Respiratory-related discharge of genioglossus muscle motor units.

ABSTRACT:

Rationale

Little is known about the respiratory-related discharge properties of motor units driving any of the eight muscles that control the movement, shape, and stiffness of the mammalian tongue.

Objectives

To characterize the respiratory-related discharge of genioglossus motor units as synaptic drive to the hypoglossal motoneuron pool is increased with hypercapnia.

Measurements

We recorded airflow, genioglossus muscle EMG activity, and the respiratory-related discharge of 30 genioglossus muscle motor units in spontaneously breathing, urethane-anesthetized rats under control conditions and in hypercapnia (inspired CO2: 3, 6, 9, and 12%, 3-5 min at each level).

Main results

All motor units were active throughout all or most of inspiration. Nine of 30 units sho

SUBMITTER: John J 

PROVIDER: S-EPMC2718418 | biostudies-literature | 2005 Nov

REPOSITORIES: biostudies-literature