[Expressions of HO-2 and CO in the corpus cavernosum of castrated rats].

OBJECTIVE: To explore the expressions of HO-2 and CO in the corpus cavernosum of castrated rats in order to further study the pathogenesis of erectile dysfunction (ED). METHODS: We randomly divided 72 male SD rats into four groups: normal control, sham operation, castration, and castration + ZnPP. We detected intracavernous pressure (ICP) and penile erection in the basic condition and after apomorphine (APO) induction, determined the expression of the HO-2 protein in the corpus cavernosum by laser scanning confocal microscopy, and measured the level of CO by spectrophotometry during different periods of penile erection. RESULTS: The ICP in the basic condition and that after APO induction and the rate of penile erection were decreased significantly in the castration group ([11.68 ± 0.69] mmHg, [54.81 ± 3.86] mmHg, and 33.3%) and the castration + ZnPP group ([11.20 ± 0.71] mmHg, [41.17 ± 5.41] mmHg, and 22.2%) as compared with the normal control ([22.83 ± 2.66] mmHg, [66.92 ± 7.77] mm-Hg, and 100%) and the sham operation group ([23.35 ±2.22] mmHg, [70.43 ?7. 22] mmHg, and 100%) (all P <0. 01). After APO induction, ICP in the castration + ZnPP group was remarkably reduced in comparison with that in the castration group (P < 0.01), and so was the expression of the HO-2 protein before and during penile erection in the castration (445.4 ± 23.7 and 847.4 ± 35.0) and the castration + ZnPP group (390.1 ± 29.7 and 526.0 ± 52.5) compared with the normal control (512.7 ±57.4 and 1145.2 ± 89.8) and the sham operation group (583.7 ± 8.0 and 1016.3 ± 79.8), the expression of the HO-2 protein significantly decreased in the castration group (445.4 ± 23.7 and 847.4 ± 35.0) (P < 0.05 or 0.01), markedly lower in the castration + ZnPP than in the castration group during penile erection (P < 0.01) but with no significant differences among the four groups after it. Before, during and after penile erection, the levels of CO were remarkably decreased in the castration ([20.59 ± 1.01], [32.53 ± 1.26], and [18.71 ± 1.22] x 10(-7) nmol/L) and the castration +ZnPP group ([12.52 ± 1.05], [21.90 ± 1.02], and [16.56 ± 0.55] x 10(-7) nmol/L) as compared with the normal control ([26.76 ± 1.41], [48.25 ± 1.01], and [27.10 ± 1.58 ] x 10(-7) nmol/L) and the sham operation group ([25.41 ± 2.09], [ 47.90 ± 1.22], and [25.67 ± 1.20] x 10(-7) nmol/L) (P < 0.05 or 0.01), significantly lower in the castration + ZnPP than in the castration group during penile erection (P < 0.01). CONCLUSION: Decreased expressions of HO-2 and CO may correlate with erectile dysfunction in castrated rats.

[Correlation of carbon monoxide with cell apoptosis in the penile tissue of aging rats].

OBJECTIVE: To 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. METHODS: We 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. RESULTS: Cell 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). CONCLUSION: Cell 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.

[Effects of plasma Hcy on the contents of CO and HO-2 in the corpus cavernosum of ED rats with hyperhomocysteinemia].

OBJECTIVE: To study the changes in the activities of carbon monoxide (CO) and heme oxygenase 2 (HO-2) in ED rats with hyperhomocysteinemia (HHcy). METHODS: This study included 40 male Wistar rats weighing 280 - 310 g, 10 as normal controls (group A). HHcy models were made in the other 30 by giving 3% methionine for 4 weeks, and then divided into groups B, C and D. The rats in group B continued to be fed with 3% methionine, those in group C were treated with betaine hydrochloride, and those in group D were given zinc porphyrin IX at 45 micromol per kg per d. Penile erections of the rats were recorded, and 4 weeks later, all were killed for determination of the levels of homocysteine (Hcy) in the blood plasma and the activities of CO and HO-2 in the corpus cavernosum of the penis. RESULTS: The level of plasma Hcy, penile erection frequency and the content of CO in the corpus cavernosum were (12.55 +/- 0.82) micromol/L, (1.88 +/- 0.05) times and (10.55 +/- 1.73) micromol/L in group A, the Hcy level significantly higher while the penile erection frequency and CO content remarkably lower than in group B ([25.01 +/- 0.94] micromol/L, [0.70 +/- 0.05] times and [9.51 +/- 1.52] micromol/L, P < 0.05 or P < 0.01), with a negative correlation between the level of Hcy and that of CO and HO-2 (P < 0.01). Compared with group B, the three parameters were all significantly increased in C ([14.37 +/- 0.47] micromol/L, [1.18 +/- 0.08] times and [10.36 +/- 1.56] micromol/L, all P < 0.05 or P < 0.01). CONCLUSION: Decreased expressions of CO and HO-2 in the corpus cavernosum of the penis may result in ED in HHcy rats. Betaine can reduce the Hcy level in the blood plasma and CO content in the corpus cavernosum, which might be one of the mechanisms of its action on ED with HHcy.

