Djanira Aparecida da Luz Veronez

Orofacial sensory changes after streptozotocin-induced diabetes in rats

Peripheral neuropathy is a common complication of diabetes and is often accompanied by episodes of pain. There is evidence that diabetic neuropathy may affect the trigeminal nerve, altering the transmission of orofacial sensory information. Structural changes in the trigeminal ganglia may be involved in the development of these sensory alterations. Herein, we evaluate the development of orofacial sensory changes after streptozotocin-induced diabetes in rats, and their sensitivity to pregabalin and morphine treatments. Furthermore, stereological analysis of the trigeminal ganglia was performed. Diabetic rats showed similar responses to 1% formalin applied into the upper lip compared to normoglycemic rats on weeks 1, 2 and 4 after streptozotocin. Additionally, there was no difference in the facial mechanical threshold of normoglycemic and diabetic rats, on weeks 1 up to 5 after streptozotocin, while the paw mechanical threshold of diabetic rats was significantly reduced. In contrast, diabetic rats developed long-lasting orofacial heat and cold hyperalgesia. Moreover, stereological analyses revealed significant neuronal loss in the trigeminal ganglia of diabetic compared to normoglycemic rats. Pregabalin treatment (30mg/kg, p.o.) of diabetic rats resulted in marked and prolonged (up to 6h) reduction of heat and cold orofacial hyperalgesia. Likewise, morphine treatment (2.5mg/kg, s.c.) abolished orofacial heat and cold hyperalgesia, but its effect was significant only up to 1h after the administration. In conclusion, the results of the present study demonstrated that streptozotocin-treated rats developed long-lasting orofacial heat and cold hyperalgesia, which is more amenable to reduction by pregabalin than morphine.

Numeric and volumetric changes in Leydig cells during aging of rats

PURPOSE To analyze the effects of aging in rats on the nuclear volume, cytoplasmic volume, and total volume of Leydig cells, as well as their number. METHODS Seventy-two Wistar rats were divided into six subgroups of 12 rats, which underwent right orchiectomy at 3, 6, 9, 12, 18, and 24 months of age. The weight and volume of the resected testicles were assessed. A stereological study of Leydig cells was conducted, which included measurements of cell number and nuclear, cytoplasmic, and total cell volumes. RESULTS The weight and volume of the resected testicles showed reductions with age. Only the subgroup composed of 24-month old rats showed a decrease in the nuclear volume of Leydig cells. Significant reductions in the cytoplasmic volume and total volume of Leydig cells were observed in 18- and 24-month old rats. The number of Leydig cells did not vary significantly with age. CONCLUSIONS Aging in rats resulted in reduction of the nuclear, cytoplasmic, and total cell volumes of Leydig cells. There was no change in the total number of these cells during aging.

Analysis of the histology of the scar bladder and biochemical parameters of rats with a solitary kidney undergoing immunosuppression with tacrolimus.

PURPOSE To evaluate bladder histology in healing and biochemical analysis of rats with single kidney in ischemia/reperfusion, treated with tacrolimus. METHODS Fifty rats randomized into five groups. Three rats died in surgery, 47 rats divided in groups: Control (non-operated, n=10), Sham (operated without drugs, n=8), T1 (operated + tacrolimus 1mg/kg, n=10), T2 (operated + tacrolimus 0.1 mg/kg, n=10), T3 (operated + tacrolimus 10mg/kg, n=9). The surgery was: laparotomy, right nephrectomy, left kidney ischemia/reperfusion, cystotomy followed by bladder suture. After that, rats were submited to gavage daily (Control and Sham with saline solution. T1, T2, T3 with tacrolimus in doses already mentioned). On the 14th day, after death induction, cystectomy was performed and bladder was histologicaly analysed. The serum urea, creatinine and tacrolimus were analysed too. RESULTS There was difference in serum tacrolimus in T3 compared to the other groups (p<0.05). There was higher doses of creatinine in T3 group and higher urea in groups with tacrolimus. There were significant differences among all histologic variables comparing groups with and without tacrolimus (p<0.05). CONCLUSION Tacrolimus associated with ischemia/reperfusion is nephrotoxic, suppresses inflammation and seems to delay the healing bladder.

Quantitative analysis of the renal aging in rats. Stereological study

PURPOSE To evaluate the renal function and the renal histological alterations through the stereology and morphometrics in rats submitted to the natural process of aging. METHODS Seventy two Wistar rats, divided in six groups. Each group was sacrificed in a different age: 3, 6, 9, 12, 18 and 24 months. It was performed right nephrectomy, stereological and morphometric analysis of the renal tissue (renal volume and weight, density of volume (Vv[glom]) and numerical density (Nv[glom]) of the renal glomeruli and average glomerular volume (Vol[glom])) and also it was evaluated the renal function for the dosage of serum creatinine and urea. RESULTS There was significant decrease of the renal function in the oldest rats. The renal volume presented gradual increase during the development of the rats with the biggest values registered in the group of animals at 12 months of age and significant progressive decrease in older animals. Vv[glom] presented statistically significant gradual reduction between the groups and the Nv[glom] also decreased significantly. CONCLUSIONS The renal function proved to be inferior in senile rats when compared to the young rats. The morphometric and stereological analysis evidenced renal atrophy, gradual reduction of the volume density and numerical density of the renal glomeruli associated to the aging process.

Continuous therapeutic ultrasound in the healing process in rat skin

Introduction : The therapeutic ultrasound is one of the main resources utilized on physical therapy to stimulate the healing due its thermal and mechanic effects. However, your application still not properly standardized. Objective :To analyze the presence of the collagens types I and III stimulated by the ultrasonic wave in continuous mode at the cutaneous injury local for first intention. Material and methods : It was utilized 90 Wistar rats, young adults, with average weight of 230g, divided in 3 groups of 30 animals: control group, treated with ultrasound off; group 1, treated with ultrasound 0.5 W/cm2 and group 2, treated with ultrasound 2.0 W/cm2. Each group was subdivided in 3 subgroups according with the healing phases, 3, 7 and 21 days of consecutive therapeutic sessions. The ultrasound therapy began 24 hours after the termination of the surgical act, at the dorsal region, applying frequency of 3 MHz and intensities 0.5 W/cm2 and 2.0 W/cm2 during 5 minutes under sliding technique. Later, the animals were sacrificed according to the healing phases for removal of incisional area and histological analyses. Conclusions : The results allowed conclude that the continuous mode of therapeutic ultrasound in the intensities 0.5 W/cm2 and 2.0 W/cm2promoted stimulus to formation of collagens types I and III in the lesion area for first intention.