Laser terapêutico e células inflamatórias - parte 1: mastócitos* / Therapeutic laser and inflammatory cells - part 1: mast cells

O presente estudo avaliou a quantidade de mastócitos após irradiação do laser não cirúrgico λ685 nm. Dezoito ratos machos, linhagem Wistar (250 a 300 gramas), nos quais foram realizadas feridas cirúrgicas padronizadas, foram distribuídos em seis grupos, três experimentais (com quatro ratos) e três controles (com dois ratos). Os grupos experimentais foram irradiados em quatro pontos perilesionais equidistantes (0,5 J/cm², 35 mW, 35 Hz e 17 segundos). Os grupos-controles não foram irradiados. Os animais foram mortos 6, 12 e 24 horas após a irradiação, sendo obtidas peças que seguiram para processamento laboratorial de rotina. O estudo das lâminas foi realizado por meio da contagem absoluta dos mastócitos pelo método esteriológico. Os resultados obtidos demonstraram que, nas primeiras 6 e 12 horas, após a irradiação laser, existe uma diminuição no número total de mastócitos, estatisticamente significante, quando comparados aos grupos controles, porém, após 24 horas, não existem diferenças no número de mastócitos entre os grupos experimental e controle. Baseados nos resultados obtidos com o protocolo de aplicação da luz laser utilizado, para esse modelo animal, pôde-se concluir que a luz laser é capaz de diminuir o número total de mastócitos após uma única irradiação.

This study measured the variation in the total number of mast cells after low level laser therapy (λ= 685 nm) using a stereological method. Eighteen male Wistar rats (250 to 300 grams) with standardized surgical wounds were randomly distributed into 6 groups - 3 study groups with 4 rats each, and 3 control groups with 2 rats each. In the study groups, four equidistant spots around the standardized wound were irradiated (0.5 J/cm², 35 mW, 35 Hz, 17 seconds). The control groups were not irradiated. The animals were killed at 6, 12 and 24 hours after laser therapy. Biological specimens were harvested and routinely processed; slides were prepared and stained with toluidine blue. The total number of mast cells was counted using the stereological method. A statistically significant decrease in the total number of mast cells was observed at 6 and 12 hours after irradiation. However, there was nodifference in the number of mast cells between study and control groups at 24 hours. Our results showed that one single irradiation with laser light reduced the total number of mast cells in the animal model used in this study.

Laser terapêutico e células inflamatórias - parte 2: neutrófilos* / Therapeutic laser and inflammatory cells - part 2: neutrophils

O objetivo deste trabalho foi estudar a intensidade do infiltrado inflamatório agudo, presente em tecido conjuntivo perilesional do dorso de ratos submetidos à irradiação laser de baixa potência (λ 685 nm) após uma única aplicação. Foram utilizados dezoito ratos machos, linhagem Wistar, de 250 a 300 gramas, nos quais foram realizadas feridas cirúrgicas padronizadas. A amostra foi constituída de seis grupos, três experimentais e três controles, compostos por quatro e dois ratos, cada grupo, respectivamente. Os grupos experimentais foram irradiados em quatro pontos perilesionais equidistantes, com uma única dose de 0,5J/cm² por ponto, com potência de 35 mW, frequência de 35 pulsos por segundo e tempo de aplicação por ponto de 17 s. Os grupos-controles não foram irradiados. Os animais foram mortos 6, 12 e 24 horas após a irradiação, sendo obtidas peças que seguiram para processamento laboratorial de rotina. O estudo das lâminas foi realizado através da descrição e contagem absoluta dos granulócitos pelo método esteriológico. Os resultados obtidos demonstraram que há uma diminuição no número total de granulócitos, não significante estatisticamente (p≥0,05), quando comparados aos grupos controles. Concluiu-se que a luz laser é capaz de diminuir a intensidade do infiltrado inflamatório após uma única irradiação.

The aim of this work was study the intensity of acute inflammatory infiltrate inconnective tissue after low level laser therapy (λ = 685 nm) irradiation. Eighteen maleWistar rats (250 to 300 grams) with standardized surgical wounds were randomlydistributed into 6 groups - 3 study groups with 4 rats each, and 3 control groups with2 rats each. In the study groups, four equidistant spots around the standardizedwound were irradiated (0.5 J/ cm², 35 mW, 35 Hz, 17 seconds). The control groupswere not irradiated. The animals were killed at 6, 12 and 24 hours after laser therapy.Biological specimens were harvested and routinely processed. The total number of granulocyteswascounted using the stereological method. A non-statistically significant decrease in thetotal number granulocytes was observed in the all study groups. Our results showedthat one single irradiation with laser light reduced the total number of graunulocytesin the animal model used in this study.

Simplified stereological evaluation of renal morphology after unilateral ureteral obstruction.

OBJECTIVE AND METHODS: This study established a simple stereological method to obtain quantitative information about two- or three-dimensional structures based on observations from kidney sections in the unilateral ureteral obstruction(UUO) model. RESULTS: Tubulointerstitial area(TA) and TA/the area of a rectangular field(RA) were raised gradually, but significantly, in the obstructed kidney from 1 to 3months post-ligation in comparison to the sham kidney of sham-operated rats(SOR). On the contrary, glomerular area(GA) and glomerular volume(GV) were decreased progressively over time, but significantly, in the obstructed kidney from 3weeks to 3months post-ligation compared to the sham kidney of SOR. UUO caused a progressive decline of TA and TA/RA in the contralateral kidney. More specifically, there were significant decreases in TA at 1,2,3months post-ligation, while in TA/RA only at 3months post-ligation in comparison to the right kidney of SOR. In contrast, GA and GV enhanced in a time-dependent manner in the contralateral kidney, in which the difference in GA reached significance only at 3months post-ligation, whereas the difference in GV reached significance from 1 to 3months post-ligation when comparing with the right kidney of SOR. CONCLUSIONS: Our results confirmed two typical features of obstructive nephropathy, including widen interstitial space and glomerular atrophy in the obstructed kidney, and compensatory growth of the contralateral kidney.

Effects of infantile repeated hyperglycemia on neuronal density of hippocampus and pentylentetrazol induced convulsions in male wistar rats.

OBJECTIVE(S): High blood glucose induces molecular, cellular, morphological and behavioral changes in the brain. Metabolic disturbances, contribute to the hippocampus injury and development of partial focal seizures. The aim of this study was to investigate the effects of infantile repeated hyperglycemia on neuronal density of hippocampal CA3 region in newborn Wistar male rats and its effect on chemoconvulsant pentylentetrazol (PTZ) induced generalized seizures in adults. MATERIALS AND METHODS: Ten days old male Wistar rats were randomly divided into 2 groups (n=20 for each): hyperglycemic and control. Hyperglycemia was induced by intraperitoneal injections of 2 g/kg dextrose solution, twice a day, for 2 weeks. Control animals received saline solution in the same manner. Blood glucose was regularly measured. After that, the brains of rats from each group (n=10) were removed for histological analysis of the CA3 region of hippocampus by stereological method. Other animals (n=10) were kept to grow older. Afterwards, seizure was induced in hyperglycemic and control adult rats, by an intraperitoneal injection of 45 mg/kg PTZ solution and then latency of convulsions onset and severity of seizures for each group were recorded. RESULTS: RESULTS showed that hippocampal neuronal density decreased significantly and susceptibility to PTZ induced convulsions increased in experimental animals. CONCLUSION: The result determined that repeated increments in daily blood sugar levels in infantile period may damage neuronal structures of hippocampus and also make adults more susceptible to PTZ induced convulsions in adulthood period.