SNS antagonists and false transmitters

Question 1

What are the general effects of each adrenergic receptor?

Answer 1

a1- vasoconstriction, relaxation of the GIT
a2- inhibition of NT release, vascular SM dilation
b1- increase force of contraction and heart rate. increase renin release
b2- bronchodilation, hepatic glycogenolysis, relaxation of visceral smooth muscle
b3- lipolysis

Question 2

what are the main three factors that contribute to blood pressure?

Answer 2

plasma volume
cardiac output
vascular tone

Question 3

what is the formula for blood pressure?

Answer 3

BP= CO x TPR

Question 4

what are the effects of beta blockers

Answer 4

reduce heart rate, force of contraction and blood pressure

decreased renin production therefore decrease in ang II

Question 5

give the names of some beta blockers

Answer 5

pindolol
propranolol
timolol
betaxolol

Question 6

what is methyldopa and what does it do?

Answer 6

a compound which can be converted into a false neurotransmitter methylepinephrine in the body which acts on the adrenoceptors. it is not metabolised by MAO so is more likely to accumulate in the post synaptic gap and displace dopamine

Question 7

what are the side effects of methyl dopa

Answer 7

drowsiness, lack of energy, headache

Question 8

which drug is generally used for arrhythmias?

Answer 8

Increased sympathetic drive to heart via b1 receptors Precipitates arrhythmias
propranolol often used

Question 9

what is angina

Answer 9

a type of chest pain caused by reduced blood flow to the heart
stable- fixed narrowing of coronary vessels