Cavernosal Tissue (cavernosal + tissue)

Distribution by Scientific Domains


Selected Abstracts


Does Erectile Tissue Angioarchitecture Modify with Aging?

THE JOURNAL OF SEXUAL MEDICINE, Issue 4 2008
An Immunohistological, Morphometric Approach
ABSTRACT Introduction., Erectile dysfunction is a common problem in aged men; however, which vascular cavernosal alterations occur with age progression remain unclarified. Aim., Using cavernosal tissue from rats of various ages, we aimed to thoroughly assess erectile vascular-associated morphologic, immunohistological, and morphometric alterations during aging. Methods., Male Wistar rats were divided according to age in groups of 2, 6, 12, 18, 24 months old (N = 5). Cavernosal tissue of all groups was collected and processed for morphologic evaluation, immunodetection of ,-smooth muscle actin and von Willebrand factor and morphometric quantification of vascular and smooth muscle cell (SMC) areas. Main Outcome Measures., The morphometric assessment of age-related alterations in cavernosal vascular and SMCs using the ImageJ image-processing program. Results., Morphologic and immunohistological evaluation showed a similar structure of erectile tissue among all age groups, divided in two cavernosal bodies containing numerous sinusoidal vascular spaces surrounded by SMCs. Additionally, we observed a reduction of SMC content and an increase in the caliber of vascular spaces, with aging. This was confirmed by the morphometric quantification of the vascular and SMC areas (mean area ×103 µm2 ± ×103 standard error). Two-month-old animals had a mean vascular area of 4.21 ± 0.51, approximately 3.5-fold less than the 6-month-old group. The differences increased when comparing the youngest groups with the 12-, 18-, and 24-month-old animals, with mean measurements of 18.99 ± 1.91, 25.23 ± 2.76, and 26.34 ± 2.97. Conversely, SMC areas progressively decreased between 2- and 6-month-old animals, from 6.75 ± 0.90 to 6.38 ± 1.24. The elderly 12-, 18-, and 24-month-old groups presented an approximated 1.5-fold reduction on SMCs area, showed by the respective measurements of 4.11 ± 0.50, 4.01 ± 0.35, and 4.02 ± 0.44. Conclusions., We demonstrated that cavernosal angioarchitecture was modified with aging. The decrease in SMCs and the considerable enlargement of vascular lumens may limit the basic function of penile vascular tree in the elderly. Costa C, and Vendeira P. Does erectile tissue angioarchitecture modify with aging? An immunohistological and morphometric approach. J Sex Med 2008;5:833,840. [source]


The Effect of Hyperbaric Oxygen Therapy on Erectile Function Recovery in a Rat Cavernous Nerve Injury Model

THE JOURNAL OF SEXUAL MEDICINE, Issue 3 2008
Alexander Müller MD
ABSTRACT Introduction., Cavernosal oxygenation appears to be important for preservation of erectile tissue health. Hyperbaric oxygen therapy (HBOT) has been shown to improve tissue oxygenation and has neuromodulatory effects. Aim., This study was designed to define the effects of HBOT on erectile function (EF) and cavernosal tissue in the rat cavernous nerve (CN) injury model. Methods., Four groups of Sprague-Dawley rats were studied: rats with bilateral CN crush, HBOT treated (Crush+/HBOT+); bilateral CN-crush/no HBOT (C+/H,); no crush/no HBOT (C,/H,); and no crush/HBOT (C,/H+). HBOT was delivered daily for 90 minutes at three atmospheres for 10 days commencing the day of CN crush. Main Outcome Measures., Ten days after CN injury, the animals underwent CN stimulation measuring the maximal intracavernosal pressure/mean arterial pressure (ICP/MAP) ratios. Corporal tissue was harvested pre-sacrifice, and immunohistochemically stained for nerve growth factor (NGF), endothelial nitric oxide synthase (eNOS), and cluster of differentiation molecule (CD31). Histologic analysis was performed for Masson's trichrome to assess the smooth muscle,collagen ratio. Terminal deoxynucleotidyl transferase Biotin-dUTP Nick End Labeling assay was used to define apoptotic indices (AIs). Results., The C+/H, group had significantly lower ICP/MAP ratios compared with C,/H, rats, (31% vs. 70%, P < 0.001). C+/H+ rats had significantly higher ICP/MAP ratio recovery compared with the C+/H, group (55% vs. 31%, P = 0.005). NGF and eNOS staining densities were higher in C+/H+ rats compared with C+/H, rats (P < 0.05 and P < 0.001, respectively). No difference was seen in CD31 expression. Staining density for MT displayed a trend toward higher smooth muscle preservation after HBOT. AIs were significantly increased by HBOT (P < 0.05). Conclusion., HBOT following a CN injury improved EF preservation in this model, supporting the cavernosal oxygenation concept as protective mechanism for EF. The effects appear to be mediated via preservation of neurotrophic and endothelial factor expression. Müller A, Tal R, Donohue JF, Akin-Olugbade Y, Kobylarz K, Paduch D, Cutter SC, Mehrara BJ, Scardino PT, and Mulhall JP. The effect of hyperbaric oxygen therapy on erectile function recovery in a rat cavernous nerve injury model. J Sex Med 2008;5:562,570. [source]


