Metabolic and ultrastructural renal changes in adult Wistar rats fed by a cafeteria diet

Purpose: To evaluate, by quantitative and qualitative methods, the glomerular ultrastructure in Wistar rats fed a cafeteria diet. Methods: Male Wistar rats were divided into two groups at 21 days of age: control (C, n = 10) and cafeteria diet (CAF, n = 8). The animals were followed up until 5 months of age, followed by euthanasia. The blood, kidneys, and fat deposits­­epididymal, retroperitoneal, and subcutaneous­­were extracted and analyzed. Data were analyzed by Student's t test, and p < 0.05 was considered statistically significant. Results: The cafeteria diet promoted glucose intolerance, hyperglycemia (p < 0.0001), and deposition of retroperitoneal fat (p < 0.005). Scanning electron microscopy revealed that the length of the foot process was similar in both groups. The quantitative analyses by transmission electron microscopy revealed that the cafeteria diet reduced the thickness of the glomerular basement membrane (p < 0.05). Conclusions: The intake of lipids and simple carbohydrates were found to be associated with alteration in the glomerular ultrastructure. However, more studies are needed to evaluate not only the effects of high-protein and high-fat diets on components of the glomerular filtration barrier, but also renal physiology.

Effects of chronic restraint stress in the prostate of prepubertal and adult rats

Purpose: To investigate the effects of chronic stress in the prostate of prepubertal and adult rats. Methods: Thirty-two male rats were assigned into four groups depending on the type of treatment (control or stressed) and the age at which stress was initiated (prepubertal or adult). Restraint stress stimuli were applied for six weeks. Stressed prepubertal and adult rats evaluated immediately after the last stress stimuli were named SP and SA groups, respectively. Age-matched rats were used as control groups (CP and CA). At the end of the experiment, the rats were euthanized, and prostate morphological parameters were evaluated and statistically compared. Results: Application of stress stimuli to the SP group resulted in reduced body weight, but no prostate morphological modification was noted. The SA group showed reduced testosterone level and prostatic epithelium surface density, in comparison to CA group. Further, the prostatic lumen surface density was increased in adult stressed animals, in comparison to adult controls. Conclusions: The stress stimuli promoted changes in hormonal and morphological parameters in the prostate of adult stressed rats. Prepubertal stressed animals did not presented modifications of prostate morphology.

Histomorphometric comparison of the corpus cavernosum of rats submitted to euthanasia with ketamine and xylazine or isoflurane

ABSTRACT Purpose: To compare the penile histoarchitecture of rats euthanized with isoflurane or with ketamine and xylazine. Methods: Fourteen male rats were divided into two groups: ISO, with animals euthanized with isoflurane; and K+X, with animals euthanized with ketamine (150 mg/kg) associated with xylazine (15 mg/kg). Immediately after the death, the penises were dissected, fixed in a 4% buffered formalin solution, and processed for histomorphometric analysis. The surface densities (Sv) of the corpus cavernosum structures (connective tissue, smooth muscle, sinusoidal space, and elastic fibers) were evaluated using Image J software. The distribution of collagen types I and III was qualitatively assessed. Statistical analyses were performed using the Student's t test for data comparison, considering it statistically significant when p < 0.05. Results: Regarding the Sv of connective tissue, smooth muscle and sinusoidal space, there were no differences between animals in both groups. On the other hand, the animals euthanized with the association of ketamine and xylazine showed the Sv of elastic fibers 24.8% higher in relation to animals euthanized with isoflurane. Conclusions: The euthanasia method affected one of the morphological parameters of the rat penises. The choice of euthanasia method must be standardized to reduce bias and to obtain reliable and reproducible results.

Expression of stromal elements of prostatic adenocarcinoma in different gleason scores.

