| ObjectiveThis work aimed to analyze quantitative changes of peritubular cells in testes of aged mice, rats and humans, and to provide the data basis that could aid to evaluate the effect of aging on the testicular cells and explore the influence on aged physiology.Material and Methods1.(1) Testicular tissues were obtained by orchiectomy from 42 aged men (mean age, 74.9±4.2 years) with advanced prostate cancers. The patients eligible for inclusion were:a) not accept chemotherapy; b) did not affect the endocrine function for pharmacological treatment. According to inclusion criteria,16 young men (mean age,32.6±3.7 years) with biopsy for assisted reproductive detection served as controls. By pathologic observation, patients of Sertoli cell only syndrome (SCOS), testicular feminization, cryptorchidism were excluded. This study was approved by the ethics committee of the First Affiliated Hospital of Jinan University. All patients and subjects were informed.(2) Thirty male adult mice were divided into 2 groups (n=15) randomly including young groups (6 months) and aged groups (18 months).(3) Sixty-three male adult Sprague-Dawley rats were divided into 21 groups (n=3) randomly including control groups (group A1, A2, A3) and treated groups (B1～G1, B2～G2, B3～G3). The treated groups were treated for acute effects, chronic effects 2 and 4 months which were respectively given solutions containing Cd2+ 2.9, Cd2+ 5.8, Ni2+ 5, Ni2+ 50, Cd2+ 2.9+ Ni2+ 5, Cd2+ 5.8+ Ni2+ 50 mg/kg-day while control groups were given equal volume of normal saline instead.2. Tissue samples were fixed and processed conventionally for paraffin embedment, stained with haematoxylin and eosin. Ten round or nearly round tubule profiles were chosen randomly and nuclei of PCs, SCs and pachytene germ cells (pGCs) were calculated at Nikon E200 light microscope (magnification 100×/1.25 oil). Eight items were made to describe pathologic phenomenon, each item scores 1-5, the values are from 1 to 40 every sub-scales. Fifteen to twenty fields of view were selected randomly from each section, which uniformly acquired and snapped at 100x or 400×magnification by CCD photo software. The customized image processing program was used to calculate the diameter, area and perimeter of the seminiferous tubule by IPP. Mask grids were superimposed on images to measure parameters of testicular cells based on the stereological theory.Results1. No significant differences were found in cell ratio, peritubular cell number per tubule, diameter of seminiferous tubules between young and old men (P>0.05). Aged men had higher pathologic assignment score than that of young men, which demonstrated more severe pathologic changes (P<0.05). Peritubular cell volume density (Vv) and pachytene germ cell Vv increased significantly in old men for comparison to young men (P<0.05). Sertoli cell number per tubule in two-dimensional was significantly less in aged men than that of young men, P<0.01. Peritubular cell numerical density on area (NA), numerical density (Nv) decreased significantly in aged men compared with young men, P<0.05.2. Compared with young mice, pathologic assignment scores of aged mice were significantly higher than that (P<0.05); Germ cells numerical density of aged mice were reduced significantly compared with young groups (P<0.05). There was no significant changes of peritubular cells in aged mice, P>0.05.3. Compared with rat control groups, pathologic assignment scores of group G1,F1,G2 were risen (P<0.05); cell ratios between pachytene germ cells and Sertoli cells of group B2～G2 were decreased significantly (P<0.05). Sertoli cells Vv and NA of group B1, D1, G2 Nv of group C1, D1 were all higher than control groups (P<0.05), except group G3 was lower (P<0.01). Germ cells Vv of group C1～G1, G2, G3 were reduced significantly compared with control groups (P<0.01).Conclusions1. It is concluded that the stereological data of peritubular cells were decreased significantly from three-dimensional level in testes of aged men when compared with young men, which is indicative of aged-related fibrotic thickening of the tunica albuginea induced decreasing in the number of peritubular cell.2. Aged mice was displayed plummet changes on the testis injuries of age, but there is no significant changes of peritubular cells. The stereological numbers demonstrate damaged Sertoli cells and decreased germ cells, which is indicative of spermatogenic disturbance.3. Germinal epithelium injuries, pathologic changes of seminiferous tubule, spermatogenic disturbance in rat testes caused by the treatment with combined CdCl2 and NiSO4 were more obviously than respevtively, and these changes were more severe with increasing dose and time. It was demonstrated by stereological numbers that CdCl2 and NiSO4 caused severe changes in Sertoli cells and germ cells. No significant changes of peritubular cells were found which is indicative of that peritubular cells were not target cells of CdCl2 and NiSO4. |
