Orientador: Tereza de Lourdes Scarpari Barrichello

Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba

Resumo: Ratos Wistar com 180 ~ 10 g de peso corporal receberam injeções diárias de NaF (0,06; 0,12 e 4,0 mgF/kg peso) ou
NaCl (controle), por via intraperitoneal, durante 45 dias. o plasma e o osso fêmur foram submetidos à determinação de fluor. Dosagens de fluor, cálcio, fosforo e eletroforese das...

Resumo: Ratos Wistar com 180 ~ 10 g de peso corporal receberam injeções diárias de NaF (0,06; 0,12 e 4,0 mgF/kg peso) ou
NaCl (controle), por via intraperitoneal, durante 45 dias. o plasma e o osso fêmur foram submetidos à determinação de fluor. Dosagens de fluor, cálcio, fosforo e eletroforese das proteínas do esmalte foram realizadas nas matrizes do esmalte jovem e maduro dos incisivos. Para estudo histo1ógico. dos ameloblastos, cortes semi-finos foram obtidos da região de secreção do esmalte dos incisivos inferiores. A dose diária de 4,0 mgF/kg peso resultou, no final de 45 dias, numa concentraçio elevada de fluor no sangue e nos ossos, sendo comprovadamente tóxica e fluorotica para todos os animais. O esmalte fluorótico apresentou retençio de amelogeninas na fase de maturação. As alterações observadas na morfologia dos ameloblastos secretores parecem estar relacionadas com os picos transitorios de flfiprno sangue, provocados pelas injeções intraperitoneais de NaF

Abstract: Three groups of 30 rats each received daily intraperitoneal injection, during 45 days, of 0,06, 0,12 and 4,0 mgF/~g of b.w., respectively. A fourth group used as control, received during the same period daily injections of 2,5% NaCl solution.
The amount of F was determined in blood plasma,...

Abstract: Three groups of 30 rats each received daily intraperitoneal injection, during 45 days, of 0,06, 0,12 and 4,0 mgF/~g of b.w., respectively. A fourth group used as control, received during the same period daily injections of 2,5% NaCl solution.
The amount of F was determined in blood plasma, bone (femur) and enamel. Only the 4,0 mg F group showed very high
levels of F and clear signs of fluoroses and toxicosis. The relation Ca/P in the enamel was in all groups similar to the control group.
Protein analysis, by SDS electrophoresis on polyacri lamide gels, of young and mature enamel showed that some amount of amelogenins were retained in the mature enamel of the 4,0 mg F group. The secretory ameloblasts of the lower incisors, of
2 animals of each group, were examined in 1 ~m-thick sections, stained with toluidine blue. All. experimental groups showed
some alterations in the ameloblasts being the vacuolization of cytoplasm and Tomes' processes the main ones. These morpho
logic changes seemed to be related not only to the amount of F given but also with the peak of F which occured in blood plasma at 7,5 and 15 min after the F injections in all experimental groups