PURPOSE: To quantify and compare the expression of stromal elements in prostate adenocarcinoma of different Gleason scores with non-tumor area (control). METHODS: We obtained 132 specimens from samples of prostate peripheral and transition zone. We analyzed the following elements of the extracellular matrix: collagen fibers, elastic system, smooth muscle fibers and blood vessels. The tumor area and non-tumor area (control) of the TMA (tissue microarray) were photographed and analyzed using the ImageJ software. RESULTS: The comparison between the tumor area and the non-tumor area showed significant differences between stromal prostate elements. There was an increase of collagen fibers in the tumor area, mainly in Gleason 7. Elastic system fibers showed similar result, also from the Gleason 7. Blood vessels showed a significant increase occurred in all analyzed groups. The muscle fibers exhibited a different behavior, with a decrease in relation to the tumor area. CONCLUSIONS: There is a significant difference between the extracellular matrix in prostate cancer compared to the non-tumor area (control) especially in Gleason 7. Important modifications of the prostatic stromal elements strongly correlate with different Gleason scores and can contribute to predict the pathological staging of prostate cancer.

Expression of stromal elements of prostatic adenocarcinoma in different gleason scores

Abstract Purpose: To quantify and compare the expression of stromal elements in prostate adenocarcinoma of different Gleason scores with non-tumor area (control). Methods: We obtained 132 specimens from samples of prostate peripheral and transition zone. We analyzed the following elements of the extracellular matrix: collagen fibers, elastic system, smooth muscle fibers and blood vessels. The tumor area and non-tumor area (control) of the TMA (tissue microarray) were photographed and analyzed using the ImageJ software. Results: The comparison between the tumor area and the non-tumor area showed significant differences between stromal prostate elements. There was an increase of collagen fibers in the tumor area, mainly in Gleason 7. Elastic system fibers showed similar result, also from the Gleason 7. Blood vessels showed a significant increase occurred in all analyzed groups. The muscle fibers exhibited a different behavior, with a decrease in relation to the tumor area. Conclusions: There is a significant difference between the extracellular matrix in prostate cancer compared to the non-tumor area (control) especially in Gleason 7. Important modifications of the prostatic stromal elements strongly correlate with different Gleason scores and can contribute to predict the pathological staging of prostate cancer.

Different sample preparation methods for glomerular morphological evaluation: to coat or not to coat? / Diferentes métodos de preparación de muestras para la evaluación morfológica glomerular ¿recubrir o no recubrir?

The renal glomerulus is coated by fenestrated endothelial cells and externally covered by specialized epithelial cells, known as podocytes. Scanning electron microscopy becomes an important and effective tool for its studies. Normally, samples destined for scanning microscopy are covered with a thin metallic layer. However, this step can be dispensed for some analyzes. We aimed to compare coated and uncoated samples for evaluation of the glomerular morphology of the Wistar rat kidney. Cortical region of the kidney of the 5month-old male Wistar rats were used. The fragments followed the routine procedure for scanning electron microscopy processing. Half of 10 fragments were coated with palladium gold and the remaining were not coated. Auriga Compact FIB - SEM scanning electron microscope was used to observe the samples. Different increases and voltages was evaluated. For the uncoated samples, when using voltages of 2 KV (or higher) a great charging was observed, impairing the use of such voltage. Thus, these samples were always observed under voltage of 0.5 KV. On the other hand, in the coated samples, the use of 2 KV was adequate. Almost as a consequence, in the coated samples, the podocyte structures were better characterized, generating better images. Inversely, in the uncoated samples, it was possible to visualize the desired structures and to detect the morphological characteristics of these. The results showed that it is possible to use kidney samples without previous coating to evaluate the glomerular morphology at the ultrastructural level, serving as a tool in the study of pathologies.

