Regional brain ascorbic acid distribution: its functional relationship to appetite and leptazol-induced convulsions in guinea-pigs.
The distribution of ascorbic acid has been compared in the fore-, mid- and hind-brains of guinea-pigs maintained on a scorbutogenic diet alone, or the diet with supplementary Vitamin C, or the supplemented diet and a terminal convulsant dose of leptazol after 27 days. At the beginning of the investigation, mid-brain ascorbic acid concentrations were similar in both sexes and highest in the mid-brain. After 27 days on the supplemented diet, levels of ascorbic acid were raised in all three brain sections and were still highest in the mid-brains. In the scorbutic group, ascorbic acid concentrations had not changed from control levels in the mid-brain, but had fallen in the other two sections. In a dose-range of 40-60 mg/kg, leptazol caused an increase in convulsive index, and progressive depletion of brain ascorbic acid. No change occurred in fore-brain ascorbic acid, a reduction took place in the hindbrain, and the greatest fall occurred in the mid-brain. It is concluded that ascorbic acid plays an essential role in mid-brain metabolism, and that the convulsant effect of leptazol is influenced by an interaction with brain ascorbic acid.
D000818:Animals; D001069:Appetite Regulation / Q000187:drug effects*; D001205:Ascorbic Acid / Q000502:physiology*; D001206:Ascorbic Acid Deficiency / Q000378:metabolism; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006168:Guinea Pigs / Q000378:metabolism*; D008297:Male; D010433:Pentylenetetrazole; D012640:Seizures / Q000139:chemically induced / Q000378:metabolism*; D012737:Sex Factors
D001205:Ascorbic Acid; D010433:Pentylenetetrazole