Abstract
In an attempt to investigate the influences of the injection of blood-Ringer's solution saturated with carbon dioxide on the living subjects, the author observed its toxicity to mice, its influences on the blood pressure, respiration and the amount of serum Ca and serum Cl of the rabbits. Further, in order to elucidate the relationship between carbon dioxide and poisons to the autonomic nerve system, the changes seen in the influences of carbon dioxide on the serum Ca by the combined injection with the poisons to the auto-nomic nerve system were observed.
First of all, blood-Ringer's solution saturated with carbon dioxide was administered to the rabbits intravenously. However, almost no recognizable findings were noted in the observation of the living subjects. A single case of the rabbit demonstrated a slight edema and change of the colouring in the ear lobe where the agent was injected. The temperature of the rabbit seemed almost not to be affected by the injection. When the blood-Ringer's solution saturated with carbon dioxide was injected subcutaneously or intraperitoneally into mice, almost no remarkable changes were observed within 24 hours ; and there were only very few fatal cases. In order to trace the changes in the amount of carbon dioxide contained in the blood induced by the injection of blood-Ringer's solution saturated withh carbon dioxide, the following experiments were performed; i. e., the amount of carbon dioxide was estimated in the cases when blood-Ringer's solution saturated with carbon dioxide alone was injected intravenously into the ear vein, when the same solution was injected into the same vein under urethane anaesthesia and when the same solution was injected in the jugular vein under urethane anaesthesia. The results of the above experiments showed that the carbon dioxide content in the blood recovers approximately the normal level after the elapse of 5 hours in all cases, and that the vol.% of the carbon dioxide content in the blood was higher in all cases 15-75 minutes after the injection. As regards the blood pressure and respiration of the rabbits, observations were simultaneously made as to how the influences of adrenaline or acetylcholine on the rabbits are affected by carbon dioxide in the case with the blood-Ringer's solution alone, in the cases with blood-Ringer's solution combined with adrenaline or acetylcholine. When the blood-Ringer's solution saturated with carbon dioxide was injected under urethane anaesthesia, the blood pressure was found lower by 30-40 mm Hg in the first place, and it reached the lowest pressure after 1 minute. However, it recovered approximately the normal pressure after 5 minutes. The respiration rate was also found reduced, but the amplitude became larger. However, they came back to the normal as the time elapsed. The blood pressure raising action of adrenaline and blood pressure lowering action of acetylcholine were found, almost not affected by the combination with the bloon-Ringer's solution saturated with carbon dioxide suggesting that carbon dioxide does not essentially affect the action of both of the above chemicals. Following the above, experiments were performed to investigate as to how the serum Ca is affected by the injection of the blood-Ringer's solution saturated with carbon dioxide. When the solution alone was intravenously injected, almost no change was noted in the serum Ca during the period of 24 hours from the injection. When the solution was applied in combination with adrenaline or with pilocarpine, it was learnt that the slight serum Ca reducing action of adrenaline and serum Ca increasing action of 'pilocarpine are not affected by the injection of the solution in general. Contrary to this, it seemed that the injection of the blood-Ringer's solution saturated with carbon dioxide induces the increase in the serum Cl 15 and 75 minutes after the injection, and the serum Cl recovers the normal value after 24 hours.
