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Mechanisms for the α-adrenoceptor-mediated positive inotropy in neonatal mouse ventricular myocardium were studied with isolated myocardial preparations. The phenylephrine-induced positive inotropy was suppressed by prazosin, nifedipine, and chelerythrine, a protein kinase C inhibitor, but not by SEA0400, a selective Na + /Ca 2+ exchanger inhibitor. Phenylephrine increased the L-type Ca 2+ channel current and prolonged the action potential duration, while the voltage-dependent K + channel current was not influenced. In the presence of cromakalim, an ATP-sensitive K + channel opener, the phenylephrine-induced prolongation of action potential duration, as well as the positive inotropy, were smaller than in the absence of cromakalim. These results suggest that the α-adrenoceptor-mediated positive inotropy is mediated by an increase in Ca 2+ influx through the L-type Ca 2+ channel, and the concomitant increase in action potential duration acts as an enhancing factor.

Background and Aims: Testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI) is an effective procedure for the treatment of male infertility, obstructive and non-obstructive azoospermia. We have reviewed our experience to investigate the correlation of TESE-ICSI with morphological, biophysical and endocrine profiles in 27 men. Results:  Testicular spermatozoa could be retrieved in 25 of 27 patients who underwent TESE. In two cases, testicular spermatozoa could not be recovered and their serum follicle-stimulating hormone (FSH) levels were significantly higher than those of the former group. However, spermatozoa could be retrieved in sufficient numbers for ICSI, even in the patient with the highest FSH concentration. Johnsen scores evaluated by diagnostic pre-TESE open biopsies were significantly higher in the cases with viable testicular spermatozoa than those in the cases without spermatozoa. However, even in the patient whose Johnsen score was 2.1, testicular spermatozoa could be retrieved with TESE, and pregnancy was achieved by ICSI. Conclusions:  The serum FSH levels and the histological findings of the testes were strong predictors for successful TESE and provided useful information for consultation and making treatment decisions on an individual case. However, whether a patient has enough spermatozoa so that an IVF procedure with ICSI is possible can only be answered by a trial TESE. (Reprod Med Biol 2003; 2 : 31-35).

A case of Sertoli cell tumor of the testicle is reported. A 33-year-old man visited the Chiba University Hospital with the chief complaint of a painless right testicular swelling on May 1990. The right testis was hard and swollen on palpation. Gynecomastia was not present. Serum levels of tumor markers and hormones including alphafetoprotein, human chorionic gonadotropin-beta, carcinoembryonic antigen, testosterone, prolactin, estradiol, luteinizing hormone, and follicle stimulating hormone were within normal limits. Ultrasonic examination showed a high echoic lesion in the right testis. Computerized tomography and magnetic resonance imaging showed no evidence of retroperitoneal lymph node enlargement. A high right orchiectomy was performed under a diagnosis of right testicular tumor. The right testis was elastic hard and measured 9 x 10 x 7 cm, weighing 450 g. The cut surface was light yellowish white and was completely displaced by the tumor. No normal tissue was seen. Histological examination showed a Sertoli cell tumor. No adjuvant therapy was performed. Neither recurrence nor evidence of metastasis has been detected for 8 years postoperatively.

Background: Although several studies indicate that larger varicoceles are associated with greater impairment of spermatogenesis, others suggest that the response to surgery is independent of varicocele size. In order to elucidate these seeming contradictions, correlations between the preoperative evaluation of varicoceles and improvement in semen quality after varicocelectomy were investigated., Methods: Forty men with left unilateral varicocele, followed for at least 6 months after varicocelectomy, were included in this study. The relationships between the grade of varicocele by palpation, Doppler examination, ultrasound, or scintigraphy were correlated with a postoperative improvement in sperm density or sperm motility., Results: Greater improvement in sperm density was observed in the patients with a large varicocele graded by palpation or measured by ultrasound, and greater improvement in sperm motility was observed in the patients with high uptake of radioactivity in the left side by scrotal scintigraphy., Conclusion: An improvement in semen quality after varicocelectomy is greater in patients with a large varicocele than in the patients with a small one. The significance of surgical repair of a small varicocele should be reconsidered.

