[Characteristics of the afferent activity of the cardiac nerves of Agrionemys horsfieldi turtles].

On the basis of changes in afferent impulsation emerging from the heart of the tortoise A. horsfieldi under various conditions of cardiac haemodynamics, it was shown that bursting activity of the superior cardiac nerves belongs to mechanoreceptors which are located in the ventricle and the adjacent arterial vessels. The discharge in these mechano-receptors coincides with ventricular systole. The second, predominant, type of afferentation is presented by irregular continued activity in both the superior and inferior vagal branches. The origin of this activity remains uncertain.