Muscle Cells Of Corpus Cavernosum Research Articles

The Effects of Calorie Restriction and Exercise on Age-Related Alterations in Corpus Cavernosum.

BackgroundAging is an important risk factor for erectile dysfunction (ED). Both calorie restriction (CR) and physical exercise (PE) have been established as a non-medical method for the improvement of detrimental changes in aging. It is well documented that both CR and PE influence on sympathetic and parasympathetic systems; however, there are few studies on non-adrenergic non-cholinergic pathways. This study aims to investigate the NO-mediated mechanisms of CR and PE on corpus cavernosum in aged rats.Materials and Methods3 and 15 month-old rats were divided into five experimental groups: young rats fed ad libitum (Y-C), aged rats fed ad libitum (O-S), aged rats with CR (O-CR), aged rats with PE (O-PE), and aged rats with CR and PE (O-CR-PE). CR was applied to animals as a 40% reduction of daily food intake for 6 weeks. PE was moderate swimming at 30 min at 3 days/week. The effects of CR and PE were evaluated by histologic, biologic, and in-vitro tissue bath studies.ResultsThe outcomes in CR and PE groups (characterized by decreased nitrosative damage together with increased antioxidant capacity) were improved in comparison to the O-S. Apoptotic biomarkers were also lower and both endothelial and smooth muscle cell’ functions were preserved too. There was no statistical difference between apoptosis, antioxidant capacity, and nitrosative damage parameters. Contractile responses to phenylephrine and relaxation responses to carbachol were: O-CR > O-PE > O-CR-PE. In these groups, NOS protein levels determined by western-blot were: eNOS: O-CR = O-CR + PE > O-PE; iNOS: O-CR = O-PE > O-CR-PE; nNOS: O-PE > O-CR-PE > O-CR.ConclusionIn our study, both CR and PE prevented age-related changes in the corpus cavernosum of rats. Reducing nitrosative damage in the neurovascular structure was the main mechanism. CR and exercise restored the endothelial and smooth muscle cells in corpus cavernosum by decreasing apoptosis. The mechanism of enhancing functional response in corpus cavernosum with CR was the improvement of endothelial function via eNOS activation however it involves increases in the NO-cGMP signaling pathway by an endothelium-independent mechanism with PE. This might be a direct stimulation of smooth muscle cells by NO, which released from the cavernous nerve endings via nNOS activation.

Long-term Oral Administration of 5α-reductase Inhibitor Attenuates Erectile Function by Inhibiting Autophagy and Promoting Apoptosis of Smooth Muscle Cells in Corpus Cavernosum of Aged Rats

Long-term Oral Administration of 5α-reductase Inhibitor Attenuates Erectile Function by Inhibiting Autophagy and Promoting Apoptosis of Smooth Muscle Cells in Corpus Cavernosum of Aged Rats

Long-term Oral Administration of 5α-reductase Inhibitor Attenuates Erectile Function by Inhibiting Autophagy and Promoting Apoptosis of Smooth Muscle Cells in Corpus Cavernosum of Aged Rats

To investigate the effects and mechanisms of long-term treatment of 5α-reductase inhibitors (5ARIs) on erectile organ structure and function in aged rats. Thirty 16-month-old male rats were assigned to 2 groups: untreated or treated with 5ARIs. After 16 weeks, the erectile function was measured after electrical stimulation of the cavernous nerve. The weights and histopathologic features of the corpus cavernosum were examined. The levels of autophagy, apoptosis, and protein expression were also recorded. In the 5ARI-treatment group, the plasma and intraprostatic dihydrotestosterone concentration was lowered by 52.1% and 57.3%, respectively, and the weight of the corpus cavernosum and prostate had decreased by 22.4% and 35.6%, respectively. The invivo erectile response to electrical stimulation of the cavernous nerve had decreased significantly in the 5ARI-treatment group (P<.001). Masson's staining, immunohistochemistry, and Western blot all demonstrated decreased smooth muscle and increased collagen deposition and decreased endothelial nitric oxide synthase and LC3-II protein expression in the corpus cavernosum of the 5ARI-treatment group. Using transmission electron microscopy and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling, decreased autophagy, aggravated ultrastructural injury of mitochondria, and increased apoptosis were observed in the cavernous smooth muscle cells from the rats in the 5ARI-treatment group. Long-term 5ARI treatment did attenuate the erectile function of aged rats. The mechanisms might have been the decreased rate of autophagy and an increased rate of apoptosis in the cavernous smooth muscle cells, suggesting a new role for androgen in maintaining the structural and functional integrity of the erectile organ. Additional studies are necessary to demonstrate the mechanisms of dihydrotestosterone in regulating the autophagy and apoptosis of the cavernous smooth muscle cells.

