Various Isoforms of Myomodulin Identified from the Male Copulatory Organ of Lymnaea Show Overlapping yet Distinct Modulatory Effects on the Penis Muscle

Abstract: Male copulatory behavior in the snail Lymnaea stagnalis is controlled by several types of peptidergic neurons, including a cluster of neurons in the ventral lobe of the right cerebral ganglion that show immunoreactivity to myomodulin-A of Aplysia and innervate the penis complex. We identified structurally myomodulin-A and three related peptides from Lymnaea and showed that they are present in a characteristic ratio in both the penis nerve and penis complex, suggesting that they are processed from a single precursor and transported from the ventral lobe to the penis complex. All four peptides decreased the relaxation time of electrically evoked contractions of the penis retractor muscle. However, their effects on the amplitude of contraction were different, ranging from no effect to an increase or a decrease in the amplitude. A mixture of the peptides in a ratio as determined by direct mass spectrometry of the penis nerve decreased the contraction time, the relaxation time, and the amplitude. These effects resemble those of one particular peptide in the mixture. The direct mass spectrometry determinations of the peptide profile in the penis nerve suggest that many more, as yet unidentified, neuropeptides are involved in modulation of muscle activities of the penis complex.     

Right-handed penises of the earwig Labidura riparia (Insecta, Dermaptera, Labiduridae): evolutionary relationships between structural and behavioral asymmetries

The number of penises vary in the insect suborder Forficulina (order Dermaptera; earwigs). Males of the families Diplatyidae, Pigidicranidae, Anisolabididae, Apachyidae, and Labiduridae have two penises (right and left), while those of the Spongipohridae, Chelisochidae, and Forficulidae have a single penis. The proposed phylogenetic relationships among these families suggest that the single‐penis families evolved from an ancestor possessing two penises. To date, examinations of double‐penis earwig species have found that only a single penis is used per single copulation. These diversities in structural and behavioral aspects of genitalia raises the following intriguing questions: How are the two penises used? Why did a penis degenerate in several earwig families, and which one was lost? To address these questions, structural and behavioral asymmetries were examined in detail for a representative species Labidura riparia (Labiduridae). Although there was no detectable morphological differentiation between the right and left penises, male L. riparia predominantly used the right one for insemination. This significant “right‐handedness” developed without any experience of mating and was also manifested in the resting postures of the two penises when not engaged in copulation. However, surgical ablation of the right penis did not influence the insemination capacity of males. In wild‐caught males, only about 10% were left‐handed; within this group, abnormalities were frequently observed in the right penis. These lines of evidence indicate that the left penis is merely a spare intromittent organ, which most L. riparia males are likely never to use. Additional observations of five species of single‐penis families revealed that the left penis degenerated in the common ancestor of this group. Considering the proposed sister relationship between the Labiduridae and the single‐penis families, it is possible that such behavioral asymmetries in penis' use, as observed in L. riparia, are parental to the evolutionary degeneration of the infrequently used left penis. J. Morphol., 2006. © 2006 Wiley‐Liss, Inc.     

Diphallia in a mixed-breed dog with multiple anomalies

Complete diphallia was detected in a six-month-old Poodle cross dog. Duplication of the urinary bladder, right renal hypoplasia, bifurcation of the descending colon and bilateral cryptorchidism were also present. The left urethra was patent, and emptied the left urinary bladder; the right urethra ended blindly at a point 2.5 cm from the tip of the right penis. The left urinary bladder was joined medially to a right urinary bladder with no interbladder communication; however, the right bladder opened caudally into a blind sac which drained into the left prostatic urethra. Pyelonephritis of the left kidney was present, and was suspected to be due to ascending bacterial infection of the right urinary bladder and the right segment of the bifurcated descending colon, which terminated at the apex of the right urinary bladder. Diphallia and associated urogenital anomalies are reviewed.     

