Rat Blood Pressure

Adrenaline is found in the adrenal medulla (produced from noradrenaline by phenyl-ethanolamine-N-methyl transferase). Heart rate and force are increased through beta₁ -adrenoceptors (G-protein coupled to adenylate cyclase). At low doses beta₂ -adrenoceptors dilate resistance vessels in e.g. muscle and reduce total peripheral resistance (TPR); diastolic pressure falls therefore. At higher doses alpha₁ -adrenoceptors in e.g. skin and gut cause constriction of vessels which increases TPR and systolic pressure is increased.

	True	False
Is an effective agonist at all types of adrenoreceptors.
Increases heart rate at all doses above threshold.
Increases pulse pressure at all doses above threshold.
Occurs in sympathetic nerve terminals
Increases systolic blood pressure at all doses above threshold.

Rat Blood Pressure DEMO