METABOLIC PROPERTIES OF CEREBRAL TISSUES OF GUINEA PIGS WITH CHRONIC METHAMPHETAMINE INTOXICATION

POTASSIUM EFFECT AND GLYCOLYSIS-INHIBITING FACTOR IN SERUM

Abstract

Previously Utena and Ezoe investigated the in vitro metabolism of the cerebral tissues taken from chronic schizophrenics and methamphetamine addicts at the time of frontal leucotomy. They found, in both cases, a significant decrease in aerobic lactate formation despite normal oxygen uptake. Further, they reduplicated this abnormal type of tissue metabolism in guinea pigs in which chronic methamphetamine intoxication was experimentally produced.
As the incubation medium adopted by these authors was devoid of Ca, it was required to examine their results both in the ordinary medium containing Ca : and that with high potassium concentration (Potassium effect).
Moreover, it was asked whether any abnormalities were found in other organs than the brain of the intoxicated animals especially in the endocrine system and in the body fluids.
In the present studies, chronic methamphetamie intoxication was produced in guinea pigs and the investigations were carried out concerning the above mentioned questions.
Results
1. Oxygen uptake of cerebral tissues from the intoxicated animals was normal in the ordinary Krebs-Ringer medium containing Ca, but lactate formation was decreased 43% as compared with the control. In this way, the results by Utena and others were reconfirmed.
2. It was demonstrated that potassium effect was normal in cerebral tissues from animals with chronic methamphetamine intoxication.
3. Lactate formation remained the same in control cerebral tissues, whether or not they were incubated in the saline added with dialyzed serum from normal animals, whereas it showed 50% decrease when these tissues were acted upon by dialysed serum from the intoxicated animals. It was namely demonstrated that there must be a glycolysis-inhibiting factor or factors in the serum from the intoxicated animal.
4. Oxygen uptake and lactate formation were increased slightly in cerebral tissues from both controls and the intoxicated animals, when they were acted upon by non-dialyzed serum. Moreover, the abnormalities in cerebral tissue metabolism of the intoxicased animals disappeared as in the case of potassium effect.
5. The relation between the inhibitory action and the serum concentration in medium was described.
6. The inhibitory action of the serum was lost when it was heated at 60°C for 30 minutes.
7. Dialyzed sera from the intoxicated and the normal animals were compared each other with regard to percentages of protein fractions. No apparant difference was revealed.
8. In the intoxicated animals normal blood sugar level, enlargement of the adrenals and remarkable involution of the thymus were observed.