El glomérulo renal está recubierto por células endoteliales fenestradas y cubierto externamente por células epiteliales especializadas, conocidas como podocitos. La microscopía electrónica de barrido se convierte en una herramienta importante y efectiva para sus estudios. Normalmente, las muestras destinadas a microscopía de barrido se cubren con una capa metálica delgada. Sin embargo, este paso se puede dispensar para algunos análisis. El objetivo fue comparar muestras recubiertas y no recubiertas para evaluar la morfología glomerular del riñón de rata Wistar. Se utilizó la región cortical del riñón de ratas Wistar macho de 5 meses de edad. Se realizó el procedimiento de rutina para el procesamiento de microscopía electrónica de barrido. La mitad de 10 fragmentos se recubrieron con oro paladio y los restantes no se recubrieron. Se utilizó un microscopio electrónico de barrido SEM Auriga Compact FIB para observar las muestras. Se evaluaron diferentes aumentos y voltajes. Para las muestras no recubiertas, al usar voltajes de 2 KV (o más) se observó una gran carga, impidiendo el uso de dicho voltaje. Por lo tanto, estas muestras siempre se observaron a bajo voltaje de 0,5 KV. Por otro lado, en las muestras recubiertas, el uso de 2 KV fue adecuado. Como consecuencia, en las muestras recubiertas, las estructuras de los podocitos se caracterizaron mejor, generando mejores imágenes. Inversamente, en las muestras no recubiertas, fue posible visualizar las estructuras deseadas y detectar las características morfológicas de éstas. Los resultados mostraron que es posible utilizar muestras de riñón sin recubrimiento previo para evaluar la morfología glomerular a nivel ultraestructural, que sirve como una herramienta en el estudio de patologías.

The relationship between renal warm ischemia time and glomerular loss. An experimental study in a pig model.

PURPOSE:: To investigate the glomerular number after different warm ischemia times. METHODS:: Thirty two pigs were assigned into four groups. Three groups (G10, G20, and G30) were treated with 10, 20, and 30 minutes of left renal warm ischemia. The sham group underwent the same surgery without renal ischemia. The animals were euthanized after 3 weeks, and the kidneys were collected. Right kidneys were used as controls. The kidney weight, volume, cortical-medullar ratio, glomerular volumetric density, volume-weighted mean glomerular volume, and the total number of glomeruli per kidney were obtained. Serum creatinine levels were assessed pre and postoperatively. RESULTS:: Serum creatinine levels did not differ among the groups. All parameters were similar for the sham, G10, and G20 groups upon comparison of the right and left organs. The G30 group pigs' left kidneys had lower weight, volume, and cortical-medullar ratio and 24.6% less glomeruli compared to the right kidney. A negative correlation was found between warm ischemia time and glomerular number. CONCLUSIONS:: About one quarter of glomeruli was lost after 30 minutes of renal warm ischemia. No glomeruli loss was detected before 20 minutes of warm ischemia. However, progressive glomerular loss was associated with increasing warm ischemia time.

The relationship between renal warm ischemia time and glomerular loss. An experimental study in a pig model

Abstract Purpose: To investigate the glomerular number after different warm ischemia times. Methods: Thirty two pigs were assigned into four groups. Three groups (G10, G20, and G30) were treated with 10, 20, and 30 minutes of left renal warm ischemia. The sham group underwent the same surgery without renal ischemia. The animals were euthanized after 3 weeks, and the kidneys were collected. Right kidneys were used as controls. The kidney weight, volume, cortical-medullar ratio, glomerular volumetric density, volume-weighted mean glomerular volume, and the total number of glomeruli per kidney were obtained. Serum creatinine levels were assessed pre and postoperatively. Results: Serum creatinine levels did not differ among the groups. All parameters were similar for the sham, G10, and G20 groups upon comparison of the right and left organs. The G30 group pigs' left kidneys had lower weight, volume, and cortical-medullar ratio and 24.6% less glomeruli compared to the right kidney. A negative correlation was found between warm ischemia time and glomerular number. Conclusions: About one quarter of glomeruli was lost after 30 minutes of renal warm ischemia. No glomeruli loss was detected before 20 minutes of warm ischemia. However, progressive glomerular loss was associated with increasing warm ischemia time.

Glomerular Loss After Renal Radiofrequency Ablation Are Comparable to 30 Minutes of Warm Ischemia.

