Treatment of hypertension

Question 1

Short term regulation of bp?

Answer 1

• Baroreceptors

*Sympathetic/ parasympathetic outflow

Question 2

Equation for mean arterial blood pressure

Answer 2

MABP= CO X TPR

Question 3

Long term regulation of bp

Answer 3

• Hormonal control of total
  body sodium:
  Control of blood volume,
  via ECFV
• Degree of
  vasoconstriction

Question 4

Hypetension defined as?

Answer 4

bigger or equal to 140/90mHg

Question 5

What are the two types of hypertension?

Answer 5

Secondary( identifiable cause) (<10%)
* Renal disease
* Vascular – e.g., renal artery stenosis
* Hormonal – e.g., Conn’s syndrome, Cushing’s
syndrome
* Monogenic genetic diseases – e.g., Liddle’s

Primary or essential (>90%)
* Genetic predisposition

Question 6

For which conditions is hypertension a risk factor/

Answer 6

• Stroke, Ischemic heart disease
• Left ventricular hypertrophy, heart failure
• Renal failure
• Retinopathy

Question 7

How do ACE inhibitors work?

Answer 7

Inhibiting enzynme that activates angiotensin I to angiotensin II

Angiotensin II causes vasoconstriction and promotes aldosterone secretion ( increases bp via sodium retention )

Question 8

How do diuretics work?

Answer 8

• Increase in sodium and
  water excretion
• Reduce blood volume →
  reduces CO → reduce BP
  (BP ≈ CO x TPR)

Question 9

How can hypertension be treated considering sympathetic neural effects on CVS

Answer 9

Beta blockers (β1
blockers, e.g. atenolol):
reduction in CO and
renin release

• β1 – increase HR and
  contractility →
  increase CO →
  increase BP

Question 10

Why do K channel openers decrease bp?

Answer 10

• Increased outward K flow causes
  Hyperpolarization
• This causes reduced VGCC activity
  So Reduced calcium therefore
• Less MLCK activity
  Increased relaxation
  (vasodilatation)

Question 11

How do Voltage-dependent
Ca2+ channel blockers reduce bp?

Answer 11

• Block VGCC activity in
  vascular smooth muscle cell
• Reduced [Ca]i
• Less MLCK activity
  Increased relaxation
  (vasodilatation)

Question 12

Treatment pathways for hypertension?

Answer 12

• Non-pharmacological: life-style modifications
• Pharmacological treatment
• Surgical (if known cause, e.g. Conn’s syndrome)

Question 13

Lifestyle modifications

Answer 13

• Quit smoking
• Weight control
• Eat less salt
• Regular exercise
• Reduce alcohol intake

Question 14

Major Classes of Anti-hypertensive Drugs?

Answer 14

• ACE inhibitors
• Angiotensin II receptor blockers
• Diuretics
• Drugs acting on Sympathetic Nervous System
• Vasodilators