McKenna's Pharmacology for Nursing, 2e

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C H A P T E R 4 3 Drugs affecting blood pressure

Vasomotor centre

Ganglion blockers work here

1 receptors of heart Baroreceptors

Beta-blockers work here

Sympathetic agonist/ vasopressors work here

Sympathetic ganglia

Alpha adrenergic agonist works here

Adrenergic nerve terminals

α receptors of vasculature

Vasodilators work here

Vascular smooth muscle

Angiotensin II receptor sites

ARBs work here

Diuretics work here

Kidney tubules

Adrenal gland aldosterone release

Angiotensin II receptor sites

Capillary endothelium of lungs

Juxtaglomerular cells that release renin

Renin inhibitors work here

Converting enzyme

Renin

Angiotensin II

Angiotensin I

Angiotensinogen

ACE inhibitors work here

FIGURE 43.3  Sites of action of antihypertensive drugs.

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.