Fitness advantages of the biased use of paired laterally symmetrical penises in an insect

The evolution of laterality, that is the biased use of laterally paired, morphologically symmetrical organs, has attracted the interest of researchers from a variety of disciplines. It is, however, difficult to quantify the fitness benefits of laterality because many organs, such as human hands, possess multimodal functions. Males of the earwig Labidura riparia (Insecta: Dermaptera: Labiduridae) have morphologically similar laterally paired penises, only one of which is used for inseminating the female during a single copulation bout, and thus provide a rare opportunity to address how selection pressure may shape the evolution of population‐level laterality. Our population studies revealed that in 10 populations, located at 2.23–43.3° north, the right penis is predominantly used for copulating (88.6%). A damaged penis was found in 23% of rare left‐handers, suggesting that the left penis can function as a spare when the right one is damaged. By pairing L. riparia females with surgically manipulated males, we found that males forced to use the right penis outperformed left‐handed males in copulation (the probability of establishing genital coupling during the 1‐hr observation period: odds ratio [OR] of 3.50) and insemination (probability of transferring a detectable amount of sperm: OR of 2.94). This right‐handed advantage may be due to the coiled morphology of the sperm storage organ with a right‐facing opening. Thus, female genital morphology may play a significant role in the evolution of handedness and may have acted as a driving force to reduce penis number in related taxa.     

Modified penis lengthening surgery: review of 52 cases

A modified surgical method for penis lengthening was, for the first time, set up in this laboratory. The procedure involves covering the dissected corpus cavernosum with either a scrotal flap or a skin graft after releasing the superficial ligament and even some deep suspensory ligament. The advantage of the scrotal flap is emphasized to cover the wound, and a V-Y suture was made to avoid the traction. The results, both in appearance and increased length, were satisfactory in 52 cases. Among the 52 patients, 39 suffered from congenital short penis and 13 from traumatic injuries. The significance and the blood supply of the penis are discussed.     

Peptidergic modulation of male sexual behavior in Lymnaea stagnalis: structural and functional characterization of -FVamide neuropeptides

In the simultaneous hermaphrodite snail Lymnaea stagnalis, copulation as a male is controlled by neurons that send axons to the male copulatory organs via a single penis nerve. Using direct mass spectrometry of a penis nerve sample, we show that one of the molecular ions has a mass corresponding to GAPRFVamide, previously identified from the buccal ganglia, and named Lymnaea inhibitory peptide (LIP). The identity of this peptide is confirmed by partial peptide purification from the penis nerve, followed by post source decay mass spectrometry. We cloned the LIP-encoding cDNA, which predicts a prohormone that gives rise to five copies of LIP (now re-named LIP A), two other -FVamide peptides (LIPs B and C), and five structurally unrelated peptides. The LIP gene is expressed in neurons of the right cerebral ventral lobe that send their axons into the penis nerve. We show that the LIP A peptide is present in these neurons and in the penis nerve, and confirmed the presence of LIP B and C in the penis nerve by post source decay mass spectrometry. Finally, we demonstrate that LIP A, B and C inhibit the contractions of the penis retractor muscle, thereby implicating their role in male copulation behavior.     

Brain cells that command sexual behavior in the snail Helix aspersa

Evidence is presented indicating that the mesocerebrum of the terrestrial snail, Helix aspersa, has a major role in the control of sexual behavior. Morphological and physiological results demonstrate a right-sided bias in the mesocerebrum that is consistent with the fact that sexual behavior is executed almost entirely on the animal's right side. Thus, the right lobe has 23% more neurons than the left lobe, and they are 24% larger. Excitatory synaptic inputs derive predominately from neurons on the right side. The axons of right-side mesocerebral neurons go to the right pedal ganglion almost without exception, and even the axons of left-side neurons travel mostly in right-side connective nerves. Direct evidence for a role of the mesocerebrum in commanding sexual behavior comes from experiments with electrical stimulation. Extracellular stimulation of the right mesocerebrum, but not the left mesocerebrum, resulted in movements of the "love dart" sac and the penis. Intracellular stimulation of neurons in the right mesocerebrum evoked measurable movements of either the dart sac or the penis, or both, in 17% of the cells tested. The latencies ranged between 5 and 50 s. In an intact animal, these movements would cause a release of the dart and an eversion of the penis. The motor effects were mediated through the right cerebropedal connective and the pedal nerve NCPD, with the motorneurons probably situated in the right pedal ganglion.     

A propos de 10 cas de cancer du penis: Revue de la litterature

The epidermoid cancer of the male penis is a little frequent tumor. At early stage, the treatment is conservative (curi therapy and laser therapy). At advanced stage the treatment of the primary lesions is amputation. Prognosis depends on the presence or absence of lymph nodes metastasis. The management of lymph nodes metastatis is still controversial. Radical lymph nodes excision is the only effective treatment, but associated with high morbidity. The detection of papilloma gene virus in the tumor incites to search for such virus lesions by peniscopy and to treat them.     