Semen quality and endocrine parameters after spermatic cord torsion were investigated. Of 24 patients evaluated following spermatic cord torsion 12 were treated with bilateral orchiopexy (orchiopexy group), and 12 were treated with ipsilateral orchiectomy and contralateral orchiopexy (orchiectomy group). The average sperm density and the average total sperm count in the orchiectomy group were significantly lower than those in the orchiopexy group (p < 0.05, p < 0.05, respectively). The mean serum follicle stimulating hormone level in the orchiectomy group was significantly higher than that in the orchiopexy group (p < 0.05). These findings suggest a significant decrease in testicular function in the orchiectomy group. All the patients in the orchiopexy group demonstrated a normal semen quality and endocrine parameters during followup. Four of the 8 patients in the orchiectomy group whose duration of followup was more than two years still demonstrated oligozoospermia (< 20 x 10(6)/ml, one of 4 was azoospermia). The average age at operation of these four patients with abnormal semen quality was significantly higher than that of the other 4 patients with normal semen quality (p < 0.05), whereas no significant difference in duration of torsion preceding surgical therapy was observed between these two groups. These findings suggest that subsequent semen quality is likely to remain within normal limits with early surgical treatment by bilateral orchiopexy. Ipsilateral orchiectomy in the younger generation seems to result in less damage of the contralateral testis than in the older generation.

A 66-year-old female was admitted to Chiba University Hospital for the evaluation of a left adrenal mass which was incidentally discovered by computerized tomography. The patient had no clinical signs of Cushing's syndrome. Although the plasma ACTH level was suppressed, serum cortisol and urinary 17-OHCS levels were normal. Serum cortisol was not suppressed by dexamethasone and loss of diurnal rhythm of cortisol was observed. Uptake of 131I-aldosterone in the left adrenal gland was noted, but no accumulation was observed in the right one. Left adrenalectomy was performed. The tumor resected was 20 x 22 x 26 mm in size. Pathological diagnosis was adreno-cortical adenoma. Whether slight abnormality of adrenocortical function without clinical symptoms observed in the present case would develop into a clinically typical Cushing's syndrome remains to be solved.

Nineteen cases of sexual disturbance caused by endocrine dysfunction were surveyed for the clinical features. In hypogonadotropic hypogonadism ejaculatory failure was observed in 12 out of 13 cases. On the contrary, 2 of three hypergonadotropic patients preserved their ejaculation. The serum testosterone levels of hypogonadotropic and hypergonadotropic hypogonadism were less than 200 ng/dl. When the testosterone level decreased to less than 100 ng/dl, nine patients out of 13 complained loss of libido and 12 patients complained loss of ejaculation, but six patients preserved erectile function. Hyperprolactinemic patients showed loss of libido in 4, erectile failure in 4 and loss of ejaculation in 2. When good response to hCG test was present or the testicular volume was more than 4 ml, patients with hypogonadotropic hypogonadism showed good response to hCG therapy.

The testicular function after orchiopexy for unilateral cryptorchism was examined for fertile state with the relation to the age at operation and the testicular size. Sperm concentration decreased with the age at operation, accompanying a rise of gonadotropins and a decrease of the testicular size. The testicular size decreased with the age at operation. sperm deterioration was correlated more with the testicular size in the normally descending side than that of the operated one. The gonadotropin level was inversely correlated with the size of the contralateral normally descending testis. These results indicate that fertility after unilateral orchiopexy is influenced by the age at operation as well as the development of the normally descending contralateral testis.

A 33-year-old male presented to the Chiba University Hospital with the main complaint of right flank pain. Bilateral vas deferens were not palpable. Hormonal examination revealed hypergonadotropic hypogonadism and cytogenetic studies a 47,XXY karyotype. The significance of the association of this karyotype with the absence of vas deferens is discussed.

13 patients with bladder diverticula underwent transurethral diverticulectomy. Follow-up cystograms were obtained six months after surgery. The diverticulum had shrunk in all cases and had totally disappeared in 11 (85%). Transurethral diverticulectomy is a simple, effective, and safe procedure. It takes only a short time and can easily be combined with transurethral operations for obstructions of the lower urinary tract.