PURPOSE: To compare, with stereological methods, the glomerular loss in kidneys submitted to radiofrequency ablation (RFA) or warm ischemia. MATERIALS AND METHODS: Twenty-six male pigs were divided into three groups. Eight animals were allocated in the sham group, which was submitted to laparoscopic dissection of the left renal hilum, without renal ischemia. Eight animals were allocated in the ischemia group, which had the left renal hilum clamped for 30 minutes under laparoscopic access. Ten animals were submitted to RFA of the left kidney lower pole, under laparoscopic visualization. Animals were euthanized 21 days after surgery, when kidneys were collected. Fragments of the upper pole of the left kidney were processed for morphometric analysis. Right kidney was used as self-controls for each animal. Glomerular volumetric density (Vv[glom]); volume-weighted glomerular volume (VWGV); and glomerular density were quantified by stereological methods and compared by Student's t-test and one-way-analysis of variance with Dunnett's post-test. RESULTS: Three animals in the RFA group developed postoperative complications (Urinoma/Hydronephrosis) and were excluded from the analysis. No difference was found among the kidneys submitted to RFA and warm ischemia for all parameters. However, these kidneys showed lower Vv[glom] and glomerular density when compared to its self-controls (right kidneys), and when compared to sham-operated animals (p < 0.05). No difference was observed in regards to VWGV among the groups. CONCLUSION: RFA in pigs determines a significant reduction of glomerular density in the remaining parenchyma. This alteration was comparable to that observed in kidneys submitted to 30 minutes of warm ischemia.

Glomerular loss after arteriovenous and arterial clamping for renal warm ischemia in a swine model.

PURPOSE:: To evaluate the glomerular loss after arteriovenous or arterial warm ischemia in a swine model. METHODS:: Twenty four pigs were divided into Group Sham (submitted to all surgical steps except the renal ischemia), Group AV (submitted to 30 minutes of warm ischemia by arteriovenous clamping of left kidney vessels), and Group A (submitted to 30 minutes of ischemia by arterial clamping). Right kidneys were used as controls. Weigh, volume, cortical volume, glomerular volumetric density (Vv[Glom]), volume-weighted glomerular volume (VWGV), and the total number of glomeruli were measured for each organ. RESULTS:: Group AV showed a 24.5% reduction in its left kidney Vv[Glom] and a 25.4% reduction in the VWGV, when compared to the right kidney. Reductions were also observed when compared to kidneys of sham group. There was a reduction of 19.2% in the total number of glomeruli in AV kidneys. No difference was observed in any parameters analyzed on the left kidneys from group A. CONCLUSIONS:: Renal warm ischemia of 30 minutes by arterial clamping did not caused significant glomerular damage, but arteriovenous clamping caused significant glomerular loss in a swine model. Clamping only the renal artery should be considered to minimize renal injury after partial nephrectomies.

Nutritional supplementation with arginine protects radiation-induced effects. An experimental study.

PURPOSE:: To investigate the protective effect of L-arginine on the prostate (nonneoplasic) of rats with radiation-induced injury. METHODS:: Twenty-nine Wistar rats, male adult, allocated into three groups: Control group (C) was not exposed to irradiation (n=10); Radiated group (R) had undergone pelvic irradiation (n=10); Supplemented and radiated group (R+S) had undergone pelvic irradiation plus L-arginine supplementation (n=9). The animals were observed for signs of toxicity. After euthanization, the prostate was dissected under magnification and stained by hematoxylin and eosin to study acinar structures and stained with Picrosirius red for collagen analysis. RESULTS:: After radiation exposure, all animals presented diarrhea, but supplementation with L-arginine reduced this effect. The weight gain in the R+S group was significantly higher than in the C and R groups. In the R+S group the collagen density and the prostate acinar area was similar to the R and C groups. Epithelial height was significantly reduced in group R compared with group C (p<0.0001). When comparing the group R+S with R, a statistical difference was observed to be present (p<0.0001). CONCLUSIONS:: Pelvic radiation promotes systemic effects and some structural modifications in the ventral prostate of rats. These modifications can be prevented by oral supplementation with L-arginine.

