hormones 25 Flashcards
What are the two chemical classes of hormones?
Lipid soluble - hydrophobic
or water soluble - hydrophilic
What kind of hormones are lipid soluble?
Steroids eg testosterone, oestrogens, thyroid hormones and nitric oxide.
what kind of hormones are water soluble?
Amines, peptides, proteins, eicosanoids.
prostaglandins and leukotrienes, act locally as hormones in most tissues of body so little found in blood.
They are released by virtually all cells.
are hormones slower or faster than nerve responses?
Slower.
Describe prostaglandins.
Smooth muscle, blood flow, promote fever, intensify pain etc.
Describe leukotrienes.
Stimulate WBC movement and mediate inflammation.
What is the relationship between aspirin and ibuprofen and prostaglandin and leukotriene synthesis?
Aspirin & ibuprofen inhibit prostaglandin synthesis but don’t affect leukotriene synthesis.
What type of soluble hormone produces a second messenger called ‘Cyclic AMP’?
Water soluble hormone (hydrophilic)
How are hormones secreted?
In short bursts.
What are the secretion of hormones controlled by?
Negative feedback.
How are hormone secretions regulated?
Signals from nervous system,
chemical changes in blood,
other hormones.
Name some endocrine disorders.
Acromegaly - excessive GH in adults.
pituitary dwarfism - low levels of GH in children.
pituitary giantism - excessive GH levels in children.
Diabetes - insufficient insulin, type 1& 2.
Goitre - insufficient iodine, excessive thyroxine.
Hyperthyroidism - (graves disease) excessive thyroxine - goitre.
Hyperthyroidism - (myxoedema) insufficient thyroxine.