The accumulation of 2-aminoisobutyric acid in the costal and lumbar parts of the phrenectomized rat diaphragm in vitro.

The accumulation of 2-aminoisobutyric acid initially increased in denervated costal and lumbar parts of the rat hemidiaphragm after both unilateral and bilateral phrenectomy, followed by a later gradual decrease. The enhancement of accumulation was invariably higher in the costal than in the lumbar part. The accumulation was initially lower in bilaterally than in unilaterally phrenectomized hemidiaphragms, but the relationship was reversed after 72 h due to a faster reattenuation of the enhancements in unilaterally phrenectomized diaphragms.