ABSTRACT
A Schwannoma is a tumor originating from the neural sheath of Schwann cells, and is also known as a neurilemmoma, neurinoma or fibroblastoma. It can be either a benign or malignant tumor arising from the associated nerve sheath. Here, a case of a Schwannoma, originated from the obturator nerve of the pelvic cavity, in a patient with urinary frequency is reported, with a brief review of the literature.
Subject(s)
Humans , Neurilemmoma , Obturator Nerve , Pelvis , Schwann CellsABSTRACT
PURPOSE: The inducible isoform of heme oxygenase(HO), HO-1, responds to hypoxia. HO-1 regulates vascular smooth muscle tone through carbon monoxide production. To investigate the possible role of HO-1 in low-flow priapism, we examined the expression and activity of HO-1 in artificially induced veno-occlusive priapism in rat. MATERIALS AND METHODS: Fourteen male Sprague Dawley rats were divided into 2 groups with 7 rats each. In the first group, low-flow priapism was induced using a vacuum-constriction device and a constriction rubber band; in the second group, low-flow priapism was induced using papaverine. We measured the expression level and activity of HO-1 in penile tissues after time periods of 0(control), 2, 3, 4, 8, 12, 24, and 48 hours. At the same time, the expression levels of i-NOS, e-NOS, and beta-actin(control) in penile tissues were also measured. RESULTS: In both groups, expression of HO-1 and HO-1 enzyme activities in penile tissue significantly increased in a time dependent fashion(p<0.01). However, there was no difference in the expression of i-NOS and e-NOS in both groups at any time period. CONCLUSIONS: HO-1 was induced over time in rats with artificially induced veno-occlusive priapism. Induction of HO-1 may play a protective role against hypoxic injury, but may also play an important role in the vicious cycle observed for low flow priapism. Increasing induction of HO-1 against hypoxic injury in a prolonged erectile state promotes sustained dilatation of corporal smooth muscle, and this may aggravate low-flow priapism.
Subject(s)
Animals , Humans , Male , Rats , Hypoxia , Carbon Monoxide , Constriction , Dilatation , Heme Oxygenase (Decyclizing) , Heme Oxygenase-1 , Heme , Muscle, Smooth , Muscle, Smooth, Vascular , Papaverine , Priapism , Rats, Sprague-Dawley , RubberABSTRACT
PURPOSE: Dopamine plays a critical role in promoting sexual drive and penile erection through dopamine receptors. This study was performed to investigate whether the cavernousal nerve controls the expression of peripheral dopamine D1 receptors in rat penile tissues after cavernousal nerve injury. MATERIALS AND METHODS: Male rats (n=20) were divided into two groups: a control group consisting of sham-operated rats (n=10) and an experimental group consisting of rats that underwent incision of the bilateral cavernous nerve (n=10). Three months later, the intracavernous pressure response was monitored using an intracavernous papaverine injection of 300 microgram. The expression of dopamine D1 receptor mRNA were studied using an RT-PCR method, and dopamine D1 receptor protein expression by Western blot analysis and immuno-histochemical staining in each group. The expressed band density of the RT-PCR and Western blot were measured by a densitometer. RESULTS: Erectile functions, as studied by intracavernosal papaverine injection at three months, were similar in both groups. The dopamine D1 receptor mRNA and protein expressions were significantly lower in the neurotomy group. The immuno-histochemical staining also showed a reduction in the dopamine D1 receptor expression in the neurotomy group compared with the control group. CONCLUSIONS: Our results show that dopamine D1 receptors in penile tissues were down-regulated following cavernousal nerve injury. These findings suggest that cavernousal nerve injury affects directly the reduction of dopamine D1 receptor expression, and that the action of dopamine on the cavernousal dopamine receptor will be affected in cavernousal nerve injured rats.