Corpus cavernous smooth muscle cells are the main functional component of the corpus cavernosum penis, whose phenotypic modulation is the key initial step in the proliferation and migration of smooth muscle cells. Therefore, an insight into the mechanism of the phenotypic modulation of smooth muscle cells and its influencing factors is important for the prevention and management of penis erectile dysfunction. Smooth muscle cells are generally divided into contracting (differentiated) and composing (undifferentiated, proliferated or dedifferentiated) types. It is found that TGF-beta, transcription factor E2F1, BTEB2 and insulin may affect the phenotypic modulation of smooth muscle cells. This paper presents an overview of the progress in the researches on the phenotypic modulation of corpus cavernous smooth muscle cells and its influencing factors.
Cells, Cultured ; Humans ; Male ; Muscle, Smooth ; cytology ; Myocytes, Smooth Muscle ; classification ; cytology ; ultrastructure ; Penis ; Phenotype

The contractility of corporal smooth muscle plays a critical role in human penile erectile process. Understanding the initiation, maintenance and modulation of corporal smooth muscle tone is a prequisite to improve understanding, diagnosis and treatment of erectile dysfunction. Despite this fact, indentification of both the precise mechanistic basis by which various agents exert their effects on individual corporal smooth muscle cells, moreover, the process by which these signals are spread among the diverse array of parenchymal cells in the paired corporal, remain somewhat of a physiological enigma. Therefore, this article aims at: 1. to review current knowledge of the regulation of corporal smooth muscle tone at the cellular and molecular level; 2. to review various methods used in the study of gap junction channel.
Animals ; Connexins ; physiology ; Gap Junctions ; physiology ; Humans ; Intercellular Junctions ; physiology ; Male ; Muscle, Smooth ; physiology ; Penis ; cytology

OBJECTIVETo explore the pathogenesis of male sexual dysfunction by studying cell apoptosis and carbonate monoxide (CO) contents in the penile tissue of rats at different ages.

METHODSWe equally divided 24 male Wistar rats into an adult group (8 months old), an elderly group (16 months old) and an aged group (24 months old), and detected cell apoptosis by HE staining and TUNEL and CO levels in the penile tissues of different groups by modified dual-wavelength spectrophotometry.

RESULTSCell apoptosis increased with aging: 4.38 +/- 1.06 in the adult, 9.38 +/- 1.69 in the elderly and 18.50 +/- 1.60 in the aged group, while the CO content decreased with aging: 12.19 +/- 0.87 in the adult, 7.93 +/- 0.63 in the elderly and 5.68 +/- 0.62 in the aged group, both with statistically significant differences among the 3 groups (P < 0.05). The change of cell apoptosis showed a good negative correlation with that of the CO content (r = -0.889, P < 0.01).

CONCLUSIONCell apoptosis and CO content change in the penile tissue of aging rats, and CO may participate in the development of ED by regulating cell apoptosis.

Aging ; Animals ; Apoptosis ; Carbon Monoxide ; metabolism ; Male ; Penis ; cytology ; metabolism ; Rats ; Rats, Wistar

OBJECTIVETo investigate an effective method to produce large numbers of pure corporal smooth muscle cells in vitro according to the requirement of study.

METHODSIn this study, we used the primary tissue culture technique to isolate and culture the corpus cavernosum smooth muscle cells (CCSM) from human males with normal erectile function and New Zealand white rabbits. The cells were identified in regard to morphological and growing characteristics via immunohistochemical methods (including alpha-smooth muscle actin, desmin, myocin and factor VIII related antigen), special dye techniques (including Masson and Van Gieson) and transmission electron microscope.

RESULTSCCSM were isolated and cultured successfully with high purity. Morphologically, the cells were spindle shaped and grow on top of each other, resembling a "hill and valley" in appearance. When characterized in immunohistochemistry, the cells were stained with alpha-smooth muscle actin, desmin and myocin, but not with anti-factor VIII, an endothelial marker.

CONCLUSIONThe CCSM, which can be isolated and cultured successfully, may be used for further studying their biological function. The CCSM cultured in vitro was proved to be useful to evaluate and investigate the effect of some new medicine for penile erection. There is also a clinical and theoretical significance in further studying the experimental mechanisms of erectile dysfunction.

