Table 1.
Historical studies on Mn excretion and their main findings
| References | Findings |
|---|---|
| Reiman and Minot, 1920 (59) | Developed colorimetric assay for determining blood and tissue Mn levels. Liver contains the highest amount of Mn in human tissues collected from 14 autopsies. |
| Drinker and Shaw, 1921 (60) | Liver is a major site of Mn accumulation in cats intravenously injected with MnO2. |
| Lund et al., 1921 (61) | Mn accumulates primarily in the liver 1 h after intravenous MnO2 injection in several other animal species. |
| Drinker et al., 1923 (62) | Mn is detected in bile samples collected from rabbits receiving intravenous Mn injections. |
| Mella, 1924 (63) | Observed movement disorders (rigidity, hand tremors) and signs of brain and liver injury in rhesus monkeys receiving intraperitoneal Mn injections. |
| Findlay, 1924 (64) | Repeated Mn injections cause liver cirrhosis in rats and rabbits. |
| Greenberg and Campbell, 1940 (57) | >90% of orally or intraperitoneally administered Mn radioisotopes are excreted in the feces of rats. |
| Greenberg et al., 1943 (26) | 37.3% of injected Mn radiotracer dose is observed in bile after 48 h in rats with artificial gallbladders. |
| Cotzias and Greenough, 1958 (24) | Rate of Mn excretion is affected by levels of dietary Mn, but not by supplement of other metals (Fe, Cr) |
| Bertinchamps et al., 1966 (22) | When hepatobiliary excretory pathway of Mn is saturated, auxiliary excretion occurs through the gut. |
| Papavasiliou et al., 1966 (25) | Biliary obstruction impairs Mn excretion, fecal obstruction abolishes Mn excretion. |
| Mena et al., 1967 (65) | Healthy Mn miners eliminate injected radioisotope Mn faster than miners afflicted with Mn toxicity. |
| Klaassen, 1974 (66) | Mn concentration in bile is ∼150-fold greater than Mn concentration in plasma. |
| Miller et al., 1975 (67) | Neonatal mice show almost complete retention of Mn radiotracer until PND17, when Mn excretion seemingly presents a sudden increase. |
| Ballatori et al., 1987 (68) | Neonatal mice excrete Mn at a lower rate than adults (∼50% lower biliary excretion). Manganese excretory pathways are saturated at relatively low doses of Mn supplement (10 mg Mn/kg). |
Mn, manganese; PND17, postnatal day 17.