SEXUAL ABSTINENCE AND IMMOBILISATION STRESS DECREASED NITRATE + NITRITE CONCENTRATION AND INCREASED NECROTIC OF PENILE CORPUS CAVERNOSUM SMOOTH MUSCLE AND ENDOTHELIAL CELLS OF ADULT MALE MICE

Sexual intercourse in adult people is not only related to reproduction,recreation and better relation but also for maintaining good health. Regular andfrequent sexual intercourse has protective role for cardiovascular disease, malignancyand often related with longevity. On the contrary less frequent sexual intercourse isoften correlated to early death and reproductive organ disorders. One main factorwhich involve in any process related to sexual intercourse is nitric oxide. Thisresearch aims to know the declination of total nitrate and nitrite concentration as themain oxidation product of nitric oxide and necrosis of the endothelial and smoothmuscles of corpus cavernosum after three month sexual intercourse abstinence andstress immobilization.By randomized pretest-posttest control group design, the research wasconducted in adult male mice (Mus musculus) which were divided into four groups.each consisted of seven mice. One group as a control and the other three wereexposed to sexual abstinence, immobilization stress and the combination of sexualabstinence and immobilization stress in three months period. The investigation wascarried out to the penile total nitrate and nitrite concentration and the histologicalchanges of the middle part of the penile shaft. To know the degree of lesion then thecalculation of the histologic features was done in five view fields of every preparat.The result was compared to control group.In this research, the mean of total nitrate and nitrite decline and the lowest wasfound in the combine intervention groups with significance level p &lt; 0,005. Thecorpus cavernosum in the intervention groups showed multifocal necrosis onendothelial and smooth muscle cells of corpus cavernosum with picnotic nuclei,irregular form and dark colour. Some muscle cells are lysis. These features werefound in three among seven samples in sexual abstinence group, two among sevensamples in immobilization stress group and in all samples of combined interventiongroup.Conclusions can be drawn from this research are that the sexual abstinence,immobilization stress and the combine interventions decline the nitrate and nitriteconcentrations and induce endothelial and smooth muscle cells necrosis of the copuscavernosum.

EFFECTS OF SENSE TANKYRASE TRANSFECTION ON SMOOTH MUSCLE CELLS OF CORPUS CAVERNOSUM IN RAT

This study was conducted to construct the eukaryotic expression vectors for sense tankyrase and to investigate the effects of tankyrase transfection on smooth muscle cells of corpus cavernosum in the rat. After the eukaryotic expression vectors for sense tankyrase were constructed and identified smooth muscle cells of rat corpus cavernosum were transfected with the recombinant plasmids of sense tankyrase (pcDNA-TNKS). Levels of DNA and RNA were then evaluated. Measurement of telomerase activity was conducted by TRAP-ELISA assay, the length of telomere by Southern blot and the growth curve by MTT assay. We have found that the eukaryotic expression vectors for sense tankyrase were constructed and the recombinant plasmids of sense tankyrase were transfected into smooth muscle cells of rat corpus cavernosum successfully; no significant differences in telomerase activity were observed between TNKS-transfected cells (SMC-TANKS), zero-load- transfected cells (SMC-Zeo), and non-transfected cells (SMC) (P > 0.05). The length of telomere in SMC-TANKS was longer than that in SMC-Zeo or SMC (P < 0.01), and the OD value of TNKS-transfected cell was significantly higher than that of the non-transfected cells (P < 0.01). These results suggested that the eukaryotic expression vectors for sense tankyrase were constructed successfully, which provides the basis for gene therapy. Transfection of recombinant plasmids of sense tankyrase helps change the telomerase length of smooth muscle cells of corpus cavernosum and extend the cell life span.

QUANTITATIVE ANALYSIS OF SMOOTH MUSCLE FIBERS IN CORPUS CAVERNOSUM OF HUMAN FETUSES

Purpose Quantify objectively the normative distribution and the percentage of smooth muscle fibers in the corpus cavernosum of human fetuses with 24 weeks post-conception (WPC) of gestational age. Material and Methods We studied 7 penises taken from 7 fresh human fetuses. We analyzed 5 randomized sections from each penis and in every section we analyzed 3 fields, totaling 15 fields per penis and 105 fields for the final results. Immunohistochemical staining for the smooth muscle fibers was used to accentuate the differences between the intracavernous structures (smooth muscle fibers and collagen fibers). The fields studied were digitized with a final magnification of 450X and a computerized analysis of the smooth muscle fibers was performed with image analyzer software. The percentage of smooth muscle fibers per standard square area was estimated and the mean value was used for each penis. Results The distribution of smooth muscle fibers in the corpus cavernosum of human fetuses with 24 WPC of gestational age ranged from 17.52% to 27.76% of the total area. The mean value was 22.72% and the standard deviation was 3.56. Conclusions Our results show that the percentage of smooth muscle cells in corpus cavernosum of human fetuses with 24 WPC of gestational age is significantly smaller when compared with the data available for adult cadavers.