COMP-Angiopoietin-1 Promotes Cavernous Angiogenesis in a Type 2 Diabetic Rat Model

Cartilage oligomeric matrix protein-angiopoietin-1 (COMP-Ang1) is an angiogenic factor for vascular angiogenesis. The aim was to investigate the effect of an intracavernosal injection of COMP-Ang1 on cavernosal angiogenesis in a diabetic rat model. Male Otsuka Long-Evans Tokushima Fatty (OLETF) rats made up the experimental group (1 yr old) and Long-Evans Tokushima Otsuka (LETO) rats made up the control group. The experimental group was divided into vehicle only, 10 microg COMP-Ang1, and 20 microg COMP-Ang1. COMP-Ang1 was injected into the corpus cavernosum of the penis. After 4 weeks, the penile tissues of the rats were obtained for immunohistochemistry and Western blot analysis. The immunoreactivity of PECAM-1 and VEGF was increased in the COMP-Ang1 group compared with the vehicle only group. Moreover, the expression of PECAM-1 and VEGF was notably augmented in the 20 microg Comp Ang-1 group. In the immunoblotting study, the expression of PECAM-1 and VEGF protein was significantly less in the OLEFT rats than in the control LETO rats. However, this expression was restored to control level after intracavernosal injection of COMP-Ang1. These results show that an intracavernosal injection of COMP-Ang1 enhances cavernous angiogenesis by structurally reinforcing the cavernosal endothelium.

Expression and Translocation of Aquaporin (AQP)-1 after Pelvic Nerve Stimulation in Rat Vagina / 대한남성과학회지

PURPOSE: Aquaporins (AQPs) are membrane proteins that facilitate water movement across biological membranes. The purposes of this study were to investigate the localization and functional roles of AQP-1 water channels in rat vagina. MATERIALS AND METHODS: Female Sprague-Dawley rats (230~240 g, n=40) were anesthetized. To investigate the expression and localization of AQPs in the vagina, the vaginal branch of the pelvic nerve was stimulated for 60 seconds (10 V, 16 Hz, 0.8 msec), and then the animals were sacrificed immediately or 5 minutes later. The expression and cellular localization of AQP-1 in the vaginal tissue was measured by Western blot and immunohistochemistry. The cytosolic (or intracellular membrane) and plasma membrane fractions of AQP-1 in vaginal tissue were studied by immunoblot analysis. RESULTS: Immunolabeling showed that AQP-1 was mainly expressed in the capillaries and venules of the vagina. The translocation of AQP-1 isoforms from the cytosolic compartment to the plasma membrane compartment was observed right after nerve stimulation and had declined at 5 minutes after nerve stimulation. However, when the nerve stimulation was repeated 3 times, the translocation of AQP-1 from the intracellular membrane compartment to the plasma membrane compartment was still observed at 5 minutes. CONCLUSIONS: This study suggests that sexual arousal induced by pelvic nerve stimulation modulates AQP-1 activity in the rat vagina. This result implies that AQP-1 may play an important role in vaginal lubrication.

Effects of Testosterone on the Expression of Transforming Growth Factor (TGF)-beta1 in Rat Penile Corpus Cavernosum / 대한남성과학회지

PURPOSE: The aim of this study was to elucidate the effect of testosterone on the expression of transforming growth factor (TGF)-beta1 in rat penile corpus cavernosum. MATERIALS AND METHODS: Male Sprague Dawley rats (n=60) were divided into 3 groups: control, castration, and testosterone replacement after castration. Testosterone was administered for 7 days at week 1 and week 2 after castration. The intracavernosal pressure/systemic blood pressure was recorded after pelvic nerve stimulation. Expression of TGF-beta1 was determined by immunoblotting and immunohistochemistry. RESULTS: At week 1 and 2 after castration, the intracavernosal pressure/systemic blood pressure was significantly decreased in the castration group (31.3+/-15.7%, 18.6+/-4.6%) compared to the control group (58.0+/-11.4%, 58.9+/-8.2%) and testosterone replacement group (50.6+/-14.5%, 49.1+/-19.4%)(p<0.05). The expression of TGF-beta1 was increased at both 1 and 2 weeks of castration compared to the control group, and was down-regulated with testosterone replacement. CONCLUSIONS: These results suggest that the testosterone maintains erectile function and regulates the expression of TGF-beta1 in the rat penile corpus cavernosum.

