Pharmacology Lecture 16: Blood Pressure Drugs Part 1

What are the four factors that determine blood pressure?

1. Heart rate

2. Peripheral vascular resistance

3. Systolic volume

4. Blood viscosity

What is the term for the amount of blood pumped by the heart per minute?

Cardiac output

What is the term for the sum of the forces exerted by peripheral vessels that the left ventricle must overcome to eject blood?

Peripheral vascular resistance

How can you calculate blood pressure?

Cardiac Output x Peripheral Vascular Resistance

How can you calculate cardiac output?

Systolic Volume x Heart Rate

What are the two ways the cardiovascular system compensates for increased blood pressure?

1. Vasodilation

2. Decrease cardiac output

What is the way the renal system compensates for increased blood pressure?

Excretion of fluid

What does excretion of fluid decrease for blood?

Volume

What is the blood pressure for hypertension stage 1?

130 - 139 / 80 - 89

What is the preferred first-line agents for treating hypertension?

ACE inhibitors

What are the two main ACE inhibitors?

1. Lisinopril

2. Enalapril

What is the normal function of ACE?

Cleave angiotensin I to form angiotensin II

How does ACE affect vessels?

Vasoconstriction

What is diminished by ACE inhibitors?

Bradykinin inactivation

Are ACE inhibitors a vasoconstrictor or vasodilator?

Vasodilator

What two secondary messengers that respond to angiotensin II in vascular smooth muscle?

1. IP3

2. DAG

What is the effect of IP3?

Mobilize intracellular Ca

What is the effect of DAG?

Activate protein kinase C

What secretion is reduced by ACE inhibitors?

Aldosterone

What rate is decreased by the reduction of aldosterone?

Water/Sodium retention

What is the main idea of using ACE inhibitors to reduce blood pressure?

Decrease peripheral vascular resistance without affecting cardiac output

What are the three adverse effects of lisinopril?

1. Orthostatic hypotension

2. Xerostomia

3. Fetal morbidity

What are the two main angiotensin receptor blockers?

1. Losartan

2. Valsartan

What is blocked by angiotensin receptor blockers?

Vasoconstricting/Aldosterone secreting effects of angiotensin II

What are two effects in vessels are decreased with angiotensin receptor blockers?

1. Vasoconstriction

2. Peripheral vascular resistance

What are the two adverse effects of losartan?

1. Orthostatic hypotension

2. Dizziness

What is the direct acting vasodilator of arterioles that has little on veins?

Hydralazine

What is the adverse effect of hydralazine?

Orthostatic hypotension

What is the centrally acting adrenergic drug that acts asa alpha 2 adrenergic agonist?

Guanfacine

What is diminished by guanfacine?

Central adrenergic outflow

What two rates are decreased by guanfacine to reduce blood pressure?

1. Vasomotor tone

2. Heart rate

What are the two main adverse effects of guanfacine?

1. Dizziness

2. Dry mouth