Platelet-rich plasma (PRP) shows promise as a regenerative modality for mild-to-moderate erectile dysfunction (ED). However, its efficacy in treating severe ED remains unknown. Blood samples from 8-week-old male rats were used to prepare PRP through a two-step centrifugation procedure, followed by chitosan activation and freeze thaw cycle. A hyperhomocysteinemia (HHcy)-related ED model was established using a methionine-enriched diet, and an apomorphine (APO) test was conducted during the 4 th week. APO-negative rats were divided into two groups and were injected with PRP or saline every 2 weeks. Erectile function and histological analyses of the corpus cavernosum were performed during the 16 th week. The results revealed that erectile function was significantly impaired in rats with HHcy-related ED compared to that in age-matched rats but was improved by repeated PRP injections. Immunofluorescence staining revealed a reduction in reactive oxygen species and additional benefits on the recovery of structures within the corpus cavernosum in rats that received PRP treatment compared to those in the saline-injected control group. Therefore, PRP could enhance functional and structural recovery in a severe HHcy-related ED model. A notable strength of the present study lies in the use of a repeated intracavernous injection method, mirroring protocols used in human studies, which offers more reliable results for translating the findings to humans.
Animals ; Male ; Platelet-Rich Plasma ; Hyperhomocysteinemia/complications* ; Erectile Dysfunction/etiology* ; Rats ; Disease Models, Animal ; Penis ; Rats, Sprague-Dawley ; Reactive Oxygen Species/metabolism* ; Penile Erection/physiology* ; Apomorphine/administration & dosage*

OBJECTIVETo discuss the protective effect of alkaloids from Piper longum (PLA) in rat dopaminergic neuron injury of 6-OHDA-induced Parkinson's disease and its possible mechanism.

METHODThe rat PD model was established by injecting 6-OHDA into the unilateral striatum with a brain solid positioner. The PD rats were divided into the PLA group (50 mg x kg(-1) x d(-1)), the madorpa group (50 mg x kg(-1) x d(-1)) and the model group, with 15 rats in each group. All of the rats were orally given drugs once a day for 6 weeks. Meanwhile, other 15 rats were randomly selected as the sham operation group, and only injected with normal saline in the unilateral striatum. The behavioral changes were observed with the apomorphine (APO)-induced rotation and rotary rod tests. The number of tyrosine hydroxylase (TH)-positive cells in rat substantia nigra and the density of TH-positive fibers in striatum were detected by tyrosine hydroxylase immunohistochemistry. The content of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione (GSH), catalase (CAT), malondialdehyde (MDA), nitric oxide (NO) and nitric oxide synthase (NOS) in rat substantia nigra and striatum were measured by the spectrophotometric method.

RESULTAfter being induced by APO, PD rats showed obvious rotation behaviors, with decreased time stay on rotary rod and significant reduction in the number of TH-positive cells in sustantia nigra and the density of TH-positive fibers in striatum. The activities of SOD, GSH-Px, CAT, the content of GSH and the total antioxidant capacity significantly decreased, whereas the activities of NOS and the content of MDA, NO significantly increased. PLA could significantly improve the behavioral abnormality of PD rats and increase the number of TH-positive cells in sustantia nigra and the density of TH-positive fibers in striatum. It could up-regulate the activities of SOD, GSH-Px, CAT, the content of GSH and the total antioxidant capacity, and decrease the content of NOS and the content of MDA, NO.

CONCLUSIONAlkaloids from P. longum shows the protective effect in substantia nigra cells of 6-OHDA-induced PD model rats. Its mechanism may be related with their antioxidant activity.

Administration, Oral ; Alkaloids ; administration & dosage ; pharmacology ; Animals ; Apomorphine ; pharmacology ; Catalase ; metabolism ; Dopamine Agonists ; pharmacology ; Dopaminergic Neurons ; drug effects ; metabolism ; pathology ; Glutathione ; metabolism ; Glutathione Peroxidase ; metabolism ; Male ; Malondialdehyde ; metabolism ; Motor Activity ; drug effects ; Neostriatum ; drug effects ; metabolism ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; metabolism ; Oxidopamine ; Parkinson Disease, Secondary ; chemically induced ; physiopathology ; prevention & control ; Piper ; chemistry ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Substantia Nigra ; drug effects ; metabolism ; Superoxide Dismutase ; metabolism ; Tyrosine 3-Monooxygenase ; metabolism

OBJECTIVETo study the changes of morphology and erectile function of the cavernous tissues in spontaneously hypertensive rats.

METHODSSpontaneously hypertensive male rats (SHR) (n = 15) and normotensive Wistar-Kyoto rats (WKY) (n = 15) were studied for 20 weeks. Systolic blood pressure (SBP) was measured weekly by the tail/cuff method. Erectile function was tested by injecting apomorphine (APO). The expression alpha-smooth muscle actin (alpha-SMA) and collagen III was examined by immunohistochemistry.

RESULTSSHR showed a higher systolic blood pressure (205.7 +/- 11.9 vs 114.3 +/- 10.2 mm Hg) and a lower erection frequency (0.6 +/- 0.5 vs 2.4 +/- 0.6). The expression of alpha-smooth muscle actin and collagen III in the cavernous tissues in the SHR was significantly higher than in the WKY.

CONCLUSIONThe erectile function of the penis is markedly affected by hypertension, and the pathological changes may be one of the most important mechanisms of decreased erectile function in SHR.

Actins ; biosynthesis ; Animals ; Apomorphine ; administration & dosage ; Blood Pressure ; physiology ; Collagen Type III ; biosynthesis ; Hypertension ; pathology ; physiopathology ; Immunohistochemistry ; Male ; Penile Erection ; physiology ; Penis ; metabolism ; pathology ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY

PURPOSE: The aim of this study was to demonstrate that the combined systemic administration of apomorphine (APO) and sildenafil have a synergistic effect on the erection in conscious rabbits. MATERIALS AND METHODS: The erections of the male New Zealand White rabbits (2-3kg, n=12) were assessed by measuring the length of the uncovered penile mucosa (LUPM) and duration of the erection, both before and after the intravenous administration of agents. After the injection of APO (0, 0.05, 0.1, 0.4mg/kg), sildenafil was administered intravenously in a dose-response manner (0.5, 1, 5mg/kg), followed by measurements for 0-120 minutes. In additional experiments, the effect of increasing the dosages of sildenafil, combined with APO, on blood pressure were evaluated. RESULTS: The intravenous administration of sildenafil caused a concentration dependent increase in the LUPM. There was a statistically significant increase in the LUPM with the administration of APO compared with no administration. The dosages of sildenafil and APO showing the greatest efficacy of sildenafil potentiation were 1mg/kg and 0.1 mg/kg, respectively. The intravenous administration of APO at a dose of 0.1mg/kg was more effective than those of 0.05 and 0.4mg/kg, with dosages of sildenafil of 0.5 and 1mg/kg. There was no additional increase in the duration of erection on the administration of APO. The intravenous administration of sildenafil caused a concentration dependent decrease in blood pressure, but there was no additional decrease on administration of the APO. CONCLUSIONS: We have shown that apomorphine elicits a stronger response on the erection induced by sildenafil in conscious rabbits, with no additional decrease in blood pressure.
Administration, Intravenous ; Apomorphine* ; Blood Pressure ; Humans ; Male ; Mucous Membrane ; Penile Erection* ; Rabbits* ; Sildenafil Citrate