1. On storage of rat liver mitochondria at 0 degrees , water content, total amino acid content and leakage of protein all rose steadily over a 72hr. period. The initial ratio of intramitochondrial to extramitochondrial amino acid concentration lay between 18 and 24. Initially this rose, but it then fell to 1.9 at the end of storage. The concentration gradient between internal and external amino...

1. A method was devised to allow determination of intramitochondrial aspartate amino-transferase activity in suspensions of intact mitochondria. 2. Addition of purified rat liver mitochondrial aspartate aminotransferase to suspensions of rat liver mitochondria caused an apparent increase in the intramitochondrial enzyme activity. No increase was observed when the mitochondria were preincubated ...

Kidney and liver mitochondria of rat, rabbit and guinea pig are able to transform 3-hydroxy-3-methylglutarate into acetoacetate, whereas ox liver mitochondria and rat mitochondria of heart, diaphragm and brain do not exhibit such an activity. Starvation and streptozotocin treatment decreases the formation of acetoacetate from 3-hydroxy-3-methylglutarate. Addition of acetoacetate and succinate t...

Axonal mitochondria are recruited to synaptic terminals in response to neuronal activity, but the mechanisms underlying activity-dependent regulation of mitochondrial transport are largely unknown. In this paper, using genetic mouse model combined with live imaging, we demonstrate that syntaphilin (SNPH) mediates the activity-dependent immobilization of axonal mitochondria through binding to KI...

L-Proline is oxidized to pyrroline-5-carboxylic acid in intact plant mitochondria by a proline dehydrogenase (EC 1.4.3) that is bound to the matrix side of the inner mitochondrial membrane (TE Elthon, CR Stewart [1981] Plant Physiol 67: 780-784). This investigation reports the first solubilization of the L-proline dehydrogenase (PDH) from plant mitochondria. The supernatant from NP-40-treated e...

Previous work has indicated that respiratory activity of mitochondrial preparations prepared from lactating mammary tissue is often much lower than that of mitochondria isolated from other organs such as the liver. Initial studies in our own laboratory also found that mammary mitochondria prepared from lactating mice had much lower ATP synthesis activity than those isolated from liver tissue ob...

Kidney function declines with advancing age and mitochondria have been implicated. In the present study we have examined the integrated function of mitochondria isolated from kidneys of 6- and 24-month-old Fischer 344 rats. OXPHOS (oxidative phosphorylation) of intact mitochondria and cytochrome c oxidase activity in permeabilized mitochondria were determined with polarographic assays. The acti...

Previous studies demonstrated that CSE induces oxidative stress and its consequences on isolated mitochondria obtained from lung, heart and brain which may provide insight into the role of CSE in human health and disease. The present study was carried out to further characterize and compare toxic effect of CSE extract on isolated mitochondria obtained from either a directly contacting tissue (i...

Well-coupled mitochondria of hematopoietic tumors were iso lated from mouse erythroleukemia and rat chloroma tumors grown in male DBA/2J mice and Long-Evans rats, respectively. We used erythroleukemia and chloroma mitochondria to deter mine their ability to utilize glutamine as an energy source for adenosine triphosphate formation. Oxypolarographic tests showed the following, (a) Presence of a ...

Within neurons, mitochondria are nonuniformly distributed and are retained at sites of high activity and metabolic demand. Glutamate transport and the concomitant activation of the Na(+)/K(+)-ATPase represent a substantial energetic demand on astrocytes. We hypothesized that mitochondrial mobility within astrocytic processes might be regulated by neuronal activity and glutamate transport. We im...