Glomerular loss after arteriovenous and arterial clamping for renal warm ischemia in a swine model

ABSTRACT PURPOSE: To evaluate the glomerular loss after arteriovenous or arterial warm ischemia in a swine model. METHODS: Twenty four pigs were divided into Group Sham (submitted to all surgical steps except the renal ischemia), Group AV (submitted to 30 minutes of warm ischemia by arteriovenous clamping of left kidney vessels), and Group A (submitted to 30 minutes of ischemia by arterial clamping). Right kidneys were used as controls. Weigh, volume, cortical volume, glomerular volumetric density (Vv[Glom]), volume-weighted glomerular volume (VWGV), and the total number of glomeruli were measured for each organ. RESULTS: Group AV showed a 24.5% reduction in its left kidney Vv[Glom] and a 25.4% reduction in the VWGV, when compared to the right kidney. Reductions were also observed when compared to kidneys of sham group. There was a reduction of 19.2% in the total number of glomeruli in AV kidneys. No difference was observed in any parameters analyzed on the left kidneys from group A. CONCLUSIONS: Renal warm ischemia of 30 minutes by arterial clamping did not caused significant glomerular damage, but arteriovenous clamping caused significant glomerular loss in a swine model. Clamping only the renal artery should be considered to minimize renal injury after partial nephrectomies.

Nutritional supplementation with arginine protects radiation-induced effects. An experimental study

ABSTRACT PURPOSE: To investigate the protective effect of L-arginine on the prostate (nonneoplasic) of rats with radiation-induced injury. METHODS: Twenty-nine Wistar rats, male adult, allocated into three groups: Control group (C) was not exposed to irradiation (n=10); Radiated group (R) had undergone pelvic irradiation (n=10); Supplemented and radiated group (R+S) had undergone pelvic irradiation plus L-arginine supplementation (n=9). The animals were observed for signs of toxicity. After euthanization, the prostate was dissected under magnification and stained by hematoxylin and eosin to study acinar structures and stained with Picrosirius red for collagen analysis. RESULTS: After radiation exposure, all animals presented diarrhea, but supplementation with L-arginine reduced this effect. The weight gain in the R+S group was significantly higher than in the C and R groups. In the R+S group the collagen density and the prostate acinar area was similar to the R and C groups. Epithelial height was significantly reduced in group R compared with group C (p<0.0001). When comparing the group R+S with R, a statistical difference was observed to be present (p<0.0001). CONCLUSIONS: Pelvic radiation promotes systemic effects and some structural modifications in the ventral prostate of rats. These modifications can be prevented by oral supplementation with L-arginine.

Morphometric study of the corpus cavernosum after anabolic androgenic steroid administration in pubertal and adult rats

PURPOSE: To evaluate the penile morphological modifications of pubertal and adult rats chronically treated with supra-physiological doses of anabolic androgenic steroids. METHODS: Forty-eight male Wistar rats were distributed into four groups: two control groups, 105- and 65-day-old (C105 and C65, respectively) injected with peanut oil (vehicle); and two treated groups, 105- and 65-day-old (T105 and T65, respectively) injected with nandrolone decanoate at a dose of 10 mg Kg-1 of body weight. The rats were injected once a week for eight weeks. The rats were then killed and their penises were processed for histomorphometric analyses. The mean of each parameter was statistically compared. RESULTS: A corpus cavernosum reduction of 12.5% and 10.9% was observed in the T105 and T65 groups, respectively, when compared with their respective control groups. The cavernosum smooth muscle surface density diminished by 5.6% and 12.9% in the T65 and T105 groups, respectively, when compared with their controls. In contrast, the sinusoidal space increased by 17% in the T105 group and decreased by 9.6% in the T65 group. CONCLUSION: The use of supra-physiological doses of AAS promotes structural changes in the rat penis, by altering the proportions of corpus cavernosum tissues, in both pubertal and adult treated animals. .

