Endocrine P and T Flashcards
what 4 glands are commonly affected by endocrine diseases
pancreas, thyroid, adrenal, pituitary
describe 3 functions of insulin
promotes cellular uptake and metabolism of glucose, promotes synthesis of glycogen, proteins and fat, involved in cellular ion uptake
why is the species origin of insulin significant?
may be antigenically different to species used in and therefore risk of antibody development.
(porcine identical to canine)
what is the name of the licensed insulin product and what is its conc?
caninsulin, 40IU/ml (most 100)
available as a pen for injection
describe properties of fast acting insulins
short duration of action, IV/IM/SC, used for diabetic ketoacidosis
describe the properties of intermediate insulins
e.g. caninsulin. with zinc salts and given SC
describe the properties of long-acting insulins
e.g. human recombinant. slower onset of action, given SC
how are ‘well’ diabetics treated?
SC intermediate acting. once/twice/day
how are unwell diabetics treated?
may need fast acting in emergency, also CRI and once stable IM injection.
What are the SE’s of insulin? and how are they treated?
hypoglycaemia; confusion, ataxia, seizures, death
treat with oral glucose solutions/ IV dextrose
antibody formation
when are oral hypoglycaemic drugs used? give an example
when owners decline insulin therapy, sulphonylureas
how do sulphonylureas work? SE?
stimuklate insulin production by B cells. (need functioning cells)
SE = V and liver toxicity
what drug is used to treat cows in -ve energy balance/ ketosis?
monensin - intra-ruminal bolus = preventative, an antibiotic which alters flora to allow more efficient fermentation. (increased propionate?)
what are the functions of thyroid hormones?
increase BMR, CNS development, thermoregulation, glycogenolysis, glycolysis, protein metabolism, hair and skin growth. increase HR and contractility
what is the most common thyroid disorder in dogs?
hypothyroidism caused by lymphocytic thyroiditis (immune mediated)
what are the clinical features of hypothyroidism in dogs?
metabolic - lethargy, dullness, obesity, cold intolerance
dermatological - hair loss
how is hypothyroidism treated?
admin L-thyroxine; synthetic analogue of T4. (converted to T3 - active)
given orally once/ twice.
e.g. levothyroxine
thyrotoxicosis is rare
what is the most common endocrine disorder in cats?
hypethyroidism.
mostly cause by benign adenoma of thyroid tissue
what are the consequences of hyperthyroidism?
increased BMR, CO, BP, HR, GI motility and CNS activity
decreased body weight and sleep
how is hyperthyroidism treated?
surgery, low iodine diet, radioactive iodine and anti-thyroid drugs
name 2 anti-thyroid drugs
methimazole and carbimazole
what is the mechanism of action of anti-thyroid drugs?
actively conc in thyroid gland, inhibit thyroid pyroxidase so block incorporation of I into tyrosyl groups and prevent coupling of iodotyrosyl groups to form T3 and T4.
describe 3 preparations of anti-thyroid drugs
slow-release carbimazole (less potent) tablets - converted to methimazole, 1/d.
methimazole tablets - 2 tablets/ d
also transdermal methimazole
describe the pharmacokinetics of anti-thyroid drugs
rapid oral absorption with high bioavailability (increased with food), dosages rate for M (2) and C (1) due to half lives
mainly urinary excretion
don’t split tablets as teratogenic.
