Ichiro Shikata

Acute toluene poisoning during painting

Autopsy findings on a man who fell from a height due to acute toluene poisoning while painting are described. Gas chromatographic examination revealed that the toluene concentrations of his blood, lung, liver and brain were 48, 35, 65 and 80 micrograms/g, respectively. These toluene levels were not enough to be definitely lethal, but were high enough to anesthetize the central nervous system.

Fluidity of Cadaveric Blood After Sudden Death: Part Iii

In rats, fibrinolytic activity and acidosis increased rapidly after death. Postmortem fibrinolysis and the pH, base excess (BE), and [HCO3-] levels were affected by the method of sacrifice: the lower the pH, BE, and [HCO3-] levels, the higher the fibrinolytic activity. Conversely, in experiments using the vascular perfusion technique, low pH, BE, and [HCO3-] levels of the perfusate induced abundant release of plasminogen activator from the vascular wall.

Fluidity of cadaveric blood after sudden death: Part II: Mechanism of release of plasminogen activator from blood vessels

Experiments by the vascular pcrfusion technique in isolated hind leg of the dog showed that after addition of various vasoactive drugs to the perfusate, fibrinolytic activity (plasminogen activator level) of the effluent was elevated. The effects of the drugs were completely inhibited only by the specific blocker of their receptor on the vascular wall. High K+ level of the perfusate also induced abundant release of plasminogen activator from the vascular wall

Cardiac lesions in cases of sudden death in methamphetamine abusers

SummaryA histologic study of hearts was made in nine cases of sudden death (average age 32 years) in methamphetamine abusers. Myocardial hypertrophy and disorganization as well as fibrosis were predominant, and only one case showed coronary atherosclerosis. Since the myocardial changes observed in the present study were similar to those typically seen in hypertrophic cardiomyopathy, it is possible that excess secretion of catecholamines, particularly norepinephrine, induced by methamphetamine abuse is associated in some way with the development of hypertrophic cardiomyopathy.

Potentiation of lethality and increase in body temperature by combined use of d-methamphetamine and morphine in mice

Lethality and change in body temperature in mice were examined after subcutaneous injection of d-methamphetamine and morphine alone or in combination. The LD50 values for methamphetamine and morphine were calculated to be 95 and 670 mg/kg body wt., respectively. When a non-lethal dose of morphine (300 mg/kg) was administered with various doses of methamphetamine, the LD50 for methamphetamine was reduced to 5 mg/kg, indicating a marked potentiation of toxicity by combined use of both drugs. Injection of 5 mg/kg of methamphetamine produced slight hyperthermia, while 300 mg/kg of morphine decreased the body temperature of mice. However, when both drugs were used concomitantly, a marked increase in body temperature was observed. Hyperthermia was also observed when the dose of morphine was reduced to 50 mg/kg. It is postulated that hyperthermia is probably one of the contributory factors in the potentiated toxicity by combined use of morphine and methamphetamine.

Decrease in d-methamphetamine sensitivity in mice due to ethanol: Apparent inhibitory and stimulatory effects of ethanol on d-methampheamine-induced locomotor activity

The locomotor activity of mice was recorded after administration of d-methamphetamine-HCl (1.5, 2.5, 5.0 and 7.5 mg/kg body weight) and/or ethanol (0.8 and 1.6 g/kg body weight). Mice injected with lower doses of d-methamphetamine (1.5 or 2.5 mg/kg) showed a marked increase in locomotor activity, while in those with higher doses of d-methamphetamine (5.0 or 7.5 mg/kg), locomotor activity was not further enhanced, but slightly decreased. Administration of ethanol inhibited the stimulated locomotor activity caused by low doses of d-methamphetamine (1.5 or 2.5 mg/kg), while the stimulation of motility after higher doses of d-methamphetamine (5.0 or 7.5 mg/kg) was potentiated by administering ethanol. Although apparent inhibition and stimulation of d-methamphetamine-induced locomotor activity of mice due to ethanol was observed, it is suggested that mice administered ethanol showed the decreased sensitivity to d-methamphetamine by plotting total locomotor activity of mice against doses of d-methamphetamine administered. The half maximum effective dose of d-methamphetamine for locomotor activity was increased from 1.5 mg/kg to 3.0 mg/kg by concomitant administration of 1.6 g/kg ethanol.

Appearance of formate in blood after ethanol ingestion.

Abstract Human and rabbit bloods after ingestion of ethanol were analyzed for carboxylic acids, and were found to contain not only acetate but also formate. The formate level in the rabbit serum was 0.35μmole/ml at 4 hours after introduction of 10ml of 40% ethanol/kg into the stomach. Administration of [1-14C] ethanol or [2-14C]ethanol resulted in the presence of radioactivity in serum acetate, but not in serum formate. Pretreatment with tryptophan significantly increased serum formate, and pretreatment with folate suppressed the appearance of formate.