Local factors of the cardiovascular regulation

Question 1

what are the 2 principles regarding Regulation of circulation, and the satisfaction of the demand

Answer 1

The demands of material transport to and from tissues
should be met.
● The collapse of normal circulation should be avoided by compensating for the inproportional blood supply to
different organs during different physiological activities.

Question 2

what are the 2 determinants of the intensity of blood flow to certain organs or to a part of that

Answer 2

The local demand on oxygen and on nutrients is the major determinant of the intensity of blood flow to a certain organ or to a part of that.

Question 3

short run: what happens to the tissue?

Answer 3

Tissues adjust their own perfusion by local factors.

Question 4

short run:tone of the vessel in a tissues adjusted by

Answer 4

adjusted by the
intensity of metabolite formation of the tissue.

Question 5

short run: what is autoregulation and myogenic control:

Answer 5

A tissue working at constant metabolic rate needs
constant blood supply. Accordingly transient changes in the mean peripheral arterial blood pressure are counter regulated at the level of the microcirculatory bed.

Question 6

short run: Effects of the endothelium:

Answer 6

The blood pressure mechanically deforms
endothelial cells. This and many plasma factors prompt the endothels to produce humoral signals that influence the contraction state of smooth muscles in the wall of the vessel itself.

Question 7

short run: Effects of the endothelium: 2 major classes of factors:

Answer 7

EDRF (endothel derived relaxing factor)
EDCF (endothel derived contracting factor)

Question 8

short run: Effects of the endothelium: EDRF

Answer 8

The most important component beside other factors is nitric oxide, that is continuously produced by the endothel cells and causes relaxation of smooth muscles

Question 9

short run: Effects of the endothelium: EDCF:

Answer 9

Many factors that cause the contraction of the smooth muscle on the vessels (contraction). The major such signal are the endothelins.

Question 10

short run: Effects of the endothelium: what are the different effects that Acethylcholine have on the diameter

Answer 10

ACh liberated from nerve ending of the smooth muscle causes contraction.

ACh injected into the lumen of the vessel causes vasodilation.

Question 11

short run: Effects of metabolites:

Answer 11

The autoregulative adjustment of the perfusion of a tissue to its metabolic need is based on its oxygen consumption and metabolite production.

Question 12

short run: Effects of metabolites: what is Active hyperaemia

Answer 12

Active hyperaemia changes parallel to the metabolic activity of the tissue. E.g. increased physical activity of muscles.

Question 13

short run: Effects of metabolites: what is Reactive hyperaemia

Answer 13

Reactive hyperaemia is a secondary increase of the perfusion of an organ due to many possible factors.
E.g. inflammation, compression of artery causes hyperaemia after releasing the pressure.

Question 14

long run: what is it

Answer 14

Intensive and sustained work of an organ causes
morphological changes that contribute to the better
perfusion at the local level.