Manganese plasma concentrations

The possible hnk between hypermanganesemia and cholestasis has been investigated in patients receiving long-term parenteral nutrition (68). The authors concluded that cholestatic liver disease does not contribute to increased blood manganese concentrations in such patients, and that plasma concentrations reflect recent manganese exposure and impaired excretion when cholestasis is present. They also emphasized that serum concentrations are a poor marker and that erythrocyte manganese concentrations should be used instead. 

The plasma concentration of labeled manganese reached a peak of 10.2 pg/mL at 5 minutes postdosing and was quickly distributed into the following organs (values given as ug equivalents of compound/g) pancreas, 10.2 liver, 4.0 kidneys, 3.6 testes/ovaries, 1.7 spleen, 1.0 heart, 0.9 and brain,... 

Coal contains several elements whose individual concentrations are generally less than 0.01%. These elements are commonly and collectively referred to as trace elements. These elements occur primarily as part of the mineral matter in coal. Hence, there is another standard test method for determination of major and minor elements in coal ash by ICP-atomic emission spectrometry, inductively coupled plasma mass spectrometry, and graphite furnace atomic absorption spectrometry (ASTM D-6357). The test methods pertain to the determination of antimony, arsenic, beryllium, cadmium, chromium, cobalt, copper, lead, manganese, molybdenum, nickel, vanadium, and zinc (as well as other trace elements) in coal ash. 

Yanik M, Kocyigit A, Tutkun H, Vural H, Herken H. 2004. Plasma manganese, selenium, zinc, copper, and iron concentrations in patients with schizophrenia. Biol Trace Elem Res 98 109-117. 

Table I. Correlation Between Whole Blood Manganese Concentration and Plasma Anticonvulsant Concentrations in Epileptic Patients...

Figure 1. Whole blood manganese levels in epileptic patients vs. medication index. Whole blood manganese was measured by atomic absorption spectrophotometry. The medication index is a composite measure of anticonvulsant concentrations in plasma as a relationship of each anticonvulsant to its therapeutic range. The medication index increases as a function of the relative concentration of each anticonvulsant and as a sum of all anticonvulsant concentrations. There was no correlation between whole blood manganese and medication index (r = -0.236.)...

The heavy line in Figure 3 represents the mean curve (n=ll) for the change in plasma manganese and the other lines show the typical plasma responses of individual subjects (n 5). The mean increase in plasma manganese peaked at hour 1, at approximately 103% above fasting. The mean concentrations of plasma manganese were 0.64, 1.29, 1.12, 0.94 and 0.75 ug/L at hours 0,1,2,3, and 4 postdose,... 

Figure 1. Variation in fasting concentrations of plasma manganese within and among normal subjects (n=ll). Number in parentheses indicates the number of measurements made on the same individual. Straight line indicates mean value for the group.

Weanling, Wistar and RICO (genetically hypercholesterolemic) rats were placed on manganese-deficient (0.12 pg Mn/g) or manganese-sufficient (100.12 pg Mn/g) diets. Plasma total, VLDL- and HDL-cholesterol levels, and liver cholesterol and lipid concentrations were not affected by the treatment used. These results suggest that dietary manganese deficiency does not result in significant alterations in cholesterol and lipid metabolism in the rat (8). 

Synthetic tin protoporphyrin is a specific inhibitor of heme oxygenase and reduces plasma bilirubin concentrations in both adults and neonates, thereby preventing jaundice (1-3). A variety of heme analogues, such as tin, zinc, chromium, and manganese metalloporphyrins, act by competitive inhibition of cleavage of heme to biliver-din and carbon monoxide. Stannic porphyrins seem to be the most effective. The adverse effects are few, with only occasional erythema attributable to the phototoxicity of the metalloporphyrins. 

Concentrations of vitamins and trace elements are measured most often in plasma or serum this provides a reliable index of status for only a few of them (e.g., vitamin B52 or vitamin D). For others (e.g., folate or selenium), their concentrations only may reflect the adequacy of recent intake. An excessive provision of elements such as manganese and chromium may also be detected by high serum concentrations. ... 

Concentrations of manganese in select human and animal tissues are presented in Table 2-6 and concentrations of manganese in plasma and serum in infants of differing ages and adults are presented in Table 2-7. 

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