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T C Raghuram

Publications and source records attributed to T C Raghuram.

27 records · Page 2Linked to original sources
PubMed1976

Effect of vitamin B6 on leucine-induced changes in human subjects.

Distrubances in the tryptophan-niacin pathway seen in endemic pellagra among sorghum eaters have been ascribed to high dietary intake of leucine. Vitamin B6 plays an important role in several steps of this pathway. Therefore, studies on possible metabolic interrelations between excess dietary leucine and vitamin B6 were undertaken in normal healthy human subjects. The results indicated that vitamin B6 could successfully counteract the effects of leucine on quinolinic acid excretion in urine, and on in vitro nicotinamide nucleotide synthesis by erythrocytes, and also could correct the abnormalities of 5-hydroxytryptamine metabolism induced by excess leucine. These observations suggest that vitamin B6 nutritional status may have a contributory role in the pathogenesis of endemic pellagra.

Adult↗
PubMed1975

Serotonin metabolism is pellagra.

Altered mental status is common in pellagrins. We evaluated the mental status of pellagrins in relation to the neurohormone, serotonin or 5-hydroxytryptamine (5-HT). Levels of 5-hydroxyindoleacetic acid (5-HIAA), an end product of serotonin in the urine and cerebrospinal fluid (CSF), and of platelet 5-HT were determined in a group of pellagrins and in normal subjects. The results indicated that the 5-HT concentration was reduced in platelets and 5-HIAA excretion in urine was below normal levels. The 5-HIAA concentration in CSF was also reduced, suggesting a decrease in 5-HT functional activity in the brain.

Adult↗
PubMed1975

Role of vitamin B6 on leucine-induced metabolic changes.

Administration of leucine at 3% level in the diet has been shown to increase tryptophan oxygenase activity and to decrease kynureninase activity in the liver and to increase quinolinic acid excretion in the urine of rats fed low amounts of vitamin B6 (0.5 mug/g diet). Vitamin B6 at 3 mug/g of diet was able to reverse the effects of leucine on enzyme activities, but not on quinolinic acid excretion. Isoleucine at 0.2% level could counteract the leucine effect on kynureninase but not on tryptophan oxygenase. Administration of leucine also decreased the 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in the brain. Simultaneous administration of isoleucine could counteract the effects of leucine on brain 5-HT and 5-HIAA partially at low amount of vitamin B6 but completely at higher levels of vitamin B6 in the diet.

Animals↗
PubMedDate not supplied

Influence of dietary restriction and protein deficiency on plasma half-life and tissue distribution of tetracycline in rats.

1. The effects of dietary restriction and protein deficiency on plasma half-life and tissue distribution of tetracycline were studied in rats by feeding either a 20% protein diet in restricted quantity or a 9% protein diet ad lib and compared with rats given a 20% protein diet ad lib (control group). 2. It was observed that half-life of tetracycline was shortened and that plasma and tissue Cmin levels at steady-state were lower in undernourished rats. Tissue concentrations in liver, kidney, muscle and bone correlated well with plasma levels. A high degree of correlation was also observed between plasma and tonsillar concentrations of tetracycline in human subjects. 3. These studies indicate that undernourished subjects may require an altered dosage regimen of tetracycline to maintain effective steady-state concentrations of the drug.

Adolescent↗