[Effect of caffeine on the processes of intracellular Ca2+ concentration regulation in isolated snail neurons].
The Ca2+ indicator Fura-2 was used to measure changes of cytoplasmic free Ca2+ concentration ([Ca2+]in) in isolated neurons of the snail Helix pomatia occurring through prolonged plasma membrane depolarization. An amplitude of Ca2+ response did not practically depend on value of depolarization in the presence of 5 mmol/l of caffeine unlike normal solution, which permitted suggesting that caffeine activated calcium-dependent Ca2+ release from the intracellular stores, which was a main factor of [Ca2+]in increase during depolarization. The processes of [Ca2+]in relaxation to the rest levels were approximated monoexponentially and occurred 2 times more rapidly in caffeine than in normal solution. An increase of the [Ca2+]in relaxation rate was provided probably, by a rise in the efficiency of the intracellular Ca2+ pumps able to decrease the rest level of [Ca2+]in even lower than that one under normal extracellular solution conditions.
Usachev
Iu M
IuM
Mironov
S L
SL
D000818:Animals; D002110:Caffeine / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D016257:Fura-2; D006372:Helix, Snails / Q000187:drug effects / Q000378:metabolism; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism
D002110:Caffeine; D002118:Calcium; D016257:Fura-2
Vliianie kofeina na protsessy reguliatsii vnutrikletochnoĭ kontsentratsii Ca2+ v izolirovannykh neĭronakh vinogradnoĭ ulitki.