[Nicotine reduces endogenous CO concentration and NOS activity in rat corpus cavernosum].

OBJECTIVE: To observe the effects of nicotine on endogenous carbon monoxide (CO) concentration and nitric oxide synthase (NOS) activity in the corpus cavernosum of adult male rats, and explore the possible mechanism of cigarette smoking affecting erectile dysfunction. METHODS: Forty adult male rats were equally divided into three treatment groups to receive subcutaneous injection of nicotine at 0.5 mg/kg pre d for 1, 2 and 3 months, and a control group to receive saline only. After treatment, the corpus cavernosum was harvested for detection of CO concentration by modified two-wavelength spectrophotometry and NOS activity by improved Griess measurement. RESULTS: CO concentration and NOS activity were decreased by 9.05 and 13.37%, respectively, after 1 month of nicotine injection (P < 0.01), 16.47 and 22.5% after 2 months (P < 0.01), and 22.99 and 31.74% after 3 months (P < 0.01), as compared with (13.664 +/- 0.404) umol/mg prot and (9.721 +/- 0.470) U/mg prot in the control group. CONCLUSION: Nicotine can reduce endogenous CO concentration and NOS activity in the corpus cavernosum of adult male rats, which suggests the involvement of endogenous CO and NOS in the pathophysiological process of smoking-induced erectile dysfunction .

[Correlation of homocysteine in plasma with NOS and endogenous CO in the penile corpus cavernosum of type 2 diabetic rats].

OBJECTIVE: To study the correlation of homocysteine (Hcy) in plasma with nitric oxide synthetase (NOS) and endogenous carbon monoxide (CO) in the penile corpus cavernosum of type 2 diabetic rats. METHODS: This study included 40 male Wistar rats, 10 as controls (Group A) and the other 30 as diabetes mellitus (DM) models. Four weeks after the model establishment, the model rats were divided into a DM group (Group B, n = 10), an insulin treated group (Group C, n = 10), and a folic acid and vitamin B12 treated group (Group D, n = 10). All the rats were injected with apomorphine and observed for penile erection at 8 and 12 weeks, and the levels of total plasma Hcy (tHcy), NOS and CO in the penile corpus cavernosum were measured at 12 weeks. RESULTS: Compared with Group A, the level of tHcy was significantly increased, while NOS and CO activities in the penile cavernous tis-sue and erectile function remarkably decreased in Group B (P < 0.01). The incidence rate of high Hcy was 55% in the DM rats. In comparison, the level of tHcy was obviously decreased, and the NOS activity and erectile function markedly increased in Groups C and D (P < 0.01). The Hcy level showed a significant negative correlation with NOS activity (rA = -0.89, rB = -0.76, rc = -0.91, rD = -0.91) and CO content (TA = -0.82, r, = -0.77, rc = -0.93, rD = -0.81). CONCLUSION: High plasma Hcy can decrease NOS and CO activities in the penile corpus cavernosum, and consequently induce erectile dysfunction in DM rats, while insulin, folic acid and vitamin B12 can improve their penile erectile function by increasing NOS and CO activities.

[ZnPP IX and L-NAME reduce the cGMP content in the penile tissue of rats].

