Abstract
The pathogenesis of achalasia has not yet been entirely clarified. Several investigators have reported data suggesting certain lesions in the central nervous system in association with achalasia. The present study was undertaken in attempt to find relationship between the central nervous system and the esophageal movement.
One or two stimulating electrodes were implanted in and around the ventromedial nucleus of the hypothalamus in 22 adult cats. Eight cats died shortly after implantation. In the remaining 14 cats with 25 electrodes, simultaneous recordings of intraluminal pressure and elctromyogram were carried out at three different levels of the esophagus upon electrical stimulation of the hypothalamus in the unrestrained and unanesthetized condition. The position of electrode tip was identified with serial sections after completion of each experiment. The responses were classi fied into (1) (+) when contractions were observed in the intraluminal pressure tracing and electromyogram either simultaneously or in an orderly fashion at these three levels of the esophagus, which occurred with 3 electrodes; (2) (±) when the responses were equivocal, which occurred with 4 electrodes; and (3) (-) when no responses were observed, which occurred with 18 electrodes.
The tips of the three electrodes showing the (+) response were found to be in the center, the inferiomedial portion, and the inferior portion of the ventromedial nucleus of the hoypthalamus respectively. The tips of the electrodes which did not show the (+) response were not located within this nucleus.±These results indicate that the ventromedial nucleus of the hypothalamus is one of the centers for the esophageal movement.
