ABSTRACT:We examined changes in the serum testosterone level and in sperm in the testis and epididymis by using tail-suspended mice, which are a simulation model of the body fluid shift in space, to evaluate the possibility of spermatogenesis failure in space environment. We also studied pathological disorders of the testis in the tailsuspended mice. Tail suspension was imposed with a tail harness to a degree at which the hindlegs of mice did not touch the floor of the housing unit. In control mice, the tail was similarly fixed with a tail harness to impose the same stress, except that a hindleg remained on the floor. Body weight was not significantly different between the 2 groups during 7 days, and testicular weight was significantly different. The testosterone level was significantly lower in the tail-suspended group (0.71 Ϯ 1.24 ng/mL) than in the control group (2.38 Ϯ 3.50 ng/mL; P Ͻ .05). Microscopy with hematoxylin and eosin (HE) and periodic acid-Schiff (PAS) staining showed a small proportion of seminiferous tubules with impairment of spermatogenic function in the tailsuspended group, and multinucleated giant cells were occasionally noted. Terminal deoxynucleotidyl tranferase-mediated nick end-labeling staining revealed positive cells even in animals in which impairment was considered to be mild based on HE and PAS staining. Many cells showed intense p53 immunostaining compared to the control group, with more intense staining of the nucleus in the tail-suspended group. The proportion of motile sperm was slightly but not significantly reduced in the tail-suspended group. However, the mean movement velocity of the motile spermatozoa was significantly decreased.

Nested variants of transitional cell carcinomas (TCC-NVs) are relatively rare neoplasms in the urinary bladder, but at least 25 cases have been described. This disease is characterized by the pathological finding of irregular nests and/or tubules of transitional carcinoma cells infiltrating the lamina propria without involvement of the mucosal layer. In our case, diagnosed by open biopsy, there were scattered tumor cells observed from the muscle layer to the subserosa, with a tendency toward increasing cellular anaplasia with the depth of invasion. Since the prognosis of TCC-NV is generally poor, comprehensive chemotherapy was performed. No changes were observed on computed tomography and the performance status (0) remained the same after 1 year, so the treatment was considered effective. We conclude that open biopsy should be carried out without hesitation when bladder cancer is suspected, even if there are negative findings of repeated urinary cytology examination and/or endoscopic cold cup biopsy. Immunohistochemical analysis may help in the diagnosis of TCC-NVs derived from epithelial cells. Diagnosis and treatment at an early stage should reduce the mortality of patients with TCC-NVs.

Pheromone receptors are expressed in the accessory olfactory system, which is vital for non-specific chemical communication and for sexual behavior. Under the hypothesis that some of the pheromone molecules released from female reproductive organs might regulate sperm chemotaxis or chemokinesis, we examined whether the V1R type pheromone receptor mRNAs are expressed in developing germ cells. By a reverse transcription-PCR method, we obtained nine kinds of cDNA fragments belonging to the receptor family. In situ hybridization analysis in testicular sections using probes of testicular pheromone receptors (TVRs) revealed that TVR mRNAs were expressed by spermatids. TVRs were also expressed in the accessory olfactory organ. In the testis, hybridization signals were localized in subsets of the seminiferous tubules, suggesting that TVRs were expressed by selective subsets of the spermatids. In situ hybridization study suggests also that each sperm expresses multiple pheromone receptors. The testicular pheromone receptors might have an important role in the maturation and/or migration of sperm. ß

It is known that testosterone deficiency induces apoptosis in the prostate and that p53 protein is involved in this apoptosis. Therefore, p53 protein may also be involved in apoptosis induction in a testosterone-deficient state in the penis. In this study, we investigated whether castration and chemical castration induce apoptosis at penile tissue in rats, and whether p53 protein is involved in this apoptosis. Male SD rats aged 8 weeks were divided into four groups: 1) the Control group; 2) the Castration group; 3) the Estrogen group, in which rats received betaestradiol 17-(beta-D-glucuronide) injection of 500 microg/body/day; and 4) the LH-RH group, in which rats received LH-RH analogue (leuprorelin acetate) injection of 2 mg/kg. The rats were sacrificed after treatment on days 1, 3, 5, 14, and 28 by cervical dislocation. Apoptotic cells and p53 protein-positive cells were observed on the 5th day after treatment and thereafter in all castration, estrogen, and LH-RH groups. These findings showed that both castration and chemical castration induced p53 protein in vascular endothelial cells in the corpus cavernosus during the process of losing testosterone. It was also suggested that in such states, apoptosis is induced in vascular endotherial cells in the corpus cavernosus.