SummaryThe possible effects of ACTH on renal tubular capacity to reabsorb glucose have been investigated in 11 patients. There is no reason to think that ACTH modifies the capacity of the renal tubes to reabsorb glucose, or the blood level at which glucose appears in the urine, as J.-W. Conn and collaborators affirmed.In eight of the eleven patients, TmG was measured before the intravenous injection of 25 mgr of«Cortrophin»Organon and from two to four hours after the injection of hormone. The three other patients wore studied before ACTH administration and at the third day of a treatment for rheumatoid arthritis, when 100 to 120 mgr of ACTH were given I. M. No significant change of TmG was noted. No change of the appearance threshold was noticed in the six patients whose threshold values were especially studied.These observations do not agree with the conclusions of J.-W. Conn and collaborators who thought that ACTH decreased the renal threshold for glucose and induced renal glucosuria on the first day of his administration. It is the feeling of the authors that Conn’s conclusions were to hative as he did not use the usual technics of kidney function exploration : i. e. determination of the glomerular filtration rate, and of TmG.It would seem possible to object to our work that the dosage of ACTH used was not sufficient to observe the effects on glucose renal threshold. However it must be noticed that the dosage used was sufficient to decrease the number of blood eosinophils in all cases and to increase the fasting blood sugar level in patients treated for rheumatoid arthritis.At last it will be noticed that the Organon product has a higher biological activity than the ACTH compound generally used by American workers.