Primary Vs. Secondary Hypertension

Question 1

Obesity and Hypertension
- relation and why obesity increases likelihood of hypertension

Answer 1

1. Increased reabsorption of sodium and water
   A) compression of the kidney by visceral fat
   B) activation of RAAS
   C) activation of aldosterone-independent mineralcorticoid receptors
2. Increased activation of sympathetic nervous system and inflammation
   A) abnormal secretion of lepton from adipose tissue
   B) via RAAS, insulinemia, and baroreceptors dysfunction

Question 2

Role of the Kidney in Hypertension

Answer 2

Production of renin

Resetting the BP diuresis/natriuresis curves

Modulation of sympathetic nervous system

Site of immune activation with release of vasoactive cytokines

Question 3

Angiotensin II at cellular level (pathway)

Answer 3

Angiotensinogen to Ang I via renin —> Ang I to Ang II via ACE

Ang II binds AT1R causing:
1) increased cytosolic calcium —> MLCK activation and muscle contraction
2) increase p38

AT1R causes NAD(PH) to increase ROS which causes NF-kB to activate genes responsible for hypertrophy, proliferation, hyper contractility, and remodelling

AT1R also causes EGFR activation —> MAPK activation

Question 4

Vascular Remodelling
1) Large Arteries
2) Small Arteries (200-300um)
3) Arterioles

Answer 4

1) outward hypertrophy
2) inward hypertrophy
3) inward, eutrophic remodelling and rarefaction

Question 5

Link of Hypertension to Atherosclerosis

Answer 5

Hypertension increases risk of atherosclerosis occuring

Question 6

Secondary Hypertension
- causes

Answer 6

ABCDE
A - Accuracy
A - Sleep Apnea
A - Primary aldosteronism (via suprarenal cortical tumour)
B - Bruits (renovascular hypertension or Renal Artery stenosis (narrowing of renal artery increasing turbulence and causing bruit)
B - Bad kidneys (chronic kidney disease)
C - catecholamines (pheochromcytoma)
C - Coarctation of the Aorta
C - Cushing’s Syndrome
D - Diet
D - Drugs (prescription, and illicit)
E - Erythropoietin
E - Endocrine (thyroid and Parathyroid)

Question 7

Pheochromcytoma and how it causes hypertension
Clinical features

Answer 7

Is a Chromaffin cell tumour secretion excessive amounts of catecholamines

Causes release of increased amounts of catecholamines (E and NE, or increased dopamine secretion if malignant) causing vasoconstriction and increased peripheral resistance and BP (may be episodic or sustained)

Clinical features:
Headache
Sweating and flushing
Anxiety
Nausea
Palpitations/chest pain
Weakness
Epigastric pain
Tremor

90% of patients have headaches, palpitations and sweating alone, or in combination

Question 8

Cushing’s syndrome
What causes it?
Symptoms

Answer 8

Caused by a basophil adenoma, overactive pituitary or chromophobe adenoma —> all causing increased ACTH release resulting in overactive adrenal cortex
Can also be caused by hyperplasia of adrenal cortex or adenoma of adrenal cortex or carcinoma of adrenal cortex

All produce excess cortisol which causes the below symptoms
Red cheeks
Moon face
Fat pads on back (buffalo hump)
Thick skin
Bruisability ecchymoses
Red striae on skin
Thin arm and legs
Pendulous abdomen
Poor wound healing
Osteoporosis, compressed vertebrae

Question 9

How does Erythropoietin cause Hypertension

Answer 9

Increases blood viscosity and therefore an increase in blood pressure

Question 10

Hypertensive Heart disease

Answer 10

Causes concentric left ventricular hypertrophy due to pressure overload