endocrine system presentation
TRANSCRIPT
The Endocrine
System
…….hormonal control of homeostasis
Compare Nervous /hormonal
Functions of Endocrine System
Mechanism of action
The Major Endocrine Glands
Pineal Body
Pituitary
Thyroid ParathyroidsThymus
Adrenals Pancreas
Testes Ovaries
Thyrotrophin (the Thyroid Stimulating Hormone -TSH) Regulates the activity of the thyroid gland
Adrenocorticotrophin (ACTH) Regulates the function of the adrenal cortex of the
adrenal glands
Gonadotrophins a) Follicle Stimulating Hormone (FSH)b) Lutenising Hormone (LH) Regulate the reproductive organs
(gonads)
FSH ♀ regulates the development of ovarian
follicles and secretion of oestrogen
FSH ♂ regulates the
production of sperm in men
The Anterior Pituitary –Trophic Hormones
LH ♀ stimulates ovulation and formation of the
corpus luteum that secretes oestrogen and progesterone.
LH ♂ Stimulates
testosterone secretion in the male
Melanocyte Stimulating Hormone (MSH) Stimulates the production and release of melanin
by melanocytes in skin (basal layer).HYPERSECRETION - unnaturally dark skinHYPOSECRETION - prone to sunburn
The Anterior Pituitary –Other Hormones
Prolactin Enlarges the mammary glands and stimulates milk
production HYPERSECRETION - over production of milk and
enlargement of breasts (also occurs in men) HYPOSECRETION - under production or no
production of milk
Human Growth Hormone (HGH) Regulates growth during pregnancy. HYPERSECRETION causes gigantismHYPOSECRETION causes dwarfism
The Posterior Pituitary Hormones
VasopressinAnti Diuretic Hormone (ADH)
Regulates the body fluidsHYPERSECRETION - high blood pressureHYPOSECRETION- low blood pressure
Oxytocin Regulates the release of milk in
lactating women Induces uterine contractions in
labour Has a role in orgasm and inducing
'pair bonding'…ie. Love!)
The Thyroid Hormones Thyroxine
Increases the metabolic rate HYPERSECRETION -
Hyperthyroidism - HYPOSECRETION -
Hypothyroidism
Calcitonin Lowers blood calcium and
phosphorus levels maintains dense bones by
inhibiting osteoclast activity.
HYPERSECRETION - leads to low blood calcium levels
Thyronine Reduces the metabolic rate
Parathormone Increases blood calcium and phosphorus
levels by stimulating osteoclast activity, enhancing calcium reabsorption (kidneys) and enhances absorption of calcium in the intestines
HYPERSECRETION - Softened bones from lack of calcium
HYPOSECRETION - Low blood calcium levels
The Parathyroid Hormones
Insulin Lowers blood glucose levels by
increasing glucose transport into the body cells and increasing glycogen synthesis in liver and muscle cells
HYPERSECRETION - HypoglycaemiaHYPOSSECRETION - Hyperglycaemia • low levels of insulin leads to diabetes
mellitus type 2 (NIDDM), no insulin leads to diabetes mellitus type 1 (IDDM)
The Pancreatic Hormones
Glucagon Raises blood glucose levels by
inhibiting glucose uptake and liberating glucose stored as glycogen.
The Thymus Hormones
Thymic Factor (TF) & Thymic humoral factor (THF) Involved in the activation of T lymphocytes (T-
cells)HYPOSECRETION - increased susceptibility to disease
Adrenal Cortex
Aldosterone Increase reabsorption of mineral salts (sodium
etc) in the renal tubules
HYPOSECRETION - Addison's Syndrome (dehydration, weight loss, hypoglycaemia, hypotension)
The Adrenal Hormones
Adrenal Medulla
Adrenaline (aka epinephrine or nor-adrenaline)
Affects the heart; breathing centre of brain; arterioles of skin and digestive tract; muscles of the gut, muscles of the body, liver.
Secreted during fear, fight, flight response to danger
HYPERSECRETION - stress / anxiety disorders, digestive disorders, CV disorders, skin disorders, immune weakening etc
The Pineal Hormones
Seratonin Regulates Mood, sexuality and body
rhythms (responds to sunlight)HYPERSECRETION - ecstasyHYPOSECRETION - depression,
Seasonal Affective Disorder (SAD)
Melatonin Regulates sleep/wake or circadian
rhythms Stimulated by darkness and inhibited
by light
The GonadsTestes
Testosterone Regulates the production and
maturation of sperm; Responsible for the secondary
male sexual characteristics
Ovaries
Progesterone
Prepares the endometrium for implantation and pregnancy
Oestrogen Matures the ovum for release; Responsible for the secondary
female characteristics