Strangulation de la verge par anneau métallique compliquée d’une lésion urétrale

Penile incarceration is uncommon. The diagnosis is obvious, but extraction of the constrictive ring and repair of the damage can be challenging. The authors present the case of a 61-year-old man wh presented with pain and swelling of the penis 3 weeks after applying a metal ring (double key rings) at the base of penis for the purposes of self-mutilation. The key ring was removed immediately under local anaesthesia. One week later, a urethral fistula was observed, requiring suprapubic cystostomy. It was decided to perform secondary surgical closure of the fistula and reconstruction of the skin of the base of the penis after treatment of local sepsis. Penile incarceration should be considered to be an emergency, as the more rapidly the constrictive object is removed, the lower the risk of complications secondary to penile devascularization, urinary retention and urethral damage. The authors review the literature concerning this unusual injury and its management.     

Pulsed electromagnetic fields accelerate wound healing in the skin of diabetic rats

Delayed wound healing is a common complication in diabetes mellitus. From this point of view, the main purpose of the present study is to investigate the effect of extremely low frequency pulsed electromagnetic fields (ELF PEMFs) on skin wound healing in diabetic rats. In this study, diabetes was induced in male Wistar rats via a single subcutaneous injection of 65 mg/kg streptozocin (freshly dissolved in sterile saline, 0.9%). One month after the induction of diabetes, a full‐thickness dermal incision (35 mm length) was made on the right side of the paravertebral region. The wound was exposed to ELF PEMF (20 Hz, 4 ms, 8 mT) for 1 h per day. Wound healing was evaluated by measuring surface area, percentage of healing, duration of healing, and wound tensile strength. Obtained results showed that the duration of wound healing in diabetic rats in comparison with the control group was significantly increased. In contrast, the rate of healing in diabetic rats receiving PEMF was significantly greater than in the diabetic control group. The wound tensile strength also was significantly greater than the control animals. In addition, the duration of wound healing in the control group receiving PEMF was less than the sham group. Based on the above‐mentioned results we concluded that this study provides some evidence to support the use of ELF PEMFs to accelerate diabetic wound healing. Further research is needed to determine the PEMF mechanisms in acceleration of wound healing in diabetic rats. Bioelectromagnetics 31:318–323, 2010. © 2010 Wiley‐Liss, Inc.     

Traitement médical de la maladie De La Peyronie

Peyronie’s disease is characterized by the presence of a scar, called a plaque, involving the tunica albuginea of the corpora carvernosa. This may be associated early in its course with painful erections and subsequently with deformity of the erect penis. During the acute phase, multiple conservative treatments have been aimed at control of clinical symptoms. Comparative studies between these therapies show no difference in terms of results. In addition, no controlled study has been able to point out that the patients receiving these treatments do better than those receiving no treatment. We usually give vitamin E because this oral therapy is easy to use and have no side effects. Persistence of pain is, to our minds, the only indication for radiation therapy. A small dose of radiation delivered by a soft modality can allay residual pain. New conservative treatments of Peyronie’s disease have been reported. Orgotein injections give the most encouraging results, especially when associated with transdermal electromotive administration. To confirme these results we require prospective double-blind studies.     

Hétéromutilation pénienne: à propos d’un cas à la clinique universitaire d’urologie-andrologie du centre national hospitalier universitaire Hubert-Koutoukou-Maga (CNHU HKM) de Cotonou (Bénin)

Amputations of the penis are rare injuries, most often found in self-mutilation where patients have psychiatric problem.We report a case of traumatic amputation of the penis by physical aggression received at the University Teaching Hospital Clinic of Urology-Andrology CNHU HKM Cotonou. The section of the penis is located 3 cm from the base. The amputated segment is not found. The management of the patient was double. Initially, it was urgently performed surgery to stop bleeding, stabilize the stump and pose of a urinary catheter and a psychiatric treatment at a later time. The evolution is favorable, with good healing of the stump and an improvement in psychiatric condition as antidepressant. Methods of reconstructive surgery such transplants could be considered.     