Animals ; Cell Division ; Cells, Cultured ; Erectile Dysfunction ; etiology ; Humans ; Immunohistochemistry ; Male ; Myocytes, Smooth Muscle ; chemistry ; cytology ; ultrastructure ; Penis ; cytology ; Rabbits

OBJECTIVETo evaluate the effect of aging on the endothelial function of the penile corpus cavernosum in rats.

METHODSThe intracavernosal pressure (ICP) was compared in response to acetylcholine (Ach, endothelium-dependent vasodilator), sodium nitroprusside (SNP, an NO donor) and A23187 (a calcium ionophore)in the young (5 months old) and aged (20 months old) rats. In addition, the activity of nitric oxide synthase (NOS)in penile cavernosal tissues was examined.

RESULTSAch-mediated ICP was significantly attenuated from the maximum of (54.8 +/- 4.2) in the young rats to (40.3 +/- 2.8) mm Hg in the aged ones (Ach = 0.1 mmol/L), P < 0.01. The ICP to SNP (0.1 mmol/L) was (58.9 +/- 4.7) mm Hg in the young rats and (51.7 +/- 5.3) mm Hg in the aged. No statistically significant difference was noted between the two groups, P > 0.05. The Ach-mediated ICP in the young rats was not significantly augmented from the maximum of (54.8 +/- 4.2) to (55.8 +/- 4.7) mm Hg in the presence of the calcium ionophore A23187 (10 micromol/L), P > 0.05. However, A23187 significantly augmented Ach-mediated ICP in the aged from the maximum of (40.3 +/- 2.8) to (56.2 +/- 4.1) mm Hg, P < 0.01. Finally the activity of nitric oxide synthase was not significantly attenuated in either the aged or the young, P > 0.05.

CONCLUSIONThe endothelial function of the penile cavernosum declines with the advance of age. And endothelial dysfunction may play some role in the mechanisms of age-related erectile dysfunction.

Aging ; physiology ; Animals ; Endothelial Cells ; physiology ; Male ; Nitric Oxide Synthase ; metabolism ; Penis ; cytology ; metabolism ; physiology ; Rats ; Rats, Wistar

OBJECTIVETo explore the relationship between hypoxia and the apoptosis of corpus cavernosum smooth muscle cells (CCSMC) in SD rats.

METHODSCCSMCs were cultured in vitro and identified by immunohistochemistry, and then underwent hypoxia interference at the concentration of 1% O2 for 12, 24, 48 and 72 hours, with normal oxygen concentration as the control. Flow cytometry was used to determine the cycles and apoptosis of the cells.

RESULTSThe cultured CCSMCs grew well, positive for anti-smooth muscle alpha-actin monoclonal antibody immunohistochemical staining. Flow cytometry showed that the number of CCSMCs in G0/G1 was gradually increased within 48 hours and then decreased, just opposite to the proportion of the S phase cells. But no regular change was found in the proportion of the cells in the G2/M phase.

CONCLUSIONHypoxia promotes the apoptosis of CCSMCs in a time-dependent manner, to the maximum at 48 hours, and then cell lysis may occur, but with no further apoptosis.

Animals ; Apoptosis ; Cell Hypoxia ; Cells, Cultured ; Male ; Muscle, Smooth, Vascular ; cytology ; Penis ; pathology ; Rats ; Rats, Sprague-Dawley

Tissue engineering techniques, with their potential applied value for penile reconstruction, are of special interest for andrologists. The purpose of this review is to appraise the recent development and publications in this field. In the past few years, great efforts have been made to develop corpus cavernosum tissues by combining smooth muscle and endothelial cells seeded on biodegradable polyglycolic acid polymer (PGA) or acellular corporal collagen matrices scaffolds. Animal experiment demonstrated that the engineered corpus cavernosum achieved adequate structural and functional parameters. Engineered cartilage rods as an alternative for the current clinical standard of semirigid or inflatable penile implants could be created by seeding chondrocyte cylindrical PGA. A series of studies showed that, compared to commercially available silicone implants, the engineered rods were flexible, elastic and stable. Besides, a variety of decellularized biological materials have been used as grafts not only for substitution of tunica albuginea but also for penile enhancement, with promising results. For treating erectile dysfunction, a new approach to recovering erectile function by cell-based therapy could be the injection of functional cells into corpus cavernosum, which seemed to be promising when combined with cell manipulation by gene therapy prior to cell transfer.
Cell Transplantation ; Endothelial Cells ; transplantation ; Erectile Dysfunction ; surgery ; Humans ; Male ; Muscle, Smooth ; cytology ; Penile Prosthesis ; Penis ; physiology ; surgery ; Tissue Engineering

