TY - JOUR
T1 - Effect of calcium antagonists, calcium channel blockers and calmodulin inhibitors on the growth and encystation of Entamoeba histolytica and E. invadens
AU - Makioka, A.
AU - Kumagai, M.
AU - Ohtomo, H.
AU - Kobayashi, S.
AU - Takeuchi, T.
N1 - Funding Information:
Acknowledgements The authors thank Dr. L. S. Diamond for the supply of E. histolytica and E. invadens and T. Okita for technical assistance. This work was supported by a Health Sciences Research Grant for Research on Emerging and Re-emerging Infectious Diseases from the Ministry of Health and Welfare of Japan.
PY - 2001
Y1 - 2001
N2 - The effects of calcium antagonists, calcium channel blockers, and calmodulin inhibitors on the growth of Entamoeba histolytica and the growth and encystation of Entamoeba invadens were examined. Calcium chelators ethyleneglycol bis (β-aminoethyl ether)-N,N'-tetraacetate (EGTA) and ethylene-diaminetetraacetate (EDTA) inhibited the growth of both Entamoeba and also the encystation of E. invadens in a dose-dependent manner, with EDTA being more effective than EGTA. A putative antagonist of intracellular calcium flux, 8-(N,N-diethylamino) octyl-3,4,5-trimethoxybenzoate (TMB-8) also inhibited both growth and encystation, with the E. histolytica being more sensitive than E. invadens, and with the growth of E. invadens being more sensitive than encystation. The slow Na+-Ca2+ channel blockers bepridil and verapamil inhibited both growth and encystation. Bepridil was more effective than verapamil. The calmodulin (CaM) inhibitors, W-7 (N-(6-aminohexyl)-chloro-1-naphtalene sulphonamide) and trifluoperazine (TFP), were also inhibitory for both the growth and encystation; TFP was more effective than W-7, and encystation was more sensitive than growth in E. invadens. These results indicate that extracellular calcium ions, amebic intracellular calcium flux, calcium channels, and a CaM-dependent process contribute to the growth and encystation of Entamoeba.
AB - The effects of calcium antagonists, calcium channel blockers, and calmodulin inhibitors on the growth of Entamoeba histolytica and the growth and encystation of Entamoeba invadens were examined. Calcium chelators ethyleneglycol bis (β-aminoethyl ether)-N,N'-tetraacetate (EGTA) and ethylene-diaminetetraacetate (EDTA) inhibited the growth of both Entamoeba and also the encystation of E. invadens in a dose-dependent manner, with EDTA being more effective than EGTA. A putative antagonist of intracellular calcium flux, 8-(N,N-diethylamino) octyl-3,4,5-trimethoxybenzoate (TMB-8) also inhibited both growth and encystation, with the E. histolytica being more sensitive than E. invadens, and with the growth of E. invadens being more sensitive than encystation. The slow Na+-Ca2+ channel blockers bepridil and verapamil inhibited both growth and encystation. Bepridil was more effective than verapamil. The calmodulin (CaM) inhibitors, W-7 (N-(6-aminohexyl)-chloro-1-naphtalene sulphonamide) and trifluoperazine (TFP), were also inhibitory for both the growth and encystation; TFP was more effective than W-7, and encystation was more sensitive than growth in E. invadens. These results indicate that extracellular calcium ions, amebic intracellular calcium flux, calcium channels, and a CaM-dependent process contribute to the growth and encystation of Entamoeba.
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U2 - 10.1007/s004360100453
DO - 10.1007/s004360100453
M3 - Article
C2 - 11688889
AN - SCOPUS:0034803026
SN - 0044-3255
VL - 87
SP - 833
EP - 837
JO - Zeitschrift fur Parasitenkunde
JF - Zeitschrift fur Parasitenkunde
IS - 10
ER -
