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Inguinoscrotal testicular descent has been proposed to occur via sensory fibers of the sexually dimorphic genitofemoral nerve, which release a neurotransmitter, calcitonin gene related peptide, to guide the migrating gubernaculum into the scrotum. We hypothesize that androgen mediated regression of the genitofemoral nerve mammary branch is necessary for inguinoscrotal descent in rats. We compared the spatiotemporal development of the genitofemoral nerve in control and antiandrogen treated rats.A total of 29 Sprague-Dawley® rats were collected (animal ethics committee approval A644) in control and antiandrogen treated groups (flutamide, embryonic days 16 to 19, 75 mg/kg body weight/5% ethanol + oil) on embryonic days 17 and 19, and on postnatal day 2. Sagittal sections of the gubernaculum and its surrounding structures were processed for standard histology and immunohistochemistry for androgen receptor, nerves (Tuj1), calcitonin gene related peptide (marker for genitofemoral nerve) and cell nuclei (DAPI).The inguinal mammary bud, its adjacent androgen receptor and genitofemoral nerve mammary branch (containing calcitonin gene related peptide) persisted from embryonic day 17 to postnatal day 2 in all antiandrogen treated males, yet regressed in all control males by postnatal day 2.Antiandrogens resulted in the persistence of the mammary branch and inguinal mammary bud. Persistent genitofemoral nerve mammary branches may arrest or slow down gubernacular migration by releasing calcitonin gene related peptide in the mammary inguinal fat pad, thus reducing the chemotactic gradient to calcitonin gene related peptide from genitofemoral nerve branches in the distal scrotum. We hypothesize that this process may be related to antiandrogen induced cryptorchidism in the rodent.

Cryptorchidism is a common abnormality and normal testicular descent is controlled by the gubernaculum. The cremaster may originate from abdominal muscles during gubernacular eversion or alternatively it may develop inside the gubernaculum. We studied cremaster myogenesis to determine how it develops.Coronal sections of the pelvis were prepared from male Sprague-Dawley® rats and from males treated prenatally with the antiandrogen flutamide at embryonic day 19, and postnatal days 10, 19 and 35 after receiving ethical approval. Immunohistochemical stains were prepared for Ki67, Pax-7, myogenin, myosin heavy chain 7, Myh1, Myh2, Myh4, embryonic myosin, and slow and cardiac troponin T. Cell counts of the 1) gubernacular tip, 2) proximal gubernaculum/cremaster muscle and 3) adjacent abdominal wall are shown as a percent of positive fibers or positive cells per area.Throughout embryonic day 19, and postnatal days 10 and 19 proliferation (Ki67) was maximal at the gubernacular tip (p0.001), as were muscle stem cells markers (Pax-7 p0.05), early myogenesis (myogenin p0.001) and immature muscle (Myh7, and slow and cardiac troponin T p0.0001). In contrast, secondary (fast twitch, Myh1, 2 and 4) fibers were more common in abdominal muscles (p0.0001). Differences in muscle maturity and composition decreased with time. Flutamide treated rats showed more cellular proliferation than controls postnatally on postnatal day 10 (p0.001) as well as persistent immature embryonic myosin at the tip from postnatal day 19 (p0.05).Results show that the rat cremaster muscle is more immature at the gubernacular tip, consistent with myogenesis occurring in the gubernaculum during migration to the scrotum, as proposed in humans.

We evaluated long-term outcomes in boys treated for hypospadias at Royal Children's Hospital, Melbourne.Boys who underwent hypospadias surgery were reviewed at ages 13 to 15 years. Surgical results were evaluated using the Hypospadias Objective Scoring Evaluation. Lower urinary tract function was assessed using uroflowmetry and symptom questionnaire. Self-report surveys measured quality of life, patient satisfaction, memory of surgery, psychosexual outcomes and parent satisfaction with care.By Hypospadias Objective Scoring Evaluation score 80% of patients had an excellent surgical outcome. Two independent reviewers assessed lower urinary tract function as normal in 82% and 86% of cases, respectively. Quality of life scores were comparable to published values in normal children. Parents rated the institution highly. Overall 90% and 81% of boys were satisfied with the body and genital appearance, respectively. Those dissatisfied with genital appearance had poorer psychosexual outcomes than satisfied patients. When surgery was completed before age 5 years, boys had no perioperative memories. An association was found between no recollection of surgery and satisfaction with body appearance.Objective surgical and functional outcomes are excellent after early surgery. Post-repair quality of life is comparable to published data on normal children. Parents are pleased with care. Most boys are satisfied with the body and genital appearance. However, those dissatisfied with genital appearance must be identified in the interest of psychosexual development. The association between no recollection of treatment and satisfaction with body appearance suggests that surgery should be completed before age 5 years when possible to allow the development of good body image in adolescence.