The possible protective effects of dipyridamole on ischemic reperfusion injury of priapism

An Experimental Rat Model Study: Is There Any Effect of Syringic Acid on Ischemia-Reperfusion Injury in Priapism?

Purpose The purpose of this research is to examine the impact of syringic acid on ischemia-reperfusion injury in cavernosal tissue, utilizing a rat model of induced priapism. Materials and methods A total of 24 rats were allocated into three groups. Group 1 was designated as the control group, while Group 2 underwent ischemia-reperfusion injury assessment using the priapism model. Group 3 underwent the same procedures as Group 2, with the addition of intraperitoneal administration of syringic acid (100 mg/kg) 60 min after priapism initiation. All rats underwent penectomy, and sufficient blood samples were collected. Histopathological assessment of penile cavernosal tissue involved grading tissue damage, inflammation, vasocongestion, desquamation, and edema on a scale of 0-3 (0: normal, 1: mild, 2: moderate, 3: severe). Result Significant differences were observed among the three groups in terms of IL-1 beta and TNF-alpha levels (p=0.001 and p<0.001, respectively). IL-1 beta and TNF-alpha levels in Group 2 were found to be significantly higher than Group 3 (p=0.003 and p=0.004). There was also a significant difference among the three groups in terms of median MDA levels (p<0.001). Furthermore, the median MDA level in Group 2 was found to be significantly higher than that in Group 3 (p<0.001). While significant differences were observed among the three groups in terms of median SOD and GSH-px levels, no significant difference was found among the groups in terms of median PC levels (p=0.004, p= 0.048, and p=0.159, respectively). In direct microscopic examination, a significant improvement in pathological scores was noted in Group 3 compared to Group 2 (p<0.001). Conclusion Syringic acid demonstrated protective properties against ischemia-reperfusion injury caused by priapism in cavernosal tissue.

Priapism or Prolonged Erection: Is 4 - 6 Hours of Cavernous Ischemia the Time Point of Irreversible Tissue Injury?

INTRODUCTION

Ischemic priapism remains a significant cause of morbidity among men. To date, the precise time when penile ischemia results in permanent, non-reversible cavernosal smooth muscle injury, compromising subsequent erectile integrity, remains ill-defined.

OBJECTIVES

To review the medical literature pertaining to ischemic priapism, focusing on factors that predict the exact timeline of irreversible cavernous tissue injury.

METHODS

A comprehensive literature search was performed. Our search included both publications on animal models and retrospective clinical series through January 2022. Articles were eligible for inclusion if they contained original data regarding nonreversible tissue injury on histology and/or provided a timeline of erectile function loss or preservation and had full text available in English.

RESULTS

Innovative studies in the 1990s using invitro models with strips of rabbit, rat, canine and monkey corpus cavernosal tissue demonstrated that anoxia eliminated spontaneous contractile activity and reduced tissue responsiveness to electrical field stimulation or pharmacological agents. The same models demonstrated that the inhibitory effects of field stimulated relaxation, were mediated by nitric oxide. Subsequent studies using similar models demonstrated that exposure of corpus cavernosum smooth muscle to an acidotic environment impairs its ability to contract. A pH of 6.9 was chosen for these experiments based on a case series of men with priapism, in whom a mean pH of 6.9 was measured in corporal blood after 4-6 hours of priapism. Invivo animal studies demonstrated that after erection periods of 6-8 hours, microscopy shows sporadic endothelial defects but otherwise normal cavernous smooth muscle. In these studies, greater durations of ischemic priapism were shown to result in more pronounced ultrastructural changes and presumably irreversibility. In studies involving human corporal tissues, samples were obtained from men who had experienced priapism for at least 12 hours. Overall, erectile function outcome data is deficient in priapism reporting, especially within treatment windows less than 6 hours. Some reports on ischemic priapism have documented good erectile function outcomes with reversal by 12 hours.

