Endocrine
The hypothalamic–pituitary axes, thyroid, adrenal, endocrine pancreas and calcium.
27 pages
Exam priority: high
- Actions of cortisolMechanism · Cortisol is the lasting stress hormone: it raises glucose, damps inflammation and keeps blood…
- Actions of thyroid hormonesMechanism · Thyroid hormones set the pace of metabolism: with too much everything speeds up, with too little…
- Aldosterone: actions and controlRegulation · Aldosterone makes the kidney keep sodium and excrete potassium and hydrogen
- Calcium regulation: PTH, vitamin D and calcitoninRegulation · When blood calcium falls, the parathyroid releases PTH, which pulls it from bone, saves it in…
- Islets and insulin: secretion and actionsRegulation · After a meal the pancreatic β cell releases insulin, which makes liver, muscle and fat store…
- Physiology of diabetes and ketoacidosisMechanism · In diabetes insulin is missing or does not work well: glucose stays in the blood and, if insulin…
- The HPA axis and its circadian rhythmRegulation · The brain sends CRH, the pituitary ACTH and the adrenal cortisol
- The hypothalamic–pituitary system: overviewConcept · The hypothalamus gives orders to the pituitary, and the pituitary drives the thyroid, adrenals…
- The thyroid axis: reading TSH and free T4Measurement · TSH is the thermostat: it rises when thyroid hormone is short and falls when there is too much
Exam priority: medium
- Appetite hormones: leptin, ghrelin and incretinsRegulation · Fat sends leptin to say «we have reserves»; the empty stomach sends ghrelin to say «eat»; the…
- Blood glucose, glucose tolerance test and HbA1cMeasurement · Three tests show how well the body handles sugar: a fasting level, a curve after a sugary drink…
- Bone remodelingMechanism · Bone is rebuilt all the time: some cells dig out old bone and others fill the hole with new bone
- Glucagon and the counter-regulatory hormonesRegulation · When glucose falls, glucagon and epinephrine raise it within minutes; cortisol and GH hold it up…
- Growth hormone and IGF-1Regulation · The pituitary releases growth hormone in pulses, mostly in deep sleep; the liver answers with…
- Hormones: types, receptors and feedbackConcept · Hormones are chemical messages in the blood
- Measuring hormones: stimulation and suppression testsMeasurement · If a hormone is thought to be missing, the gland is stimulated; if it is thought to be in…
- Prolactin and its control by dopamineRegulation · Prolactin makes the breast produce milk
- The adrenal cortex: zones, hormones and androgensConcept · The outer layer of each adrenal gland has three zones: one makes the salt hormone, one the…
- The adrenal medulla and catecholaminesRegulation · The core of each adrenal gland is a nerve relay that pours adrenaline into the blood in seconds…
- The endocrine stress responseRegulation · In injury, surgery or infection, the body releases cortisol, adrenaline and other hormones that…
- The physiological response to hypoglycemiaRegulation · When blood sugar falls, the body first stops insulin, then releases glucagon and adrenaline, and…
- The posterior pituitary: ADH and oxytocinRegulation · The posterior pituitary releases two hypothalamic hormones: ADH, which makes the kidney save…
For completeness
- Bone as a calcium buffer: exchangeable calcium and mineral depositionMechanism · Bone holds a small, quickly available calcium store that steadies blood calcium within minutes…
- Hormone release patterns, clearance and receptor regulationConcept · Hormones come in pulses and daily rhythms, are cleared at set rates, and target cells turn their…
- Phosphate and FGF-23Regulation · Phosphate builds bone and stores energy
- The pineal gland and melatoninRegulation · In darkness the pineal gland releases melatonin, a signal that tells the body it is night
- Thyroid hormone transport and deiodinasesMechanism · Almost all thyroid hormone travels attached to proteins; only a tiny free part works
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Educational physiology content; not a diagnostic or treatment guide and no substitute for a health professional's advice. Values are approximate references. No doses are given.
Representative model, for educational purposes only.