Deleterious effects of prepubertal corticosterone treatment on rat prostate

PURPOSE:To investigate the structural and functional changes induced by corticosterone (CORT) in the ventral prostrate (VP) of rats in order to study chronic stress effects in the prepubertal phase.METHODS:Wistar rats received daily saline or CORT injections during the pubertal period from the 5th to 25th day of postnatal life. The animals were distributed into four groups: 1 - Control (n=5); 2 - Control 99mTc-P (n=5); 3 - Treated with CORT (n=14); 4 - Treated with CORT and 99mTc-P (n=10). All rats were sacrificed at two months of age. Technical tissue uptakes of 99mTc-P were used to evaluate the functional and stereological methods for morphological analysis.RESULTS:Acini distribution in the group treated with CORT differed significantly (p 0.0001) from the control. The control group's epithelial average height (10.01±0.24 microns) was statistically significant (p 0.0001) from rats treated with CORT (19.27±0.73microns). The collagen distribution was lower in the treated group (2.79%) when compared to control (3.97%). The radioactivity percentage in the groups marked with 99mTc-P (%Ati/g) did not demonstrate a statistically significant difference (p=0.285897).CONCLUSION:Chronic administration of corticosterone in prepubertal rats causes changes in their acinar structure and their ventral prostate stroma, indicating possible deleterious effects of this hormone.

Deleterious effects of prepubertal corticosterone treatment on rat prostate

PURPOSE: To investigate the structural and functional changes induced by corticosterone (CORT) in the ventral prostrate (VP) of rats in order to study chronic stress effects in the prepubertal phase. METHODS: Wistar rats received daily saline or CORT injections during the pubertal period from the 5th to 25th day of postnatal life. The animals were distributed into four groups: 1 - Control (n=5); 2 - Control 99mTc-P (n=5); 3 - Treated with CORT (n=14); 4 - Treated with CORT and 99mTc-P (n=10). All rats were sacrificed at two months of age. Technical tissue uptakes of 99mTc-P were used to evaluate the functional and stereological methods for morphological analysis. RESULTS: Acini distribution in the group treated with CORT differed significantly (p<0.0001) from the control. The control group's epithelial average height (10.01±0.24 microns) was statistically significant (p<0.0001) from rats treated with CORT (19.27±0.73microns). The collagen distribution was lower in the treated group (2.79%) when compared to control (3.97%). The radioactivity percentage in the groups marked with 99mTc-P (%Ati/g) did not demonstrate a statistically significant difference (p=0.285897). CONCLUSION: Chronic administration of corticosterone in prepubertal rats causes changes in their acinar structure and their ventral prostate stroma, indicating possible deleterious effects of this hormone. .

Structural study of endopelvic fascia in prostates of different weights. Anatomic study applied to radical prostatectomy.

PURPOSE: To evaluate the structure of the endopelvic fascia in prostates of different weights. METHODS: We studied 10 patients with BPH (prostates> 90 g); 10 patients with prostate adenocarcinoma (PAC) (prostates< 60 g) and five young male cadavers (control group). During the surgery a small sample of endopelvic fascia was obtained. We analyzed elastic fibers, collagen and smooth muscle. The stereological analysis was done with the Image Pro and Image J programs. Means were statistically compared using the one-way ANOVA with the Bonferroni test and a p<0.05 was considered statistically significant. RESULTS: The mean of the prostate weight was 122 g in BPH patients, 53.1g in PAC patients and 18.6g in control group. Quantitative analysis documented that there are no differences (p=0.19) in Vv of elastic fibers and in Vv of type III collagen (p=0.88) between the three groups. There was a significant difference (p=0<0.0001) in the quantification of SMC in patients with prostates > 90 g (mean=9.61%) when compared to patients with prostates < 60 g (mean=17.92%) and with the control group (mean=33.35%). CONCLUSION: There are differences in endopelvic fascia structure in prostates> 90 g, which can be an additional factor for pre-operatory evaluation of radical prostatectomy.