OBJECTIVE: To investigate the effects of CO release inhibitor zinc protoporphyria IX (ZnPP IX) and NO release inhibitor L-NAME on the content of cGMP in the penile tissue of rats. METHODS: Thirty Wistar rats were randomly divided into a normal control, a ZnPP IX, and an L-NAME group, given saline (1 ml/kg/d), ZnPP IX (45 micromol/kg/d) and L-NAME (50 mg/kg/d), respectively, for 7 days. Then all the rats were killed, homogenate made from their penile tissues and detected for the contents of NOS, NO, CO and cGMP. RESULTS: The contents of CO, NOS, NO and cGMP were all reduced in both the ZnPP IX and L-NAME groups as compared with the control group (P < 0.05). CONCLUSION: ZnPP IX and L-NAME can reduce the concentrations of CO and NO in the penile tissues of rats, and consequently the content of cGMP.

[Effect of thyroid hormone on the contents of NOS and CO in the penile corpus cavernosum of rats].

OBJECTIVE: To determine the contents of NOS and endogenous CO in the penile corpus cavernosum of Wistar rat models of hyperthyroid and hypothyroid, to detect the effects of thyroid hormone and endogenous CO on rat penile erection, and to further investigate the influence of thyroid hormone on human penile erection. METHODS: Fifty 3-month-old male Wistar rats were randomly and equally divided into 5 groups: a hyperthyroid, a hyperthyroid treatment, a hypothyroid, a hypothyroid treatment and a control group. The contents of NOS and CO were detected by ultraviolet spectrophotometry. RESULTS: Compared with the controls, the content of NOS was significantly decreased in both the hyperthyroid and the hypothyroid groups (P < 0.01), even lower in the latter than in the former (P < 0.01), and so was the content of CO (P < 0.01), lower in the former than in the latter (P < 0.01). After treatment, the levels of NOS and CO were both elevated in either the hyperthyroid or the hypothyroid group, with no significant difference from that of the controls (P > 0.05). CONCLUSION: The contents of NOS and CO in the penile corpus cavernosum decrease with the imbalance of thyroid hormones, but return to normal once the imbalance is corrected. Under the same conditions, hypothyroid inflicts more damage on penile erection than hyperthyroid.

[Aging reduces contents of endogenous CO, cAMP and cGMP in rat penile tissues].

OBJECTIVE: To explore the relationship of aging with the changes of endogenous carbon monoxide (CO), cGMP and cAMP contents in the penile tissues of rats. METHODS: Twenty-four male rats were equally divided into an 8-month, a 16-month and a 24-month group, and their penile erection was detected by injecting apomorphine, their penile cavernous body harvested, and the contents of CO, cAPM and cGMP detected by improved dual wavelength spectrophotometry. RESULTS: The contents of CO, cAPM and cGMP were reduced with the increase of age, with statistically significant differences between the three age groups (P < 0.01). CONCLUSION: Aging significantly decreased the contents of CO, cAMP and cGMP in the penile tissues of the rats, which suggests that aging might play an important role in erectile dysfunction.

[Intervention effect of ganoderma lucidum spores on the changes of XOD, MPO and SDH in the testis tissue of NIDDM rats].

OBJECTIVE: To investigate the changes of xanthine oxidase (XOD), myeloperoxidase (MPO) and mitochondrial succinate dehydrogenase (SDH) in the testis and the protective effect of ganoderma lucidum spores on the testicular tissue of rats with non-insu- lin-dependent diabetes mellitus (NIDDM). METHODS: Fifty male Wistar rats were divided randomly into a model, a ganoderma and a normal control group, the first two groups injected with 2% STZ (25 mg/kg) through the peritoneum, and the last one with half-and-half sodium citrate/citrate buffer solution. Two weeks after normal diet, glucose tolerance tests were performed and the rats with abnormal glucose tolerance in the model and ganoderma groups received high-fat and high-carbohydrate food, the latter given ganoderma lycium spores (250 mg/kg x d) in addition, both for 10 weeks and all rats fed alone. Glucose tolerance tests were repeated 1 day before the end of the experiment and the testes of the rats were harvested for the determination of XOD, MPO and SDH. RESULTS: SDH was significantly lower (P < 0.05) while XOD and MPO significantly higher in the model group than in the ganoderma and control groups (P < 0.05). The model rats exhibited abnormal convoluted seminiferous tubules, indistinct parietal layers, decreased or abolished gonepoiesis, luminal peripheral fibrous tissue (interstitial substance) accrementition, basal lamina thickening, and vessel wall fibrous tissue accrementition and sclerosis. CONCLUSION: Ganoderma lucidum spores can protect the testis of diabetic rats by reducing free radical-induced damage to the testicular tissue and enhancing the activity of SDH.

