Abstract
Adrenal glands of frog were extirpated bilaterally following the Kotsuka's operation. The conduction systems of excitation upon the neuro-muscular junction of adrenalectomised frog were examined with the same method as described previously. Results obtained were as follows:
1) The conduction system were heterodromic or apparently non-conductive. From June to December, heterodromic system was dominant. On the other hand, from January to May apparently non-conducting system was relatively dominant.
2) After a certain period following the adrenalectomy the isodromical conduction system could not be found.
3) The conduction systems of adrenalectomised frog could be turned into the isodromical conduction system under certain condition e. g. administration of adrenaline.
