Mitochondrial oxidation organization

ATP certainly fulfils the criteria for a NT. It is mostly synthesised by mitochondrial oxidative phosphorylation using glucose taken up by the nerve terminal. Much of that ATP is, of course, required to help maintain Na+/K+ ATPase activity and the resting membrane potential as well as a Ca +ATPase, protein kinases and the vesicular binding and release of various NTs. But that leaves some for release as a NT. This has been shown in many peripheral tissues and organs with sympathetic and parasympathetic innervation as well as in brain slices, synaptosomes and from in vivo studies with microdialysis and the cortical cup. There is also evidence that in sympathetically innervated tissue some extracellular ATP originates from the activated postsynaptic cell. While most of the released ATP comes from vesicles containing other NTs, some... 

All organic tin compounds inhibit mitochondrial oxidative phosphorylation (hydrolysis of adenine triphosphate) and brain glucose oxidation and are toxic. Very little data are available on inorganic tin. 

Thyroxine is one of the few hormones for which unequivocal effects on isolated biochemical systems can be observed in particular, it has been shown that thyroxine at high concentrations has a direct effect on mitochondrial oxidation. Tissues from animals which have been injected with thyroid extracts or purified thyroxine show a raised oxygen consumption, particularly in liver and muscle. Similarly the addition of thyroxine to tissue slices of the same organs results in increased oxidation. Thyroxine seems to be especially trapped by the mitochondria, where it stimulates the... 

Photosynthetic carbon dioxide fixation into oi-keto acids has recently been found to be the major pathway in some organisms. The process appears to be essentially a reversal of the mitochondrial oxidative decarboxylation processs. The photoreduction is mediated through a ferredoxin system similar to the photosynthetic nicotinamide coenzyme reductase. The involvement of lipoic add has not yet been shown, but it would be expected and could provide the long-sought role of lipoate in photosynthesis. 

The thylakoid membrane is asymmetrically organized, or sided, like the mitochondrial membrane. It also shares the property of being a barrier to the passive diffusion of H ions. Photosynthetic electron transport thus establishes an electrochemical gradient, or proton-motive force, across the thylakoid membrane with the interior, or lumen, side accumulating H ions relative to the stroma of the chloroplast. Like oxidative phosphorylation, the mechanism of photophosphorylation is chemiosmotic. 

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