Následující řádky přinášejí informaci o významném buněčném mechanismu, který pomáhá udržovat energetickou rovnováhu buněk v okamžicích náhlého zvýšení požadavku na dodávku energie. Tento mechanismus také usnadňuje přenos energeticky bohatých substrátů v buněčném prostoru k místům jeho spotřeby a je zvláště rozvinutý v buňkách, jejichž požadavky na dodávku energie v průběhu času značně kolísají a jsou schopné vysokého výkonu. Můžeme jej pozorovat ve svalových vláknech, srdečních myocytech, neuronech, ale i ve spermatických buňkách, které se po probuzení k aktivitě pokouší vyhrát závod s ostatními a splnit tím svoji biologickou úlohu., The article presents information on an important cell mechanism that helps to maintain the energy balance in cells at moments when there is a sudden increase in demand for energy supply. This mechanism also facilitates the transfer of energy-rich substrata in cellular space to the locations of its consumption, and it is particularly well-developed in cells that are capable of high performance and their energy requirements vary considerably over time. We can observe it in muscle fibres, cardiac myocytes, neurons and sperm cells., and Jitka Žurmanová.
The apolipoprotein A-V (apo A-V) plays an important role in regulation of triglyceride (TG) concentration in serum. To better understand how apo A-V affects triglyceridemia and glucoregulation, the lipoprotein lipase (LPL) activity was determined using intravenous fat tolerance test (IVFTT) and oral glucose tolerance test (oGTT) was performed in carriers of apolipoprotein A-V gene ( APOAV) variants known to be associated with increased triglyceridemia. Twelve carriers of 19W variant, 16 carriers of -1131C variant, 1 combined heterozygote and 16 control subjects homozygous for wild type variants (19S/-1131T) were selected from a population sample and matched with respect to body mass index and age. The APOAV variants carriers had increased TG, very low density lipoprotein-TG, and apo B concentrations (p < 0.05). The LPL activity evaluated as k2 rate constant for clearance of Intralipid® was 14 % lower in APOAV variants carriers. The depression of nonesterified fatty acids (NEFA) concentration after glucose load was delayed in APOAV variants carriers in spite of the same insulinemia and glycemia. Our results suggest that variants of APOAV combined with increased triglyceridemia are associated with lower LPL activity in vivo and with disturbances of regulation of NEFA concentration after glucose load., J. Kovář, V. Adámková., and Obsahuje bibliografii a bibliografické odkazy
The European Molecular Biology Organization organized a meeting in Prague October 1-3. At this symposium several topics were discussed: biology and genetics of mitochondria in relation to cancer; the role of mitochondria-targeting compounds in cancer suppression (including BH3 mimetics); mitochondria as transmitters of death receptor-induced apoptosis; regulation of apoptosis and the interplay of mitochondria with other organelles p53 and mitochondria in apoptosis regulation; and the role of mitochondria in targeting cancer stem cells. and Jiří Neužil, Ladislav Anděra a Alois Kozubík.
Patch clamp method developed more than 30 years ago is widely used for investigation of cellular excitability manifested as transmembrane ionic current and/or generation of action potentials. This technique could be applied to measurement of ionic currents flowing through individual (single) ion channels or through the whole assembly of ion channels expressed in the whole cell. Whole cell configuration is more common for measurement of ion currents and the only one enabling measurement of action potentials. This method allows detailed analysis of mechanisms and structural determinants of voltagedependent gating of ion channels as well as regulation of channel activity by intracellular signaling pathways and pharmacological agents., M. Karmažínová, L'. Lacinová., and Obsahuje bibliografii a bibliografické odkazy