Structural study of endopelvic fascia in prostates of different weights. Anatomic study applied to radical prostatectomy

PURPOSE: To evaluate the structure of the endopelvic fascia in prostates of different weights. METHODS: We studied 10 patients with BPH (prostates>90g); 10 patients with prostate adenocarcinoma (PAC) (prostates<60g) and five young male cadavers (control group). During the surgery a small sample of endopelvic fascia was obtained. We analyzed elastic fibers, collagen and smooth muscle. The stereological analysis was done with the Image Pro and Image J programs. Means were statistically compared using the one-way ANOVA with the Bonferroni test and a p<0.05 was considered statistically significant. RESULTS: The mean of the prostate weight was 122 g in BPH patients, 53.1g in PAC patients and 18.6g in control group. Quantitative analysis documented that there are no differences (p=0.19) in Vv of elastic fibers and in Vv of type III collagen (p=0.88) between the three groups. There was a significant difference (p=0<0.0001) in the quantification of SMC in patients with prostates >90g (mean=9.61%) when compared to patients with prostates <60g (mean=17.92%) and with the control group (mean=33.35%). CONCLUSION: There are differences in endopelvic fascia structure in prostates>90g, which can be an additional factor for pre-operatory evaluation of radical prostatectomy. .

Structural changes of dilated pelvic ureters in adults.

PURPOSE: To perform a quantitative assessment of different types of pelvic ureter tissues with chronic dilation in adults, using stereological methods. METHODS: We analyzed fragments of dilated pelvic ureters obtained from 6 patients aged between 35 and 67 years (mean, 46 years) who underwent ureteral reimplantation surgery for different reasons. The obstruction duration ranged from 27 to 180 days (mean, 93 days). The control group included fragments of normal pelvic ureters obtained during nephrectomy in 7 kidney transplant donors (age: range, 25-51 years; mean, 36 years). The volumetric density of collagen in the ureter, elastic fibers, and smooth muscle fibers was assessed. RESULTS: The volumetric density (Vv) of collagen showed no significant difference between the two groups (control: 45.3 ± 6.1; dilated: 40.8 ± 6.9; P = 0.23). A statistically significant increase in Vv of elastic fibers was observed in the dilated ureters (control: 18.4 ± 1.2; dilated: 24.6 ± 5.4; P = 0.03). A statistically significant increase in the Vv of smooth muscle fibers was observed in the dilated ureter (control: 42.0 ± 6.0; dilated: 56.2 ± 6.1; P = 0.001). CONCLUSION: The chronically dilated pelvic ureters had significantly more elastin and smooth muscle contents than the controls.

Structural changes of dilated pelvic ureters in adults

PURPOSE: To perform a quantitative assessment of different types of pelvic ureter tissues with chronic dilation in adults, using stereological methods. METHODS: We analyzed fragments of dilated pelvic ureters obtained from 6 patients aged between 35 and 67 years (mean, 46 years) who underwent ureteral reimplantation surgery for different reasons. The obstruction duration ranged from 27 to 180 days (mean, 93 days). The control group included fragments of normal pelvic ureters obtained during nephrectomy in 7 kidney transplant donors (age: range, 25-51 years; mean, 36 years). The volumetric density of collagen in the ureter, elastic fibers, and smooth muscle fibers was assessed. RESULTS: The volumetric density (Vv) of collagen showed no significant difference between the two groups (control: 45.3 ± 6.1; dilated: 40.8 ± 6.9; P = 0.23). A statistically significant increase in Vv of elastic fibers was observed in the dilated ureters (control: 18.4 ± 1.2; dilated: 24.6 ± 5.4; P = 0.03). A statistically significant increase in the Vv of smooth muscle fibers was observed in the dilated ureter (control: 42.0 ± 6.0; dilated: 56.2 ± 6.1; P = 0.001). CONCLUSION: The chronically dilated pelvic ureters had significantly more elastin and smooth muscle contents than the controls. .