Possible Interaction: Neomycin and Calcium Supplement

“ Neomycin displayed higher blockade with a half inhibition in the nanomolar range at low calcium concentration and in the micromolar range in physiological calcium concentration but still exerted blockade below the concentration used in the clinic.”

“In this study, we found that the store‐operated Ca2+ entry was inhibited by neomycin , an aminoglycoside that strongly binds phosphatidylinositol 4,5‐bisphosphate (PtdIns(4,5)P2).”

“Patch clamp recordings revealed that neomycin blocked the CRAC currents reconstituted by co‐expression of Orai1 and Stim1 in HEK293 cells.”

“This result suggests that PtdIns(4,5)P2 is not required for CRAC channel activity, and thereby, neomycin inhibits CRAC channels in a manner that is independent of neomycin–PtdIns(4,5)P2 binding.”

“ Neomycin , an aminoglycoside polycation, inhibited both the “transient” (ICa,t) and the “slowly-inactivating” (ICa,s) Ca currents in a dose-dependent manner (100–1,000 μM).”

“Consistently, neomycin time-dependently diminished the calcium current amplitude letting the channel exhibit the hallmarks of the voltage-independent regulation.”

“In the presence of U73122 or neomycin there was a decrease in calcium with inhibition factors (I.F.) of 0.39 ± 0.09 and 0.37 ± 0.08, respectively, whereas rottlerin abolished the REV5901-induced [Ca2+]i rise.”

“ Neomycin (0.5 mmol l–1) blocked inositol 1,4,5-trisphosphate-, caffeine-, and Ca2+ -induced Ca2+ release.”

“Whereas ryanodine and caffeine had no effect, both neomycin and thapsigargin significantly decreased the Ca2+i response to flow, suggesting a role for Ca2+ store release, possibly through an inositol 1,4,5‐trisphosphate (IP3)‐dependent mechanism.”

“Moreover, in synaptosomes permeabilized with Staphylococcus aureus α‐toxin, PLD activation induced by calcium was abolished by neomycin , a PIP2 chelator.”

“A portion of the dendritic release is calcium independent but can be inhibited partially by neomycin , which might suggest a role for inositol 4,5‐bisphosphate breakdown products.”

“… Ca2+o from 1.1 to 5 mM reversibly reduced the activity of the 70-pS K+ … to 16 +/- 2% of the control value within 300 s. In addition, 50 microM neomycin mimicked the effect of an increase in Ca2+o … cell-attached patches and completely inhibited channel activity.”