THE EFFECTS OF SOME DRUGS ON THE CROSSED PHRENIC PHENOMENON

Abstract

In cats and rabbits under dial anesthesia, with spinal semisections at C2 and consequent ipsilateral respiratory hemiplegia, crossed respiratory contractions of the paralyzed hemidiaphragm were produced or promoted by prostigmin or eserine, acetylcholine protected by prostig-min, strychnine, section of the vagi after prostigmin, and asphyxia. The data emphasize that differences previously noted between rabbits, cats and dogs, with respect to the crossed phrenic phenomenon, are only quantitative. The most efficient factor for producing crossed contractions is the section of the phrenic nerve.