Aromatic nitro- and amino-compounds have been long known as the blood poison, but it was 13roved from author's experiments on the red blood cells in rabbits that there are fairly more differences among these compound. After nitrobenzene methemoglobin and Heinz's body was present, while was absent after aniline, nitrobenzene and aminophenol of the same or rather more amount. The reduction-potential of some m-nitroaniline derivatives was measured by means of polarography, where it was found that the lower the potential, the more toxic would be for the red blood cells.
It was proved from author's experiment on the liver perfusion in rabbits that the detoxicating processes for the methemoglobin formation induced by o-aminophenol would be taken place in the liver, in which no methemoglobin is formed except when the blood vessels running into liver are ligated, whereby being given even only small amount of the drug,
Synergism of physostigmin with acetylcholin, though it might be ascribed to anticholinesterase action of the former, was pursuited with the heart of Bufo vulgaris japonicus. The administration of physostigmin, as compared with no administration of the drug, resulted in the appearance of the more remarkable cardio-inhibitory effect upon the in vivo self-blood-circulating heart and the iso-lated or the in vivo heart, both being perfused, whose vagus or sympathetic nervous fibres were suffering the electric stimulus. There were seasonal variations in the degree of this action, strong in winter and weak in spring or fall. Physostigmin may possibly promotes excitability of cardio-sympathetic nervous endings, though not so distinct in cardio-sympathetic nervous endings as in vagus, but appreciated by the increased heart beats produced by the electric stimulus to sympathetic or vagosympathetic nerves while the drug be acting. This promotion of heart beats by physostigmin was subjected to seasonal variations and most sinificant in spring or summer. Physostigmin, when given to the heart perfused by. fresh Ringer's solution for a long time, brought about the remarkable Increase of heart beats which was not observed before perfusion. This may be possibly attributable to the excitement of sympathetic nervous endings by physostigmin.
The rate of oxidation of alcohol in the tissues of rabbits (liver, brain, heart, kidneys and muscles) was determined. by the manometrical method as previously reported by the author. The concentration of alcohol added in tissue hemogenates was 0.4 %. The data indicated that the oxidation rates in the liver, brain and heart increase by 18%, 43% and 94% respectively after habituation. Discussing this data and the results described in literatures, the author concluded as follows : The activity of the enzyme system in brain appears to increase after habituation, without being inhibited by alcohol in higher concentration. It is, therefore, probable that the central nervous system of the habituated animals can oxidize more alcohol than that of the non-habituated and in addition utilize it as a energy source of cerebral activity.
The isolated bullfrog's heart was perfused with heparinized blood and then its O2-uptake, CO2-production, cardiac output, venous and aortic pressure, and EKG were able to be measured simultaneously by our apparatus, which was described in detalis.
The paralyzing action of salicylamide was more precisely investigated in mice and rabbits. The drug possessed a remarkable antagonistic action to the convulsive and lethal effects of strychnine and this action was apparently stronger than that of myanesin in comparison with their toxicities. The antagonistic action of salicylamide against metrazol and picrotoxin, however, was as weak as myanesin. In small doses salicylamide and myanesin had a marked depressant action on the flexor reflex of cats while the normal knee jerk was not affected. Again, at about the same doses of the drugs the multisynaptic reflex discharges were reduced without remarkable effect on the monosynaptic ones in lightly anesthetized or spinal cats. The results indicate that salicylamide as well as myanesin has a selective depressant action on the interneurons of the spinal cord. Only because of the other results, it may be supposed that the higher levels in central nervous systems should be more vulnerable to salicylamide than myanesin.
In this report the paralyzing and antistrychnine activities of salicylamide derivatives were comparatively examined in mice and rabbits. Aromatic acid amides with an alkoxy group in the ortho position possessed the strongest activities. Methyl or dimethyl substitution on the N atom in the acid amide group destroyed the potency. From the results, it may be concluded that the presence of a hydroxy or alkoxy group in the ortho position as well as a free acid amide group seems to play an important role so that salicylamide derivatives may possess above described activities.
Radioactive phosphate (P32) was used to study influence of urethane on the P metabolism of rat's brain. The amounts of inorganic P in blood plasma and total, acid-soluble and residual P in the brain of rat under urethane anesthesia were determined, and the uptake of P32 by these fractions was measured at 3rd, 5th and 24th hrs after the intraperitoneal injection of the tracer by Geiger counter (Nuclear Model 166). The results were compared with controls (without urethane). (1) Inorgonic P in the plasma was increased under urethane anesthesia. (2) In anesthetized rats the specific activity (SA) of acid-soluble P increased at 3rd hrs, and that of residual P decreased at 5th and 24th hrs. (3) The SA of total P and acid-soluble organic P to that of inorganic P were not influenced significantly by urethane.
A leucopenia is usually induced in a maximal extent after a single subcutaneous dosis of 25.0 mg/kg of Nitromin (methyl-bis-β-chloroethylamine-N-oxide HCl) in male rats weighing 150-250 g in body weight which would return to normal in 7-10 days. The rate of recovery to normal begins to be delayed at the third injection of repeated dose if applied every tenth day. The therapeutic effect of some compounds for the experimental leucopenia was studied where those compounds had been given 15 minutes prior to Nitromin injection and the shift of leucocyte : count was observed every twelfth hour thereafter. Among those compounds L-cystein HCl in a dosis of 500 mg/kg and Platonin, a photo-sensitive agent, in 50γ/kg were found well to prevent the leucopenia induced after Nitromin in 25.0 mg/kg.