Which of the following is NOT a cause of circus rhythm?
A.damage to the myocardium
B.certain cells coming out of the refractory period too quickly
C.shortened myocardial cells
D.an electrical shock in the middle of a T wave
What type of receptors will bind ATP and adenosine?
A. cotransmitter receptors
B. pyrimenergic receptors.
C. purinergic receptors.
D. None apply.