Ultrasound-guided injection of contrast medium into the crus penis for diagnosis of erection failure in bulls

The objectives of this study were to demonstrate the ability to cannulate the crurae of the bull's penis under ultrasound guidance, to demonstrate contrast medium injected by this route in the distal penis, and to confirm the technique to be safe and repeatable. Five adult bulls with normal serving ability were used, one being subjected to the procedure twice. The procedure was performed with the bulls under general anesthesia and in lateral recumbency. A spinal needle was passed through the skin and into the crus penis under ultrasound guidance and two syringes containing an iodine-based contrast medium were connected to it. Stimulation using an electro-ejaculator with a rectal probe was initiated, and when the penis started developing an erection, 50-100 ml of contrast medium was injected. Lateral and ventro-dorsal radiographs were taken of the extended penis during, and at intervals after, injection. After a rest period of 5 min, clearance of the contrast medium was confinned and the procedure was repeated on the other crus penis. Each case therefore, contained two attempts. Successful cannulation of the crus penis was confirmed by observing indentation of its fibrous wall by the needle, free flow of blood, lack of resistance to the injection of air, which could be seen in the crus, and fluctuation of resistance to injection in synchrony with the pulsation of the electroejaculator. Contrast medium was demonstrated in the mid or distal portion of the penis in all six cases, or on 9 of the 12 attempts. Attainment of penile erection, a larger volume of contrast medium, and the order of cannulation all enhanced flow of contrast medium to the distal portion of the penis, with the first crus giving better results. On one occasion the needle worked out of the crus penis during stimulation, resulting in injection of contrast medium into the corpus spongiosum penis. All bulls recovered uneventfully and returned to normal serving ability. It is concluded that ultrasound-guided cannulation of the crus penis is a safe and successful method for the injection of contrast medium for contrast studies of the penis, and is less invasive than the surgical method.     

The Distance to Which Wound Effects Influence the Structure of Secondary Xylem of Decapitated Pinus pinea

Decapitation of stems of annuals and trees for the study of vascular and fiber differentiation with or without hormonal application is a common procedure. There is controversy about whether wound effects play a role in such experiments, and to what distance from the point of decapitation. To examine this question, the distance from the point of decapitation at which apparent wound effects are obvious developmentally, was studied in decapitated 4-year-old Pinus pinea plants. The wound effects just below the cut included differentiation of many traumatic resin ducts, a parenchyma band instead of tracheids, more tracheid files, and a higher proportion of late wood. The increase in the number of resin ducts was still considerable and statistically significant 10 cm below the point of decapitation compared with the nondecapitated control. These results indicate that in pines, wound effects in the first 5 cm below the decapitation point (a common point for tissue examination) cannot be ignored in experiments on the regulation of vascular differentiation.     

Epiphallus anatomy in the Arion hortensis species aggregate (Mollusca, Pulmonata)

A SEM study of the structure associated with the outlet of the epiphallus in the atrium genitale of three arionid species ( Arion hortensis s.s., A. distinctus and A. owenii ) is presented. The structures are described and compared, and the specific differences are outlined. Preliminary notes on the same structure in A. intermedius , as well as on the spermatophores of A. hortensis s.s. and A. distinctus , are also provided. It is concluded that A. owenii stands somewhat apart in relation to the latter two species, since it may be more related to A. intermedius. Although it is generally accepted that the genus Arion is characterized by the absence of a penis, it is suggested here that the described structure at the outlet of the epiphallus is nothing but a remnant of an ancestral penis; anyhow, it is at least functionally allied to a penis.     

Fine structure of the male reproductive system in two species ofHaplognathia sterrer (Gnathostomulida,Filospermoidea)

Summary The structure of the male reproductive systems of two species ofHaplognathia cf.lyra andH. cf.rosacea was described. The structure of the testes and the anterior portions of the sperm ducts in both species was found to be similar. However, considerable species differences were found between the structures of the glands and muscles associated with the reproductive systems. These were more elaborate inH. cf.lyra than inH. cf.rosacea. The former species possessed an H-shaped sperm duct gland, three distinct groups of penis muscles and a penis with two cell types and with a lumen. The latter species had paired sperm duct glands, no specialized penis muscles and a penis with only one cell type and without a detectable lumen. No open gonopore was observed in either species. The sperm presumably exit through a ventral tissue connection observed connecting the penis and the ventral epidermis. These findings were discussed in the light of Mainitz's (1977) theory concerning the primitive penis type within the Gnathostomulida.Abbreviations ap anterior-posterior penis muscles - bm basement membrane - csd common sperm duct - dl dorsal lumen of the penis - dp dorsal gland cells of the penis - dv dorsoventral muscles anterior to the penis - dw sperm duct wall cell - e epidermis - ex exit cell - g intestine - gl gut lumen - n nerve - p penis - sd sperm duct - sdg sperm duct gland - tw testes wall cell - vl ventral lumen of the penis - vp ventral gland cells of the penis This project was supported by NSF grant #GB 42211 (R.M. Rieger P.I.). The line drawings have been executed after our design by Ms. Linda McVay     

