The glycogen content in both livers and muscles as well as the blood sugar values were measured after letting guinea pigs standing for 2 hours at room temperature or at 41°C. after imposition of a definite dose of insulin, Thyradin, adrenalin, pilocarpine and atropine and in some cases together with vitamin C, and the following results were obtained: 1. Though liver glycogen always decreased by imposing these drugs, the action of pilocarpine seemed to be weaker than Thyradin, and the ones of insulin, adrenalin and atropine were most apparent in a similar degree. 2. Liver glycogen content decreased further by exposing the animals to high temperature after imposing these drugs, but the degree, from the viewpoint of the decrease caused by drug itself, was not so different among these drugs except insulin, which introduced an apparent decrease, and agreed well with the degree of the cases exposed to high temperature without imposition of these drugs. 3. The decrease of liver glycogen content of the animals exposed to high temperature after imposition of these drugs was inhibited by simultaneous imposition of vitamin C, and the inhibition was predominant over the decrease owed to insulin or atropine. 4. Muscle glycogen content decreased slightly by adrenalin and apparently by atropine, and the other drugs seemed to have no obvious action. 5. Muscle glycogen content decreased more or less in all cases by being exposed to kigh temperature after imposition of the drugs, and the degree, from the viewpoint of the decrease caused by drug itself, was higher in adrenalin and pilocarpine cases than in insulin and Thyradin cases, and the one of an atropine case was far low agreeing with the case exposed to high temperature without imposition of the drug. 6. The decrease of muscle glycogen content under high temperature after imposition of these drugs was more or less inhibited by simultaneous imposition of vitamin C, but these effects appeared hardly on insulin and pilocarpine cases, while the action of vitamin C was predominant over the action of atropine. 7. Though blood collection made the blood sugar values increase, the values in all cases except atropine imposition, which made the value much more increase than the non-imposed, grew lower than the one before collection, and the degree was most obvious to insulin case. 8. The blood sugar values under high temperature after imposition of these drugs decreased further in insulin, Thyradin and pilocarpine cases, while increased in an adrenalin case and the increase in an atropine case was accelerated. 9. By further imposition of vitamin C on the above mentioned cases, the blood sugar values were influenced by vitamin C in a way to inhibit both the decrease in a Thyradin case and the increase in atropine and adrenalin caes, but no influence was proved in insulin and pilocarpine cases.