Fig. 3. Effect of cog-wheel valve contraction on pulmonary, right ventricular and
systemic blood pressures in an alligator. (A) Pressure in the right ventricle
(RV, red) and pulmonary artery (PA, green) and electrocardiograms (ECGs) from
the centre of the right ventricle (RV ECG, red) and the cog-wheel valve muscle
(cog-wheel ECG, blue) when the cog-wheel valve was functioning. (B) Pressures
in the right ventricle (red) and systemic circulation (right aorta, RAo,
cerise) and ECGs of the same animal with a functioning cog-wheel valve. (C)
Same as A, except that the cog-wheel valve has been inactivated by injection
with acetylcholine.
