Effects of vinblastine on calcium distribution pattern and Ca2+,Mg(2+)-adenosine triphosphatase in rat incisor maturation ameloblasts.
Vinblastine is known to affect secretory and transport functions of ameloblasts. The effects of vinblastine on distribution patterns of membrane-associated calcium and Ca2+,Mg(2+)-ATPase in maturation ameloblasts were investigated cytochemically. The potassium pyroantimonate (PPA) method was used for localizing calcium and a modified Wachstein-Meisel medium was used to localize Ca2+,Mg(2+)-ATPase. Ultrastructural changes induced by vinblastine included dislocated organelles and reduction or elimination of the ruffled border of the ameloblasts. Membrane-associated calcium pyroantimonate deposits were markedly reduced. The intensity of Ca2+,Mg(2+)-ATPase reaction product was also markedly reduced by vinblastine. Concomitant reduction of membrane-associated calcium and Ca2+,Mg(2+)-ATPase lends support to a role for maturation ameloblasts in control of a cyclic pattern of influx of calcium to mineralizing enamel.
Eisenmann
D R
DR
Department of Histology, College of Dentistry, University of Illinois, Chicago.
Salama
A H
AH
Zaki
A M
AM
D000565:Ameloblasts / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D000818:Animals; D000965:Antimony; D017301:Ca(2+) Mg(2+)-ATPase / Q000187:drug effects / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000187:drug effects / Q000378:metabolism*; D006651:Histocytochemistry; D007180:Incisor / Q000033:anatomy & histology*; D008566:Membranes / Q000737:chemistry; D008854:Microscopy, Electron; D051381:Rats; D011919:Rats, Inbred Strains; D014747:Vinblastine / Q000494:pharmacology*
C009002:potassium antimonate; D014747:Vinblastine; D000965:Antimony; D017301:Ca(2+) Mg(2+)-ATPase; D000252:Calcium-Transporting ATPases; D002118:Calcium