The regulation of vascular and trabecular smooth muscle relaxation or contraction in the penis, that is, the physiology of corporal smooth muscle tone, determines penile erection or flaccidity. There is considerable evidence that the potassium channel and calcium channel, like many other vascular tissues, are the major modulators of smooth muscle tone in the corpora. Moreover, data on cultured corporal smooth muscle cells and isolated corporal tissue strips have demonstrated that the neurotransmitters participating in erection modulate corporal smooth muscle tone largely through their effects on ionic channels and transmembrane ionic flux.
Cell Line ; Humans ; Ion Channels ; physiology ; Male ; Muscle Contraction ; physiology ; Muscle, Smooth ; cytology ; physiology ; Penis ; cytology ; physiology ; Potassium Channels ; physiology ; Sodium Channels ; physiology

OBJECTIVETo explore the effects of salidroside on the phenotypic modulation of corpus cavernosum smooth muscle cells (CCSMC) in hypoxic SD rats.

METHODSCCSMCs were cultured in vitro and identified by immunohistochemistry. The cells were divided into six groups: normal control (21% O2), hypoxia (1% O2), hypoxia + salidroside 1 mg/L, hypoxia + salidroside 3 mg/L, hypoxia + salidroside 5 mg/L and hypoxia + PGE1 0.4 microg/L, and then cultured for 48 hours. The relative expressions of alpha-actin and osteopontin (OPN) in each group were determined by RT-PCR.

RESULTSThe in vitro cultured CCSMCs grew well, with anti-alpha-smooth muscle actin monoclonal antibodies immunohistochemically positive. The relative expression of alpha-actin was markedly decreased while that of OPN remarkably increased in the hypoxia group as compared with the normal control group (P < 0.01). The hypoxia + salidroside 5 mg/L group showed a significantly higher expression of alpha-actin and lower expression of OPN than the hypoxia group (P < 0.01), but exhibited no significant differences from the hypoxia + PGE group (P > 0.05).

CONCLUSIONHypoxia can reduce the relative expression level of alpha-actin and increase that of OPN in the CCSMCs of SD rats, namely, induce their phenotypic modulation from the contraction to the non-contraction type. Salidroside can restrain hypoxia-induced phenotypic modulation of CCSMCs, and its inhibitory effect at 5 mg/L is similar to that of PGE1.

Actins ; metabolism ; Animals ; Cell Hypoxia ; Cells, Cultured ; Glucosides ; pharmacology ; Male ; Myocytes, Smooth Muscle ; cytology ; metabolism ; Osteopontin ; metabolism ; Penis ; cytology ; Phenols ; pharmacology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo culture rat corpus cavernosum smooth muscle cells in vitro using a modified tissue culture method.

METHODSFifteen male rats were randomized into 3 equal groups, namely enzyme digestion group, tissue culture group, and modified tissue culture group. The penis of the rats was separated carefully and cut into small pieces, and seeded onto culture flasks and cultured in complete medium consisting of DMEM containing 20% fetal calf serum at 37 degrees C; in a humidified atmosphere with 5% carbon dioxide. The cells growth was observed under phase contrast microscope and the smooth muscle cell specific proteins alpha-SM-actin and desmin were identified immunohistochemically.

RESULTSThe alpha-SM-actin-positive cell rate was 96.3% in rat corpus cavernosum smooth muscle and 23.8% in the fibroblasts, and the corpus cavernosum smooth muscle contained 74.4% desmin-positive cells while the fibroblasts showed no desmin positivity. Significant difference was found in the positive cell rate for desmin among the 3 groups, with the highest positive cell rate occurred in modified tissue culture group.

CONCLUSIONDesmin may serve as a marker for identifying corpus cavernosum smooth muscle cells. The modified tissue culture method can result in highly purified corpus cavernosum smooth muscle cells with intact structure and functions.

Actins ; analysis ; Animals ; Biomarkers ; analysis ; Cell Proliferation ; Desmin ; analysis ; Male ; Muscle, Smooth ; cytology ; Penis ; cytology ; Rats ; Rats, Sprague-Dawley ; Tissue Culture Techniques