Résultats hémodynamiques et cliniques de la dissection, assistée par lunettes chirurgicales, des veines spermatiques au niveau de l’orifice inguinal interne

Inversion of venous flow is well visualized by colour duplex ultrasound and is the basic haemodynamic feature of varicocele. We tried to assess the value of dissection of branches of the spermatic vein in the internal inguinal ring using an operating microscope with a magnification of 4.5x. 16 patients were operated according to the ultrasound classification proposed by Hirsh et al. [8]. Varicocele was grade III in 2 cases, grade IV in 11 cases and grade V in 3 cases and was situated on the left in 13 patients and on the right in 3 patients. The diagnosis was based on clinical examination and colour duplex ultrasound. The operating time was 25–35 min. The incision was 1.5 to 2 cm long. No short-term complications or long-term hydrocele were observed. No reno-spermatic flow was observed on colour duplex ultrasound after six months. The mean testicular volume was 22 ml before surgery and did not change after the operation. This surgical technique is less invasive than the conventional retroperitoneal or laparoscopic procedures, and the incision is smaller than with the percutaneous technique. It is less radical than conventional microsurgery, but the operating time is shorter, and the surgical wound is smaller, sparing the artery and lymphatic vessels. In conclusion, this operation can be considered to be a good option in the surgical treatment of varicocele in view of its low complication rate, the absence of hydrocele, a minimally invasive procedure and the good haemodynamic results.     

Basic morphological data of external genitals in 177 healthy Central European men

Five basic measurements were made of the penis, the scrotum and the testicles of 177 healthy Bohemian (Czechoslovakian) men, 18–20 years of age. The average length of the penis was 72.18 mm. The average circumference of the penis was 95.65 mm. The length of the right testicle was 47.37 mm, the length of the left was 45.17 mm. In 16.2% of those examined slight deformations of the urethral opening and mild malformations of the prepuce and the frenum were found. These defects did not disturb function. The method of measurement used has been described.     

Urogenital system of the spotted hyena (Crocuta crocuta Erxleben): a functional histological study

The unique urogenital anatomy and histology of female spotted hyenas (Crocuta crocuta Erxleben) was reexamined to identify adaptations of "structure" that enable/facilitate urination, mating, and parturition through the clitoris. Unusual features of penile anatomy required for meeting ceremonies and successful mating through a clitoral point of insertion were also examined. As reported previously, the upper urogenital tract of the female spotted hyena is typical of other carnivores and consists of the oviducts, uterine horns, uterine body, and vagina. An anatomically defined cervix is absent, even though a histologically defined transition zone between the uterine body and vagina was demonstrated. Adaptive features of the upper genital tract were a helical-shaped uterine cavity, extensive smooth muscle in the uterus and vagina, and a newly discovered submucosal mucous urogenital gland (SMUG) located immediately caudal to the vagina. The extensive smooth muscle facilitates the expulsion of the large pups at parturition through the recurved birth canal. Secretions of the SMUG provide lubrication and protection for the urogenital mucosa during mating and parturition. Two types of "erections" are suggested by behavioral observations: the common hemodynamic erection required for insertion and thrusting by the male, and phallic "flipping" that commonly occurs earlier in the mating sequence and is sometimes seen during meeting ceremonies. Phallic "flipping" appears to be accomplished by the coordinated contractions of the large ischiocavernosus and retractor muscles acting on the semirigid organ. The extremely thick tunica albuginea and interstitial collagen of the common corporal body of the penis and clitoris gives the flaccid phallus some degree of rigidity even in the resting state in males and nulliparous females. Phallic "flipping" implies a hinge region in which flexibility is the key feature. Such a proximal hinge region of the male and female phallus was defined and was notable for its diminished collagen content. The urogenital sinus traversing the clitoris was specialized for distensibility, thus facilitating receipt of the penis during mating and for passage of the infant to the tip of the glans clitoris, where it emerges at parturition. The morphology of the glans penis is notable for the tapered common corporal body that extends to the distal tip of the glans. This adaptation is suggested to be required for a clitoral (as opposed to a vaginal) point of insertion during mating. Finally, additional segments of erectile tissue devoid of a thick collagenous capsule were demonstrated in the glans penis and glans clitoris, which appear to account for the "partially-locking" of the male into the female during the late stages of a mating sequence. Taken together, it is evident that the unusual sexual behaviors of the male and female spotted hyenas are facilitated by unique structural modifications of the relevant organs.