CONCLUSION

Based on our extensive review of animal models and clinical reports, we found that many clinical papers rely on the same small set of animal studies to suggest the time point of irreversible ischemic damage at 4-6 hours. Our review suggests an equal number of retrospective clinical studies demonstrate that ischemic priapism reversed within 6-12 hours may preserve erectile function in many patients. Dekalo S, Stern N, Broderick GA, et al. Priapism or Prolonged Erection: Is 4 - 6 Hours of Cavernous Ischemia the Time Point of Irreversible Tissue Injury? Sex Med Rev 2022;XX:XXX-XXX.

Protective effects of hydrogen rich saline solution on ventral penile mathieu type flap with penile tourniquet application in rats

INTRODUCTION

Penile tourniquet (Pt) application aims to work in a bloodless field in penile surgery. When the tourniquet is released, reperfusion injury occurs with the resumption of blood flow. Molecular hydrogen can easily attach to biomembranes and enter cytosol, mitochondria and other organelles of the cell and convert the formed OH- to H₂O to prevent cell and tissue damage.

AIM

We investigated the effects of hydrogen rich saline solution (HRSS) on penile Mathieu type flap tissue with Pt application in rats.

STUDY DESIGN

Thirty-six Wistar-albino male rats were randomly divided into six groups. No operations were performed in the Sham group. Ventral penile Mathieu type flap was prepared and Pt was applied to the root of the penis with a plastic band in other groups. Pt was applied 10 and 30 min in the PT¹⁰ and PT³⁰ groups. HRSS was injected intraperitoneally (ip) 5 ml/kg just before Pt was released in the HRSS¹⁰ and HRSS³⁰ groups. In the HRSS^B group, HRSS was injected 1 h before 10 min of Pt application. At the 4th hour of experiments the rats were sacrificed and tissue samples were taken for biochemical and histopathological studies. Tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), myeloperoxidase (MPO), malondialdehyde (MDA) and glutathione (GSH) levels were determined in the penile tissue. The results were analyzed with one-way ANOVA and Pearson's Chi-Squared test.

RESULTS

Tissue MDA, MPO, IL-6 and TNF-α values were significantly lower in all HRSS groups compared to PT¹⁰ and PT³⁰ groups. Tissue GSH levels of HRSS groups were higher compared to PT groups. Histopathologically, inflammation was found to be higher in PT groups compared to HRSS groups. Interestingly, in the HRSS^B group with HRSS administration prior to Pt, the damage was less in grade, but not statistically different than the other HRSS groups (p > 0.05).

DISCUSSION

In previous studies, damage in histopathological examinations after Pt could only be demonstrated long after tourniquet applications such as 24 h and with longer duration of Pt such as 30 min. Structural changes in different Pt application times could be demonstrated at 60 min by electron microscopy and 48 h by light microscopy. In this study, the histopathological effect of Pt application could be demonstrated at the 4th hour after release and HRSS was observed to reduce the damage histopathologically as well as biochemically with its anti-inflammatory and antioxidant effects. It was observed that administration of HRSS either before or following Pt did not cause an alteration statistically.

CONCLUSION

HRSS reduces tissue oxidative stress and inflammation on the flap tissue and has a protective effect in Pt applied to the hypospadias model created with a penile flap.

Protective effects of dexmedetomidine on ischaemia-reperfusion injury in an experimental rat model of priapism

The study aimed to investigate the effects of dexmedetomidine against ischaemia-reperfusion injury occurring after priapism in a model of induced-priapism in rats. A total of 18 male rats were randomised into three groups. Group 1 was the control group. A priapism model was performed rats in Group 2 and then ischaemia-reperfusion injury was evaluated. Group 3 had similar procedures to the rats in Group 2. Rats in Group 3 additionally had 100 μg/kg dexmedetomidine administered intraperitoneally immediately after reperfusion. Blood and tissue samples were analysed. Biochemical analysis of blood samples revealed a decrease in the levels of the pro-inflammatory cytokines including interleukin-1 beta (IL-1 Beta), interleukin-6 (IL-6), and tumour necrosis factor-alpha (TNF-alpha) in Group 3 compared to Group 2 (p:.04, p:.009 and p:.009, respectively). Similarly, the highest malondialdehyde (MDA) level was in Group 2 (p:.002). The levels of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were significantly higher in Group 3 than that of Group 2 (p:.037 and p:.045, respectively). Direct microscopic examinations revealed positive changes in desquamation, oedema, inflammation and vasocongestion scores in Group 3 compared to Group 2 (p:.007, p:.008, p:.007 and p:.006, respectively). Dexmedetomidine has a protective effect against ischaemia-reperfusion injury in penile tissue.