[Nitric oxide synthetase and carbon monoxide decrease in the penile corpus cavernous of hyper homocysteine rats].

OBJECTIVE: To detect the levels of nitric oxide synthetase (NOS) and carbon monoxide (CO) in the penile corpus cavernous of adult male Wistar rats with high homocysteine (Hhcy) and to explore the relationship of NOS and CO levels with erectile dysfunction. METHODS: Twenty Wistar rats were equally and randomly divided into a control and an Hhcy group and fed on normal diet and normal diet with 3.0% methionine respectively. Four weeks later, the levels of NOS and CO in the penile corpus cavernous were detected by ultraviolet spectrophotometry and that of serum homocysteine by the cycle enzyme method. RESULTS: Compared with the control group, the levels of NOS and CO in the penile corpus cavernous were significantly lower in the Hhcy group, (6.45 +/- 1.12) nmol/(g x min) vs (10.77 +/- 0.60) nmol/(g x min) and (10.60 +/- 0.92) micromol/L vs (13.36 +/- 0.44) micromol/L, while that of homocysteine was significantly higher, (22.32 +/- 1.65) micromol/L) vs (4.90 +/- 1.73) micromol/L. CONCLUSION: Four-week diet with methionine can cause Hhcy and significantly decreased levels of NOS and CO in the penile corpus cavernous in Wistar rats. Hhcy is an independent risk factor of erectile dysfunction.

[Effect of endogenous carbon monoxide on the smooth muscle function of dog penile corpus cavernosum in vitro].

OBJECTIVE: To study the effect of endogenous carbon monoxide (CO) on the smooth muscle function of the dog penile corpus cavernosum in vitro. METHODS: Tissue bioassay was used to measure the corpus cavernosum muscle contraction and relaxation. The production of CO was induced in the corpus cavernosum smooth muscle, and the effect of CO on the penile corpus cavernosum smooth muscle pre-contracted by phenylephrine (PE) was determined. RESULTS: Chlorinous hemoglobin could relax the smooth muscle stripes pre-contracted by 10 micromol/L PE. A dose-dependent relaxation was observed. The relaxation responses by 10 -100 micromol/L chlorinous hemoglobin were significant compared with the control group (P < 0. 01). The pretreatment of the muscle stripes with ZnPP-IX or methylthioninium significantly reduced the relaxing effect of chlorinous hemoglobin (P < 0.01). CONCLUSION: The relaxing effect of endogenous CO on the smooth muscle of the penile corpus cavernosum depends on the concentration of endogenous CO. The underlying mechanism may involve the pathway from CO to cGMP production.

[Effects of ganoderma lucidum spores on cytochrome C and mitochondrial calcium in the testis of NIDDM rats].

OBJECTIVE: To observe the effects of Ganoderma lucidum spores on Cytochrome C (Cyt-C) and mitochondrial calcium in the testis of NIDDM rats. METHODS: Fifty male Wistar rats were divided randomly into three groups: model, ganoderma and normal control, the first two groups injected with 2% STZ through vena caudalis, and the last one with half-and-half sodium citrate/citrate buffer solution. Two weeks after normal diet, glucose tolerance tests were performed and the rats with abnormal glucose tolerance from the model and ganoderma groups received high-fat and high-carbohydrate food, the ganoderma group given Ganoderma lucidum spores (250mg/[ kg x d] ) in addition, both for 10 weeks. Glucose tolerance tests were repeated 1 day before the end of the experiment and the rats were castrated and relevant indexes measured. RESULTS: The NIDDM model was successfully constructed. In the model group, the levels of mitochondrial Cyt-C and mitochondrial calcium were significantly lower (P <0. 05) while that of the plasma Cyt-C was significantly higher than in the ganoderma and the control groups. CONCLUSION: Cyt-C and calcium ion are involved in the damage of the testis. Ganoderma lucidum spores can protect the testis of NIDDM rats.