While adenylate kinase catalyses the conversion of some ADP to AMP to meet short term energy needs of the brain, in ischemic tissue, the adenine nucleotide
pool is depleted by the conversion of AMP to inosine and hypoxanthine.
This enzyme generates extracellular adenosine from AMP, as previously mentioned, and its activity is the rate-limiting step of adenosine formation from adenine nucleotides
in most tissues [49, 51].
Tight binding of adenine nucleotides
to beef-heart mitochondrial ATPase.
Mitochondrial [Ca.sup.2+] could activate three dehydrogenases of the TCA cycle (pyruvate dehydrogenase, isocitrate dehydrogenase, and oxoglutarate dehydrogenase), the ATP synthase (complex V), and the adenine nucleotide
translocase and then increase the generation of ROS [106-108].
For the kinetic experiments of the extracellular catabolism of adenine nucleotides
and adenosine, strips from the longitudinal muscle with the myenteric plexus attached (LM-MP) were mounted in a 2mL organ bath.
Therefore, the relation between the ectonucleotidases and TH was also investigated in brain cell culture from rats submitted to neonatal hypothyroidism and demonstrated that the adenine nucleotides
hydrolysis was altered in cerebellar and hippocampal astrocytes from immature hypothyroid rats.
Separations of Cr, PCr, and adenine nucleotides
were performed on a 2.1 x 100 mm ACQUITY UPLC HSS T3 column packed with 1.7 [micro]m particles (Waters) by recording the optical density simultaneously at 210 nm for Cr and PCr and at 254 nm for adenine nucleotides
To measure the secretory response of the platelets obtained from experimental subjects, the platelets were activated with 2[micro]M collagen and the level of secretion was measured in terms of release of serotonin, adenine nucleotides
, PPi, and Pi (Figure 1).
The mitochondrial permeability transition pore (MPTP), a multi-protein complex including the voltage-dependent anion channel (outer membrane), the adenine nucleotide
translocase (ANT; inner membrane), cyclophilin-D (mitochondrial matrix) and Bc1-2 family members (Bcl-2, Bad and Bax), is formed at the contact site between the mitochondrial inner and outer membranes (7).
Because AICAR inhibits AMP deaminase (AMPDA), an increased AICAR level leads to the release of intracellular adenine nucleotides
and adenosine, either or both, into the extracellular space.
The effect of graduated exercise on the concentration of adenine nucleotides
Booth and colleagues suggest that the delayed fatigue may be due to loss of adenine nucleotides
needed to make ATP that occurs during the adenylate kinase reaction.
Decreased resting levels of adenine nucleotides
in human skeletal muscle after high-intensity training.
This phenomenon could be linked to the finding that significant depletion of ATP and adenine nucleotides
(which may indicate that they had been metabolized to urate) occurred only in rat liver slices incubated in a medium containing both glycerol and ethanol (9).
One perspective on the transport role, formulated as the CP "shuttle" (Bessman and Geiger, 1981) and later CP "circuit" (Wallimann et al., 1992), hypothesizes that there are separate pools of adenine nucleotides
at source and sink and that the CP/CK system provides the energetic link between the two sites.