cells make hormones stored in glands

• released and diffused throughout blood by receptors binding to the hormones

types of hormones

• steroid hormones- cortisol- lipid soluable-

• amine hormones- noradrenaline- water soluble

• polypeptides- water soluble

how do lipid soluble hormones work?

• hormone enters the cell

• hits target cell and binds to receptor protein- nucleus/cytoplasm

• gene expression

how do water soluble hormones work?

• hormone secreted

• signal on the surface membrane

• will trigger intercellular cascade- we get gene expression

example of stress response signalling

• adrenaline

• G protein coupled receptor- cascade and will activate protein kinase

• want to move mobilised glucose

what are endocrine tissues and organs

• pineal gland

• hypothalamus

• thyroid

• pancreas

• ovaries

• testes

• heart

• kidneys

when is secretin released and why?

• stimulus is low pH in duodenum- from S cells

• stimulates pancreatic sells to make bicarbonate

when is oxytocin released and what type of signalling?

• neuroendocrine- hypothalamus

• stimulus from baby suckling- stimulates secretion from hypothalamus

• finds target cell in mammary gland

how are endocrine and nervous system coordinated?

• pituitary- master gland and controls every other gland

• hypothalamus coordinates signalling

posterior pituitary- what is it etc

• stores and secretes hormones made by the hypothalamus

what does ADH do

• constricts blood vessels acts on kdineys

• changes amount of water reabsorbed

what does the topic hormone do

• help with secretion of other hormones

• FSH and LH- targets organs- testes and ovaries

what do nootropic hormones do

• does not cause the secretion of other hormones

• prolactin- production of milk

example: thyroid gland hormone

• hypothalamus regulates secretion of hormones

• if there’s a drop- release TRH which stimulates TSH

• TSH stimulates release of thyroid hormones from the thyroid gland

what do adrenal glands do?

• on top of kidneys

• has adrenal medullar and adrenal cortex(outer)

• medulla- secretes adrenaline- fight or flight

• cortex- corticosteroids- influece glucose metabolism etc

what hormones have multiple effects

• adrenaline

• can help break down glycogen- blood glucose increase

• increase blood flow to skeletal muscle

• blood vessels in intestine- give skeletal muscle blood- reduce blood to the gut

sex hormones in sexes

• female- oestrogen and progesterone

• androgens

what do the testes synthesise

• androgens such as testoterone

• secondary puberty- important for sperm

female cycle-

• in ovaries- follicles get stimulated and becomes mature- burst of FSH causes ovulation

• ova finds its way down

• LH- important in corpus lutes- secretes progesterone

• when progesterone drops- shedding of uterine lining

what does progesterone do

• prepared the uterus for pregnancy

endocrine disorders

• insufficientt iodine disorders

• growth disorders- abnormal growth etc