Antihypertensive Agents (M2) Flashcards
What race has the highest risk of organ damage with high BP?
African Americans
What blood pressure is considered normal? 1. Prehypertension? 2. Hypertension stage one? 3. Hypertension stage two? 4
- 160/100
What are the common etiologies of hypertension?
- renal artery constriction
- coarctation of the aorta
- phenochromocytoma
- Cushing’s disease
- primary aldosteronism
What is the heritability of primary hypertension?
30%
What is the equation to get blood pressure?
(Cardiac output) X (Vascular resistance) = BP
What are the four sites that control BP?
- Kidney
- arterioles
- post capillary venules
- heart
How does the postural baroreflex impact blood pressure?
stretch of vessel walls stimulate carotid baroreceptors, inhibiting sympathetic discharge which increases constriction of arterioles and increases cardiac output
Where is vasopressin produced? 1. Where is it stored? 2
- hypothalamus
2. posterior pituitary gland
What stimulates vasopressin secretion?
- increase in plasma osmolarity
- reduction in extracellular fluid volume
- reduction in BP
What does vasopressin act on?
basolateral membranes of the tubular cell lining in the distal and collecting tubules of the kidneys
What are the actions that vasopressin is responsible for?
- increase water reabsorption
- reduces urinary output
- increases plasma volume
- vasoconstriction on arterioles
What stimulates renin secretion?
- decrease in arterial pressure
2. decrease in quantity of sodium in the body fluids
What is the pathway to the results of the renin-angiotensin system?
- renin splits away angiotensin I
2. angiotensin II causes constriction of peripheral arterioles and causes kidneys to retain water and salt
What are the mechanisms of action for diuretics?
- initially reduce BP by reducing blood volume and cardiac output
- after 6-8 weeks, cardiac output returns to normal while peripheral vascular resistance declines
What is the optimal BP end point?
138/83