C H A P T E R 4 3
Drugs affecting blood pressure
663
These drugs are indicated for the treatment of hyper-
tension, alone or in combination with other drugs. They
are also used in conjunction with digoxin and diuret-
ics for the treatment of heart failure and left ventricular
dysfunction. Their therapeutic effect in these cases is
thought to be related to a decrease in cardiac workload
associated with the decrease in peripheral resistance and
blood volume. See Table 43.2 for usual indications for
each of these drugs.
Vasomotor
centre
1
receptors
of heart
Baroreceptors
Sympathetic
ganglia
Adrenergic
nerve
terminals
Angiotensin II
receptor sites
Angiotensin II
receptor sites
ARBs work
here
Adrenal gland
aldosterone
release
Capillary
endothelium
of lungs
Kidney
tubules
Renin
Converting enzyme
Angiotensin II
Angiotensin I
Angiotensinogen
Juxtaglomerular
cells that release renin
α
receptors
of vasculature
Vascular
smooth muscle
Alpha adrenergic
agonist works here
Vasodilators
work here
Diuretics
work here
ACE inhibitors
work here
Beta-blockers
work here
Sympathetic agonist/
vasopressors work here
Renin inhibitors
work here
Ganglion blockers
work here
FIGURE 43.3
Sites of action of antihypertensive drugs.