Effect of Korean Red Ginseng on Vaginal Blood Flow and Structure in Hypercholesterolemic Female Rats / 대한남성과학회지

PURPOSE: The aims of this study were to investigate the effects of Korean Red Ginseng(KRG) on vaginal blood flow and histological changes in a hypercholesterolemic female rat model. MATERIALS AND METHODS: Female Sprague-Dawley rats were divided into two groups: the control(n=20) and the hypercholesterolemia(n=40). Hypercholesterolemia group was fed a high fat diet(2% cholesterol, 1% cholic acid, 5% coconut oil) for 12 weeks. The hypercholesterolemia group was further divided into the vehicle only and the KRG treatment(50 mg/kg/day) groups. After 4 and 8 weeks of treatment, vaginal blood flow was measured by a laser Doppler flowmeter. Vaginal tissues were processed for histology and Western blot. RESULTS: After 4 and 8 weeks of treatment, serum cholesterol levels(mg/dl) were significantly increased in the hypercholesterolemia group(1185.0+/-736.1, 934.3+/-212.3) compared with the control group(69.7+/-19.5, 67.1+/-7.2), and partially decreased in KRG treatment group(688.2+/-251.5, 694.2+/-150.4), respectively. Vaginal blood flow(ml/min/100 g tissue) after pelvic nerve stimulation was lower in the hypercholesterolemia group(17.3+/-7.9, 17.9+/-5.5) compared with the control group(27.3+/-17.1, 26.9+/-16.4), however, the KRG treatment group(29.5+/-10.3, 27.4+/-11.1) was as high as the control group, respectively. The expressions of TGF-beta1 tended to increase in the vagina of the hypercholesterolemia animals compared to those of the control and the KRG treatment groups. CONCLUSIONS: KRG treatment in hypercholesterolemic female rats decreased serum cholesterol levels and improved vaginal blood flow. These results suggest that KRG treatment may have a beneficial effect in women's sexual health.

Effects of Intracavernosal IGF-1 Gene Delivery on Erectile Function in the Aging Rat / 대한비뇨기과학회지

PURPOSE: Insulin like Growth Factor-1 (IGF-1) promotes the proliferation and migration of penile cavernous smooth muscle cells in rats. The goal of this study was to investigate the effects of an intracavernosal injection of the IGF-1 gene on the erectile function in the aging rat. MATERIALS AND METHODS: Corpus cavernosum smooth muscle cells (CCSMCs) were primarily cultured from Sprague-Dawley rats (16 wks). IGF-1 cDNA was subcloned into pcDNA3.1, and this expression plasmid transfected into CCSMCs. Two, three and four days after transfection, reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot analyses were carried out to quantify the transfection efficiency. In an in vivo study, male F344 rats (n=28) were divided into 2 groups; the young (5 months; n=7) and the old (20-21 months; n=21) groups. The old group was further divided into control (n=7) and treatment groups (n=14). The treatment group was given a single intracavernosal injection of DNA-liposome complex (pcDNA alone and pcDNA/IGF-1; 2mug or 4mug in 7 animals each). After 4 weeks of treatment, the erectile function and corpus cavernosal histology were evaluated by hemodynamic study and histomorphometric analysis, respectively. RESULTS: When the CCSMCs were transfected with IGF-1, the IGF-1 mRNA and protein were overexpressed compared to the control. After 4 weeks of treatment, the ratio of the peak intracavernosal pressure to systemic arterial pressure increased in the treatment group (66.3+/- 4.3% with 2mug, 65.4+/- 10.2% with 4mug), but without statistical significance (p>0.05) compared to the control group (55.5+/- 16.7%). The percentage of cavernosal smooth muscle also slightly increased in the treatment group (14.1+/-1.7% with 2mug), but without statistical significance (p>0.05) compared to the control group (13.2+/-1.2%). CONCLUSIONS: IGF-1 mRNA and IGF-1 protein were overexpressed in the rat corpus cavernosum smooth muscle cells due to IGF-1 gene delivery. However, lipid-mediated intracavernosal gene delivery of IGF-1 did not significantly improve the erectile function in the aging rat.