Pharmacological and Functional Characterization of Novel EP and DP Receptor Agonists: DP1 Receptor Mediates Penile Erection in Multiple Species

THE JOURNAL OF SEXUAL MEDICINE, Issue 2 2008
Nadia Brugger PhD
ABSTRACT Introduction., Despite the widespread use of prostaglandin E1 as an efficacious treatment for male erectile dysfunction for more than two decades, research on prostanoid function in penile physiology has been limited. Aim., To characterize the pharmacological and physiological activity of novel subtype-selective EP and DP receptor agonists. Methods., Radioligand binding and second messenger assays were used to define receptor subtype specificity of the EP and DP agonists. Functional activity was further characterized using isolated human and rabbit penile cavernosal tissue in organ baths. In vivo activity was assessed in rabbits and rats by measuring changes in cavernous pressure after intracavernosal injection of receptor agonists. Main Outcome Measures., Receptor binding and signal transduction, smooth muscle contractile activity, erectile function. Results., In organ bath preparations of human cavernosal tissue contracted with phenylephrine, EP2- and EP4-selective agonists exhibited variable potency in causing relaxation. One of the compounds caused mild contraction, and none of the compounds was as effective as PGE1 (EC50 = 0.23 µM). There was no consistent correlation between the pharmacological profile (receptor binding and second messenger assays) of the EP agonists and their effect on cavernosal tissue tone. In contrast, the DP1-selective agonist AS702224 (EC50 =29 nM) was more effective in relaxing human cavernosal tissue than either PGE1, PGD2 (EC50 = 58 nM), or the DP agonist BW245C (EC50 =59 nM). In rabbit cavernosal tissue, PGE1 and PGD2 caused only contraction, while AS702224 and BW245C caused relaxation. Intracavernosal administration of AS702224 and BW245C also caused penile tumescence in rabbits and rats. For each compound, the erectile response improved with increasing dose and was significantly higher than vehicle alone. Conclusions., These data suggest that AS702224 is a potent DP1-selective agonist that causes penile erection. The DP1 receptor mediates relaxation in human cavernosal tissue, and stimulates pro-erectile responses in rat and rabbit. Thus, rabbits and rats can be useful models for investigating the physiological function of DP1 receptors. Brugger N, Kim NN, Araldi GL, Traish AM, and Palmer SS. Pharmacological and functional characterization of novel EP and DP receptor agonists: DP1 receptor mediates penile erection in multiple species. J Sex Med 2008;5:344,356. [source]


Effect of chronic renal failure on the purinergic responses of corpus cavernosal smooth muscle in rabbits

BJU INTERNATIONAL, Issue 6 2002
H. Kilicarslan
Objective ,To examine purinergic relaxation responses in chronic renal failure (CRF) in an experimental rabbit model, and thus evaluate the possible involvement of the purinergic system in erectile dysfunction with CRF. Materials and methods ,The relaxant effects of ATP were measured in strips of corpus cavernosum smooth muscle taken from control and CRF rabbits. CRF was induced in New Zealand white rabbits as previously described. Penises were excised from CRF rabbits 4 weeks after inducing uraemia. In an organ bath the strips from controls and CRF rabbit corpus cavernosum were pre-contracted with phenylephrine and increasing doses of adenosine and ATP added. Results ,In the pre-contracted rabbit cavernosal tissue the relaxations induced by adenosine and ATP were unchanged in CRF. Conclusion ,The lack of any relaxant effect of adenosine or ATP on the relaxation of cavernosal smooth muscle in rabbits with CRF might be because the relaxant effects of these agents are endothelium-independent and the endothelial purinergic receptor density was unchanged in CRF. [source]