In class, we discussed an experiment in which 2 frog hearts…

In class, we discussed an experiment in which 2 frog hearts were placed in different beakers of salt solution.  The beakers were connected by tubing that allowed the movement of the salt solution.  Heart 1 had a vagus nerve still attached, heart 2 did not have the attached vagus nerve.  The change in the contraction of heart 2 was due to