Calcium, liver content

As can be seen from the results in Table V, fluoride levels in plasma, liver and kidney increased 3 to 8 times but there was no significant effect on the calcium or phosphorus content, although the kidney Ca level in fluoride treated rats was 40 higher than in the controls. Whereas the normal exposure to fluoride from air, food and water did not cause any increase in soft tissue levels, more than ten times the normal levels in soft tissues, including liver and kidney, were found in human fatalities due to fluoride poisoning (15). 

Exposure-dependent decrease in respiration rate 53 and content of sodium, potassium, and calcium in gill, brain, muscle and liver. At 48 h, whole animal respiration rate decreased 51%, tissue Na content by 28-40%, tissue K content by 28-34°/ o, and tissue Ca content by 19-36%... 

The EPMA technique as applied to calcium has been improved by Somlyo in particular. Typically samples are rapidly frozen and sectioned at low temperatures (— 130°C) to preserve the in vivo localization of diffusible ions and molecules. Spatial resolutions of 10 nm or better have been attained on a 100 nm thick freeze-dried cryosections. The minimal detectable concentration, which requires some signal averaging, is approximately 0.3 mmol Ca per kg dry specimen (i.e., 10 ppm). The calcium content of mitochondria and endoplasmic reticulum in rat liver cells has been studied by EPMA (see Table 3.1). ... 

Calcium chromate has been shown to induce cytoplasmic petite mutations in mitochondria of Saccharomyces cerevisiae K Calcium chromate also dramatically depressed the content of the mitochondrial gene products cytochrome aa3 and cytochrome b, in whole yeast cells. Chromate ( 8 nM) was readily taken up by rat thymocytes and after 30 min 9% of the Cr was found in the mitochondria although 62% was found in the nuclei . Isolated rat thymus mitochondria and nuclei readily took up CrOj . After one hour incubation of Erlich ascites tumor cells with CrOj (380 /nuclear fraction and 12% was in the mitochondrial-microsomal fraction. Levels of chromium in rat liver mitochondria reached a plateau six hours after i.v. injection of chromate (0.02 mg/kg) and remained at that level through 5 days. Liver nuclear chromium levels in the same animals, although similar to mitochondrial levels at 6 h, reached a maximum at 12 h and steadily decreased after that time. Therefore the nuclear chromium levels were lower than the mitochondrial chromium levels at later times (24-120 h) after injection. The subcellular distribution of chromium in the liver of rats injected i.v. with chromate (0.56 mg/kg) was also found to be time dependent in another study. The distribution of chromium in rat liver mitochondria increased from 5% at 15 min to 21% at 72 h and also increased in the nuclear fraction from 22% at 15 min to 52% at 72 h. Incubation of isolated rat liver mitochondria with chromate (0.3-16.6 electron transport chain of the mitochondrial iner membrane. 

Cytochrome c release from intact rat liver mitochondria depended strictly on pore opening and not on membrane potential, and a calcium-dependent permeabiUty transition-enhancing oxidative stress also augmented cytochrome c release (Kantrow et al. 2000). Compared to mitochondria from normal mouse Uvers, fatty Uver mitochondria had a 50 % reduction in cytochrome c content and produced superoxide anion at a grater rate (Yang etal. 2000). 

The content of magnesium in the body of an adult is about 25-40 g. This accounts for about 60% of the content of the skeleton. The highest concentrations of magnesium in soft tissues are found in the pancreas, liver and skeletal muscles. Blood and extracellular fluids contain only 1% of the total amount of magnesium in the body. Calcium is quantitatively the major mineral component in the human body. The total amount is about 1500g, with 99% of this being in bones and teeth as calcium phosphate. 

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