Effects of Insulin-Like Growth Factor-1 on Proliferation of Human Corpus Cavernosal Smooth Muscle Cells / 대한남성과학회지

PURPOSE: Insulin-like growth factor-1 (IGF-1) promotes the proliferation and migration of penile cavernous smooth muscle cells in the rat. The goals of this study were to evaluate the expression of IGF-1 and IGF-1 receptor (IGF-1R) in human corpus cavernosal smooth muscle cells (HCCSMCs) and to investigate the effect of IGF-1 on the proliferation of these cells in vitro. MATERIALS AND METHODS: The HCCSMCs were cultured from five impotent patients. The smooth muscle cells were identified by immunofluorescent stain. Total RNA was extracted, and IGF-1 gene expression was determined by RT-PCR. The IGF-1R immunoreactivity was examined by fluorescent Immunocytochemistry. Cell growth was assessed with a novel proliferation assay based on bioreduction of the fluorescent dye, Alamar blue. RESULTS: Endogenous IGF-1 mRNA expression was detected by RT-PCR analysis. The HCCSMCs were positive for IGF-IR. The proliferation of HCCSMCs increased with the dose in response IGF-1 in the culture medium in concentrations up to 100 ng/ml. CONCLUSIONS: Both IGF-1 and IGF-1R are expressed endogenously in human corpus cavernosal smooth muscle cells. IGF-1 promotes the proliferation of these cells in vitro.

Effects of Diabetes Mellitus on the Relaxation of Rabbit Vaginal Smooth Muscle / 대한비뇨기과학회지

PURPOSE: Diabetic women commonly reported decreased sexual arousal and a lack of vaginal lubrication. Genital arousal depends on the vaginal blood flow and the vaginal smooth muscle tone. The aim of this study was to investigate the effect of diabetes mellitus on the relaxation of the vaginal smooth muscles in the rabbit models. MATERIALS AND METHODS: New Zealand White female rabbits (3-3.5kg) were divided into two groups: control (n=5) and experimental (n=20). The experimental group received an intravenous injection of alloxan (100mg/kg). The development of diabetes was verified by measuring the body weight and blood glucose levels. After 12 weeks, the reactivity of the vaginal tissue from the control and diabetic animals was studied examined in the organ chambers. Vaginal The vaginal tissue was also processed immunohistochemically to determine the presence of the neuronal NOS isoform (n-NOS) in similar groups of rabbits. RESULTS: By After 12 weeks, five 5 of the 20 animals developed diabetes mellitus. The mean blood glucose level was significantly increased higher in the experimental group (340.8+/-116.9 mg/dl) compared to the control group (81.3+/-6.2mg/dl) (p=0.004). There was no significant difference in terms of the rRelaxation of vaginal tissue to electrical stimulation of the autonomic nerves, to the endothelium-dependent vasodilator acetylcholine and to the endothelium-independent vasodilator nitroprruside was not significantly different between the control and diabetic group. n-NOS immunoreactivity was also similar in both the control and diabetic groups. CONCLUSIONS: This The results suggest that diabetes mellitus may does not impair the neurogenic and endothelium-dependent relaxation of the rabbit vaginal smooth muscle. However, further intensive studies areinvestigation is needed to verify these results.

Effect of Intravesical BCG Instillation on the Expression of Inducible Nitric Oxide Synthase in Mouse / 대한비뇨기과학회지

PURPOSE: Bacillus Calmette-Guerin(BCG) therapy for superficial bladders carcinoma and carcinoma in situ is believed to exert its antitumor effects through immune mechanisms when BCG is instilled into the bladder, but its detail mechanisms are poorly understood. Recently, intravesical BCG instillation is known to induce nitric oxide(NO) which is revealed to be tumoricidal . This experiment was performed to determine the intravesical localization and alteration of expression of inducible nitric oxide synthase(iNOS) after BCG instillation. MATERIALS AND METHODS: Normal saline(0.85m1/kg, control group) and BCG(6mg/kg, experimental group) were instilled intravesically in fifty four female mice. After 2 hours, each mouse urinated after removal of urethral ligature, and was sacrificed at 6th, 12th, 18th hour, 1st day, 1.5th, 2th, 3th, 7th and 14th day, respectively. Immunohistochemistry was performed on paraffin embedded bladder tissue using anti-inducible NOS antibody(Transduction Labaratories, USA.). RESULTS: Inflammatory cells were infiltrated in the bladder wall in the BCG-treated group, but not in the control group. Number of inflammatory cells among BCG-treated group, was the highest in the 18th hour group and was reduced gradually with time elapse thereafter In the control group, immunoreactivity of iNOS to be positive in the all intermediate cell layer and a few basal cell layer of bladder transitional epithelium, which did not change as time passed. In the BCG-treated group, immunoreactivity of iNOS increased from 6 hours after BCG instillation, and gradually decreased from 7 days to restore to the level of the control group. However, some cells of transitional epithelium showed reduced immunoreactivity, focally. CONCLUSIONS: These results suggest that iNOS is tonically expressed in transitional epithelium of mouse bladder which is further induced by BCG instillation. Also, NOS-mediated NO production is supposed to be one of factors to induce tumoricidal erect by BCG instillation.