The effects of oxytocin on penile tissues in experimental priapism model in rats

PURPOSE

This study aimed to demonstrate the effects of oxytocin on penile tissues in ischemia-reperfusion injury developed after priapism.

METHODS

Forty Wistar Albino strain male rats were divided into four groups. The control group (n = 10) was not intervened. In Group 2, a rat model of priapism was constructed and maintained for 1 h. In Group 3, reperfusion was ensured for 30 min following priapism. Rats in Group 4 rats were given oxytocin 30 min before the induction of reperfusion following priapism. All rats were penectomized, and adequate amounts of blood sample were drawn. Inflammation, vasocongestion, desquamation, and edema in penile tissue were scored between 0 and 3 points (0: normal, 1: mild, 2: moderate, 3: severe) to evaluate the severity of tissue damage. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the levels of malondialdehyde (MDA), and nitric oxide (NO) in blood samples were determined spectrophotometrically.

RESULTS

In histopathological examination, statistically significant positive changes were detected in vasocongestion, inflammation, desquamation, and edema scores in Group 4 than in Group 2 and Group 3 (p < 0.001). Biochemical test results revealed that NO levels were significantly lower in Group 4 than in Group 3 (p < 0.001). Serum GSH-Px activities in Group 4 significantly increased when compared with the other groups 2 and 3 (p = 0.002, p = 0.001, respectively). There was no statistical difference among the groups regarding SOD activities and MDA levels (p > 0.05).

CONCLUSIONS

Oxytocin protected against priapism-induced ischemia-reperfusion injury developed in cavernosal tissue as observed based on histopathological and biochemical evidence. Although this is an experimental study, oxytocin can be thought as an alternative drug in the treatment of priapism.

The Case Report of Priapus and a Modern Approach to an Ancient Affliction

INTRODUCTION

Priapism, taking its name from God Priapus, is total or partial erection lasting longer than 4 hours independent of sexual stimulus and can result in erectile dysfunction. There are three subtypes of priapism.

AIM

To review the three subtypes of priapism, their pathophysiology, current treatment options, and complications.

METHODS

The literature including priapism guidelines, review articles, and current trial studies was reviewed and the priapism type of God Priapus was investigated according to the mythology.

MAIN OUTCOME MEASURES

All three types of priapism were reviewed for etiology, diagnosis, and management. Medical and surgical treatment options were reviewed in relation to the current literature. Special emphasis concerned current treatment strategies and controversial surgical topics.

RESULTS

Ischemic priapism is the most common type, constituting 95% of all cases, and is an emergency. First-line treatments are blood aspiration and intracavernosal sympathomimetic drug injections. If these fail, then surgical shunt operations are recommended. A T-shunt combined with corporal tunneling is the currently popular option. Immediate penile prosthesis implantation is recommended for patients who present 48 to 72 hours after the onset of a priapism episode. High-flow priapism is caused by irregular arterial cavernosal blood flow, which usually occurs after a blunt perineal trauma. Antiandrogens and selective arterial embolization are the treatment options. Stuttering priapism is repetitive, self-limiting ischemic priapism and frequent in patients with sickle cell anemia. Ketoconazole is safe, cheap, and effective and appears to be a logical and suitable current treatment option to prevent further episodes, which is the primary treatment goal of stuttering priapism.

CONCLUSION

Priapism is a relatively common condition but not well known by clinicians. The lack and delay of treatment result in irreversible complications such as erectile dysfunction. Each type of priapism should be diagnosed and treated correctly with caution.