Positive and Negative Inotropic Factors Flashcards
1
Q
What does positive inotropic mean?
A
- increases strength of contraction of cardiac muscle
2
Q
What 4 factors lead to positive inotropic effects?
A
- increased temp
- B andrenergic stimulation
- extracellular Ca2+
- peptides
3
Q
What does increased temp cause
A
- Q10 increases rxn rates
4
Q
What does B andrenergic stimulation include?
A
- adrenaline
5
Q
What does extracellular Ca2+ do?
A
- present in cytosol of muscle that causes contraction
6
Q
What 5 peptide hormones cause positive inotropic effects?
A
- arginine
- vasotocin
- oxytocin
- adenosine
- histamine
7
Q
What does negative inotropic mean?
A
- decrease in strength of contraction
8
Q
What 5 factors lead to negative inotropic effects?
A
- hypoxia
- acidosis
- a-adrenergic stimulation (some species)
- extracellular Ca2+
- Acetylcholine (vagus nerve)
9
Q
Why is Hypoxia a negative factor?
A
- cardiac myocytes are very aerobic
10
Q
What is acidosis?
A
- strenuous exercise
11
Q
What does acetylcholine activate?
A
- parasympathetic NS (rest/digest)
12
Q
A
