Dr. Zachow - MI

Question 1

Where are the two chemoreceptors located?

Answer 1

Peripheral is located in the carotid and aortic bodies

Central is located in the medulla

Question 2

Which afferents are responsible for bringing back baroreceptors and chemoreceptors information to the CNS?

Answer 2

9 and 10

Question 3

1) What does arginine vasopressin/ADH/vasopressin do?
2) angiotensin
3) aldosterone

Answer 3

1) vasoconstricter that helps you maintain water in your body to increase BP.
2 and 3) involved in the RAAS system. They are vasoconstricters that help maintain salt as well as fluid retention (they go together).

Question 4

What is the main contributor of systolic BP? diastolic BP?

Answer 4

Systolic - cardiac output - vasoconstricted

Diastolic - vascular resistance - vasodilated

Question 5

What factors determine total peripheral resistance?

Answer 5

Diameter of the arterial tree, VSM function, alpha1 from epi and norepi, vasopressin, angiotensin, aldosterone.

Question 6

Normal BPs above and below age 60

Answer 6

Above –> less then 150/90

Below –> less than 140/90

Question 7

Difference between ischemia and infarction

Answer 7

Ischemia is when there is reduced blood flow to the heart.

Infarction is when ischemia leads to necrosis in the heart.

Question 8

The integrated Pressure-volume regulatory system
- sensory
- afferents
Etc.

Answer 8

sensory - P: bara and chemo C: - chemo and osmo
Afferents - 9 and 10
Central integration - at the medulla for chemoreceptors and at the hypothalamus for osmoreceptors
–> message gets sent to effectors –> the effectors respond with various physiological changes –> then there is a feedback mechanism to see if these changes need to continue or not

Question 9

What are the two ways that the left ventricle can grow?

Answer 9

Concentric - layer the sarcomeres on top of each other so the wall gets thicker
Eccentric - layer the sarcomeres next to each other so that the wall gets longer

Question 10

Talk about remodeling

Answer 10

There is negative remodeling and non-negative remodeling. In negative remodeling, which is due to chronic pressure/volume overload, we can see sarcomere proliferation that can lead to fibrosis, endothelial dysfunction, and apoptosis. We can also see it affect the RAAS pathway as well as alter various genes.
On the contrary, remodeling due to excessive exercise is not bad for you and does not involve the RAAS system.