Effect of Thyroxine and Propylthiouracil in Ehrlich Ascitic Tumor Cells / Efecto de la Tiroxina y Propiltiouracilo en las Células del Tumor Ascítico de Ehrlich

The main purpose of this study was to investigate the effect of thyroxine and PTU in ascitic Ehrlich tumor cells. Tumor was implanted in 30 female mice distributed in three groups: treated with PTU, treated with thyroxine and control. Each group received an intraperitoneal injection of neoplastic cells, pre-incubated with sterile solutions of PTU, thyroxine and distilled water, respectively. On the fifth and seventh days after inoculation, animals received an intraperitoneal injection of the respective solutions. On the tenth day after inoculation, animals were sacrificed. Volume of ascitic liquid, number of neoplastic cells/ml and percentage of viable cells were determined. Ascitic liquid smears were carried out for tumor cytological evaluation. There was no difference among groups regarding ascitic liquid and as for the number and viability of tumor cells. However, cells under the effect of thyroxine presented significantly larger mean of nuclear diameter, size and number of nucleolus organizer regions. In this group, there was a predominance of clear, round cells with abundant eosinophilic and very vacuolated cytoplasm with little defined edges. Under the PTU effect, tumor cells were small with hyperchromatic nucleus and the same number of NORs as the control group. It was concluded that PTU and thyroxine have not changed the number and viability of cells after 10 days of tumor inoculation but they changed significantly cell characteristics. Whilst thyroxine increases cell size and the number of NORs of ascitic Ehrlich tumor cells, PTU causes an opposite effect.

El propósito principal de este estudio ha sido investigar el efecto de la tiroxina y del propiltiouracilo (PTU) en las células del tumor de Ehrlich. El tumor fue implantado en 30 ratones hembras distribuidas en tres grupos: tratado con PTU, tratado con tiroxina y control. Cada grupo recibió una inyección intraperitoneal de células neoplásicas, pre-incubadas con las soluciones estériles de PTU, tiroxina y agua, respectivamente. En el quinto y séptimo días después de la inoculación, los animales recibieron una inyección intraperitoneal de las soluciones respectivas. En el décimo día después de la inoculación, se sacrificaron los animales. Fueron determinados el volumen de líquido ascítico, el número de células/ml y el porcentaje de células viables. Además se realizaron frotis del líquido ascítico para la evaluación de la citología del tumor. No hubo ninguna diferencia entre los grupos con respecto al volumen del líquido ascítico y el número y viabilidad de las células del tumor. Sin embargo, las células bajo el efecto de la tiroxina presentaron una media significativamente superior del diámetro nuclear, tamaño y número de regiones organizadoras de nucleélos. En este grupo, había un predominio de células claras, redondas con citoplasma abundante, eosinofílico y vacuolado con poca definición de los bordes. Bajo el efecto del PTU, las células del tumor eran pequeñas con el núcleo hipercromático y el mismo número de NORs como el grupo control. Se concluye que el PTU y tiroxina no afectaron el número y viabilidad de las células después de 10 días de inoculación del tumor, pero sí cambiaron las características celulares. Aunque la tiroxina aumenta el tamaño celular y el número de NORs de las celulas del tumor de Ehrlich, PTU causa efectos opuestos.

Influência do hipotireoidismo induzido por propiltiouracil na mucosa gengival do rato / Influence of propilthiouracil-induced hypothyroidism on rat gingival mucosa / Influence of propilthiouracil-induced hypothyroidism on rat gingival mucosa

O objetivo foi verificar a influência da deficiência dos hormônios tireoideanos induzida por propiltiouracil (PTU) na mucosa gengival do rato, analisando bioquimicamente as proteínas totais, colágeno (hidroxiprolina) e população celular (DNA). Foram utilizados 50 ratos machos da cepa Sprague-Dawley, separados em 2 grupos: propiltiouracil (PTU) (10 mg/d i.p.), e controle (C), durante 10 semanas. As proteínas totais foram determinadas pelo método de Lowry, a hidroxiprolina pelo método de Newman e DNA pelo método de Burton. Observou-se diminuição das proteínas totais no grupo PTU (PTU= 41,23 ± 24,05; C= 63,36 ± 18,05); não houve diferença na hidroxiprolina e DNA (PTU= 2,18 ± 1,48; C= 2,29 ± 1,51) e (PTU= 0,33 ± 0,19; C= 0,46 ± 0,31). Conclui-se que o tratamento com PTU diminui o conteúdo de proteínas totais na mucosa gengival do rato, provavelmente pela diminuição da síntese protéica, sem alteração do colágeno e da população celular.

This work aimed at verifying the influence of propilthiouracil (PTU)-induced thyroid hormone deficiency on gingival mucosa of young male rats, measuring total protein concentration, collagen content and DNA concentration as indices of cellular population. Fifty Sprague-Dawley rats were used. The animals were grouped in: PTU-treated (i.p. 10 mg/d) and control rats (C). The experience was maintained for a period of 10 weeks. Total protein content of gingival mucosa tissue was determined by the Lowry method; hydroxyprolin rate, as prototype aminoacid of collagen, was determined using the Newman method, and DNA concentration was measured by Burton's methodology. The results showed decreased amounts of PTU-treated rats gingival total protein content (PTU= 41.23 ± 24.05 vs. C= 63.36 ± 18.05); no alterations were seen in hydroxyprolin concentration neither in DNA content of PTU treated rats, respectively (PTU= 2.18 ± 1.48 vs. C= 2.29 ± 1.51) and (PTU= 0.33 ± 0.19 vs. C= 0.46 ± 0.41). Thus, PTU treatment promotes a decrease in total protein content of rat gingival mucosa that may be interpreted as a decrease in protein synthesis induced by the hypothyroid condition, but with no alteration either in collagen or nucleic acid rates.