Rapid uptake mode

Soriano, M.E., Nicolosi, L., and Bernardi, P., 2004, Desensitization of the permeability transition pore by cyclosporin A prevents activation of the mitochondrial apoptotic pathway and liver damage by tumor necrosis factor-alpha, J. Biol. Chem. 279, pp. 36803-36808 Sparagna, G.C., Gunter, K. K., Sheu, S. S., and Gunter, T. E., 1995, Mitochondrial calcium uptake from physiological-type pulses of calcium. A description of the rapid uptake mode, J. Biol. Chem. 270, pp. 27510-27515... 

Polarographic studies of a mitochondrial fraction from Hymenolepis diminuta showed that of four substrates tested, DL-glycerol-3-phosphate was the most rapidly oxidized, but the highest respiratory control ratio (1.7) was obtained with dl-isocitric acid. With isocitrate as substrate oxyclozanide at 1.61 nM stimulated O uptake and relieved oligomycin inhibition of adinosine diphosphate-stimulated respiration, but at concentrations above 2 pM progressively inhibited O uptake. Rafoxanide, niclosamide, 3,4,5-tribromo-salicylanilide, nitroxynil, resorantel, di-chlorophen, and 2,4-dinitrophenol exhibited effects similar to those of oxyclozanide on the respiration in cestode mitochondria. The relative potencies were compared and the possible mode of action discussed [38]. 

No specific cargo molecules have been identified so far, which makes it difficult to follow the intracellular fate of unspecific internalized material. It appears that the uptake via noncoated vesicles is rapidly upregulated in response to inhibition of the clathrin-mediated pathway. Because of the lack of detailed information, no statements can be made about the role of this mode of internalization for the uptake of liposomes. 

Collis, L. et al., Rapid hyaluronan uptake is associated with enhanced motility implications for an intracellular mode of action, FEBS Lett., 440, 444, 1998. 

Laboratory studies have suggested that there are three modes of transport for silicic acid (reviewed by Martin-Jezequel et al., 2000) first, silicic acid may be rapidly transported across the cell membrane, following surge uptake kinetics. This occurs primarily in Si-starved cells with cell quotas (Droop, 1968, 1973) near minimal values. Second, sdicic acid uptake can be controlled internally, presumably due to regulation ofsihcaprecipitation and deposition (e.g., Hildebrand et al., 1997). Third, silicic acid uptake may be controlled externally due to substrate hmitation. 

Its mode of action is similar to that of chlorsulfuron. Within hours of uptake by the sensitive weeds there is a rapid inhibition of growth, then a yellowing, tissue necrosis and death. 

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