Segmental motor innervation of the cat diaphragm.

In ten anaesthetized adult cats, bipolar recording electrodes were inserted in different muscular bundles of each hemi-diaphragm. Both stimulation and section of the phrenic cervical branches were made. The upper phrenic cervical branch innervates both the sternal and lateral portions of the diaphragm whereas the lower phrenic cervical branch innervates both the lateral and dorso-caudal portions.