Effect of hydrogen peroxide on neuron sensitivity to acetylcholine.
The dose-dependent effect of hydrogen peroxide on snail neuromembrane chemosensitivity was studied by means of standard voltage-clamp method. Short-term exposure (7 min) of neurons to H(2)O(2) (10(-11)-10(-4) M) caused dose-dependent depression of Acetylcholine (Ach)-induced ionic currents in the membrane. The H(2)O(2)-induced depression of Ach-sensitivity of membrane was more pronounced in K(+)-free solution than in normal physiological solution and it disappeared in cold medium (5 degrees C). The H(2)O(2) (10(-11)-10(-4) M) decreased membrane electrical conductivity and cell volume. The dose-dependent decrease in Ach-sensitivity of the snail neuromembrane by H(2)O(2) may be due to a decrease in the number of functionally active membrane receptors caused by a decrease in membrane active surface. H(2)O(2)-induced decrease in Ach-sensitivity has a metabolic but Na(+)-K(+) pump independent character, the nature of which is the subject for current investigation.
Hunanyan
Arsen
A
UNESCO Chair--Life Sciences International Postgraduate Educational Center, Yerevan, Armenia.
Ayrapetyan
Sinerik
S
D000109:Acetylcholine / Q000008:administration & dosage*; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004357:Drug Synergism; D006861:Hydrogen Peroxide / Q000008:administration & dosage*; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D012908:Snails
D006861:Hydrogen Peroxide; D000109:Acetylcholine