Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.9.3.1 (cytochrome oxidase)
 8,822 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this study was to evaluate the effect of lead and excess zinc on the adaptation of mitochondria from skeletal muscles to physical effort. Rats were intoxicated once a week for 12 weeks by subcutaneous injection of the solution containing 2 mg Zn+2 and/or 3 mg Pb2+ per kg of body weight. During the last 6 weeks, 6 times weekly, rats performed endurance training which involved swimming 15 minutes daily with additional load of 5% of the body weight. The activities of isocitrate (ICD), malate (SDH), succinate (MDH) dehydrogenases, cytochrome oxidase (COX) and protein content (PM) were determined in the mitochondrial fractions obtained from the soleus muscle (ST fibres), and from the superficial (FTb fibres) and deep (FTa fibres) parts of the gastrocnemius muscle. In the control group (C), which was injected with saline, higher activities of ICD and MDH were obtained in FTa and FTb fibres than in the ST fibres. SDH and COX had higher activities in FTa and ST compared to FTb fibres. Zinc treatment (Zn) caused diminution of ICD, SDH and COX activities in ST fibres. Lead intoxication (Pb) resulted in a decrease of MDH activity in all fibre types, and in a decrease of SDH activity in ST fibres. Simultaneous action of zinc and lead produced an increase in ICD activity and diminution of COX activity in FTb fibres. It also resulted in an increase of SDH and decrease of COX activity in ST fibres. These results suggest that the ST fibres are more susceptible to disturbances of adaptation to physical exercise caused by zinc and lead. There are no signs of uniform antagonism between zinc and lead action in the processes under investigation.
 ...
PMID:The activity of mitochondrial enzymes in the muscles of rats subjected to physical training and subchronical intoxication with lead and zinc. 248 52

Quantitative cytochemistry of cytochrome oxidase (C.O.) was implemented in human brains to measure C.O. activity in the 3 main divisions of the inferior colliculus (IC): central (ICC), dorsal (ICD), and external (ICE). Units of C.O. activity (micromol/min/g tissue wet weight) were quantified in cellular compartments (overall average, neuropil, perikaryon, and dendrites) at the light microscope level using microdensitometry calibrated with C.O. activity standards measured spectrophotometrically. In a non-AD (Alzheimer's disease) control group (mean age = 79.6 +/- 3.1 years, postmortem time = 6.9 +/- 1.6 h), the ICC and ICD demonstrated higher (p < 0.008) overall average activities (mean = 183.40 +/- 18.7 and 184.98 +/- 45.1 units, respectively) relative to the ICE (56.46 +/- 15.9 units). Comparison of cellular morphometry (soma and nucleus area, perimeter, and diameter) revealed that the ICC contained cells of significantly larger soma size than in both the ICD and ICE (p < 0.002). The distribution of soma diameters in the ICC of controls showed a clear bimodality, enabling the typing of the cells into larger and smaller than average soma diameter. Brains from patients with Alzheimer's disease (AD; mean age = 78.3 +/- 2.9 years, postmortem time = 6.5 +/- 1.3 h) were compared with the non-AD controls. Significant group differences were found only in the large cells of the ICC. The AD large cells showed a decrement in C.O. activity relative to the corresponding controls in overall average activity (p < 0.032) and in peak activity of neuropil near the soma (p < 0.012). These findings provide the first quantitative cytochemical data of C.O. activity in humans. They also suggest that cellular alterations in C.O. metabolism in AD affect predominantly specific groups of larger projection neurons while neighboring neurons are spared.
 ...
PMID:Quantitative cytochemistry of cytochrome oxidase and cellular morphometry of the human inferior colliculus in control and Alzheimer's patients. 910 47