RESUMO A função e proteção das glândulas paratireoidianas é um tópico de pesquisa cada vez mais popular. Coelhos brancos da Nova Zelândia são o modelo animal mais comumente usada para isquemia da paratireóide. Porém, informação sobre a vasculatura de suas glândulas paratireóides é limitada. Foram usados 94 coelhos brancos da Nova Zelândia saudáveis, com 3-4 meses de idade, 2-3kg de peso, para exploração das glândulas paratireóides, que foram coradas com hematoxilina e eosina (HE) após a remoção. Os seguintes tipos foram classificados de acordo com a relação entre a posição da glândula paratireoidiana inferior e a tireoide: Tipo A, Tipo Próximo, Tipo B e Tipo Distante. Houve 188 casos, 4 em que as glândulas paratireoidianas inferiores estavam localizadas próximas ao lado dorsal da tireoide (2.13%), 8 onde as glândulas paratireoidianas inferiores estavam localizadas superiores ao polo superior da tireoide (4.26%), 20 onde as glândulas paratireoidianas inferiores estavam localizadas paralelo à tireoide (10.64%) e 155 casos em que as glândulas paratireoidianas inferiores estavam localizadas inferiores ao polo inferior da tireoide (82.45%). A identificação da localização e a classificação da vasculatura das glândulas paratireóides em coelhos brancos da Nova Zelândia fornecerão um modelo anatômico para auxiliar em pesquisas futuras.

ABSTRACT The function and protection of the parathyroid glands are increasingly popular research topics. New Zealand white rabbits are the most commonly used animal model of parathyroid ischemia. However, information on the vasculature of their parathyroid glands is limited. We used 94 healthy New Zealand white rabbits, 3-4 months of age and 2-3kg in weight, for exploration of the parathyroid glands, which were stained using hematoxylin and eosin (HE) after removal. The following types were classified according to the relationship between the position of the inferior parathyroid gland and the thyroid: Type A, Close Type, Type B, and Distant Type. There were 188 cases, 4 where the inferior parathyroid glands were located near the dorsal side of thyroid (2.13%), 8 where the inferior parathyroid glands were located superior to the upper pole of the thyroid (4.26%), 20 where the inferior parathyroid glands were located parallel to the thyroid (10.64%), and 155 cases where the inferior parathyroid glands were located inferior to the lower pole of thyroid (82.45%). Identifying the location and classifying the vasculature of the parathyroid glands in New Zealand white rabbits will provide an anatomical model to assist in future research.

Lipopolysaccharide exerts many effects on many cell lines, including cytokine secretion, and cell apoptosis and necrosis. We investigated the in vitro effects of lipopolysaccharide on apoptosis of cultured human dental pulp cells and the expression of Bcl-2 and Bax. Dental pulp cells showed morphologies typical of apoptosis after exposure to lipopolysaccharide. Flow cytometry showed that the rate of apoptosis of human dental pulp cells increased with increasing lipopolysaccharide concentration. Compared with controls, lipopolysaccharide promoted pulp cell apoptosis (P < 0.05) from 0.1 to 100 μg/mL but not at 0.01 μg/mL. Cell apoptosis was statistically higher after exposure to lipopolysaccharide for 3 days compared with 1 day, but no difference was observed between 3 and 5 days. Immunohistochemistry showed that expression of Bax and Bcl-2 was enhanced by lipopolysaccharide at high concentrations, but no evident expression was observed at low concentrations (0.01 and 0.1 μg/mL) or in the control groups. In conclusion, lipopolysaccharide induced dental pulp cell apoptosis in a dose-dependent manner, but apoptosis did not increase with treatment duration. The expression of the apoptosis regulatory proteins Bax and Bcl-2 was also up-regulated in pulp cells after exposure to a high concentration of lipopolysaccharide.