Culture of human corpus cavernosum endothelium

Structural and functional abnormalities of penile cavernous endothelial cells result in erectile dysfunction at experimental autoimmune prostatitis rat

Background

There is growing recognition of the association of CP/CPPS accompany with ED. However, the specific mechanism of action remains unclear. The aim of this study was to investigate structural and functional abnormalities of cavernous endothelial cells in EAP rat, which may result in the ED.

Methods

we use rat prostate protein extract supplemented with immunoadjuvant to induce EAP rat, ICP and MAP were measured and inflammatory factor infiltration, Akt, eNOS, AR, nNOS and iNOS in the corpus cavernosum were tested. Subsequently, the normal rat and EAP rat cavernosum endothelial cells were purified by MACS, and the metabolism, oxidative stress, MMP, Akt, eNOS, AR and iNOS were evaluated.

Results

The EAP rat model was successfully constructed. The ratio of max ICP/MAP in EAP rat was significantly lower and TNF-α infiltration in corpus cavernosum was significantly higher than normal rats. Besides, Akt, eNOS and AR were decreased, iNOS was significantly increased. The growth and metabolism of endothelial cells in the EAP rats corpus cavernosum decreased and inflammatory factor mRNA was increased and intracellular oxidative stress was also increased significantly. The MMP of EAP rats cavernosum endothelial cells decreased and the expression of Akt, eNOS and AR were also significantly decreased, iNOS was significantly increased.

Conclusion

The prostate suffer local inflammatory infiltrate and promotes cytokines infiltrated into corpus cavernosum caused the oxidative stress increases and the metabolism or MMP decreases. In addition, AR, Akt and eNOS expression and phosphorylation are also reduced, thereby inhibiting the diastolic function of the corpus cavernosum, resulting in decreased erectile function.

Separation, culture and identification of SD rat corpus cavernosal endothelial cells

The aim of the study is to investigate the methods of separation, culture and identification of Sprague Dawley (SD) rat corpus cavernosal vascular endothelial cells (CCECs). Cavernosal tissues were isolated from male SD rats. Enzymatic digestion was applied to separate CCECs. Purified cells were obtained using immunomagnetic beads and flow cytometric cell sorting and subcultured in EMG-2 medium. The growth curve of CCECs was measured by the tetrazolium salt 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. The cells were identified by von Willebrand factor (vWF) using immunofluorescence, and the positive percentage of vWF expression was detected by flow cytometry. The monomorphic cobblestone-like cells were observed by microscopy. High purification was obtained using immunomagnetic beads. After 2 days of incubation, cells entered the logarithmic growth phase and reached a plateau on the fifth day. The vWF expression in cytoplasm was positive. The purity of cells was 95.8%, which was tested by flow cytometry. SD rat CCECs can be separated and cultured successfully by the method of enzymatic digestion, immunomagnetic beads and flow cytometric cell sorting.

Isolation of Primary Endothelial and Stromal Cell Cultures of the Corpus Cavernosum Penis for Basic Research and Tissue Engineering

OBJECTIVES

Primary cell cultures derived from the corpus cavernosum are frequently used as in vitro models to define cellular mechanisms involved in erectile function. However, previous studies often lack detailed isolation protocols or a precise characterisation of the culture composition excluding especially contaminating fibroblasts. This study aimed at critically analysing and reproducing reported isolation methods, as well as establishing new procedures to receive highly pure and morphologically differentiated endothelial, smooth muscle and fibroblastic cells derived from the human penis.

METHODS

We evaluated numerous isolation and enrichment techniques using cavernosal tissue from 57 patients. Assessment factors displayed the purity, cell yield, practicability and reproducibility. The purity in cultured cells was analysed using immunocytochemistry and Western blots.

RESULTS

An enzymatic protocol was established for the isolation and cultivation of cavernosal endothelial cells with an impressive purity of 98.0+/-0.8%. In contrast, already published nearly pure smooth muscle cell cultures were not reproducible in our laboratory. Meaningful evidence for an overwhelming presence of fibroblasts in these widely accepted pure smooth muscle cell cultures is presented.

CONCLUSION

Endothelial cell cultures derived from human corpora cavernosa are reproducible and reliable to serve for cell culture-based investigations of the endothelial dysfunction. The discrepancy in the purity of smooth muscle cell cultures might reflect laboratory and tissue source factors, lacking an exclusion of fibroblasts in other studies or changes in stromal phenotype under culture conditions. Further research is necessary to clarify a possible plasticity between smooth muscle cells and (myo)fibroblasts and assess functional properties.

Gap junction messenger RNA expression by vascular wall cells

Gap junctions between vessel wall cells provide a pathway for the intercellular exchange of ions and small molecules. Pure cultures of microvascular and macrovascular endothelial and smooth muscle cells, vascular pericytes, and several nonvascular cell lines were tested for junctional communication by fluorescent dye transfer. All of the vascular wall cells were capable of dye transfer. Since gap junctions are formed by a family of related proteins (connexins) whose unique domains may confer physiological regulatory properties, we tested total RNA from these cultures by Northern blot analysis for expression of the currently available, characterized, and cloned mammalian gap junction proteins: connexin26, connexin32, and connexin43. All of the vascular wall cells expressed connexin43 messenger RNA. Connexin43 was expressed in vascular cells from bovine, porcine, rat, and human sources. Several nonvascular cell lines of mesenchymal origin also expressed connexin43 messenger RNA. When high stringency Northern blots were used, messenger RNAs for connexin32 or connexin26 were not detected in any of the vascular wall cells but were expressed in several cell lines of epithelial origin. Freshly isolated and purified aortic endothelial and smooth muscle RNA preparations similarly contained only connexin43 messenger RNA, excluding the possibility of culture-induced alterations in gene expression. The expression of connexin43 by all vascular wall cells may provide a mechanism for the functional integration of the vessel wall by gap junctions.