+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

4-Aminopyridine activates calcium influx through modulation of the pore-forming purinergic receptor in human peripheral blood mononuclear cells

, : 4-Aminopyridine activates calcium influx through modulation of the pore-forming purinergic receptor in human peripheral blood mononuclear cells. Canadian Journal of Physiology and Pharmacology 82(1): 50-56

We investigated whether 4-aminopyridine (4AP), a drug recently linked to calcium influx and apoptosis, also affected purinergic receptor channels that are known to play an important role in the activation of T lymphocytes. The application of 4AP induced a rise in (Ca2+)i that was sensitive to nickel. This action was also observed in cells in which calcium reserves were emptied using thapsigargin (Tg). However, it was not present in the absence of extracellular Ca2+, despite full internal reserves. Adenosine trisphosphate (ATP), a partial agonist and a physiological activator of purinergic receptors, also stimulated Ca2+ entry independently of the calcium release from internal compartments. The effects of 4AP and ATP were not additive when studied on the same population of cells. KN-62 inhibited an increase in calcium entry induced by 4AP, while brilliant blue G (BBG) prevented it, supporting the hypothesis that purinergic P2X7 receptors are involved in this action. Furthermore, 4AP allowed entry of ethidium bromide (314 Da) but not propidium iodide (415 Da) into the cell, also corroborating the involvement of P2X7 pores. The presented results demonstrate, for the first time in human mononuclear cells isolated from healthy volunteers, that the P2X7 channel pore is involved in the action of 4AP and intervenes in the sustained calcium entry induced in response to 4AP.


PMID: 15052305

DOI: 10.1139/y03-128

Other references

Wandelt, P.M.oz, W., 1992: A rapid method for measuring yield in semichemical pulping processes. Tappi journal 75(3): 203-205

Kornilov N.A., 1971: Stages in the formation and alteration of rich iron ores in Precambrian formations. Geologicheskiy Zhurnal (Kiev, 1968): , Pages 130-137. 1971.

Ueki Y.; Kawada T.; Masuda K., 1979: Production and morphological characteristics of spirosome of enterobacteriaceae especially spirosome of yersinia enterocolitica. Japanese Journal of Bacteriology 34(1): 286

Greenburg, R.R.; Risebrough, R.W.; Anderson, D.W., 1979: p,p'-DDE-induced changes in the organic and inorganic structure of eggshells of the mallard, Anas platyrhynchos. Toxicology and Applied Pharmacology 48(2): 279-286

Tugizov, S.; Maidji, E.; Xiao, J.; Pereira, L., 1997: Human cytomegalovirus gB, an envelope glycoprotein, contains signals for apical transport in epithelial cells and regulates virus release. Molecular Biology of the Cell 8(SUPPL ): 409A, Nov

Rumpel, M.; Dannecker, B.; Voss, A.; Moeller, M.; Moormann, C.; Graf, T.; Ahmed, M.Abdou., 2013: Thermal behavior of resonant waveguide-grating mirrors in Yb:YAG thin-disk lasers. We present the experimental investigations of different designs of resonant waveguide-grating (RWG) mirrors, used as intracavity folding mirrors in an Yb:YAG thin-disk laser (TDL). The investigation was focused on the rise of the surface temperatu...

Santos, R.; Gliessman, S.; Cecon, P., 2002: Crop interactions in broccoli intercropping. The research goals were to evaluate crop suitability to intercropping systems, to evaluate a population density limit to successful intercropping and to study the main factors responsible for crop performance when intercropped. Three experiments w...

Azzopardi, E.A.; Ferguson, E.L.; Thomas, D.W., 2015: Development and validation of an in vitro pharmacokinetic/pharmacodynamic model to test the antibacterial efficacy of antibiotic polymer conjugates. This study describes the use of a novel, two-compartment, static dialysis bag model to study the release, diffusion, and antibacterial activity of a novel, bioresponsive dextrin-colistin polymer conjugate against multidrug resistant (MDR) wild-typ...

Heller, K.M., 1922: Springende Blutenkelche verursacht durch ein neues Apion (Col). Entomologische Mitteilungen Berlin, 11: 52-54

Benninger Larry K.; Krishnaswami S., 1981: Sedimentary processes in the inner New York Bight; evidence from excess (super 210) Pb and (super 239,240) Pu. Earth and Planetary Science Letters 53(2): 158-174