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Kazunori Kimura

Publications and source records attributed to Kazunori Kimura.

4 recordsLinked to original sources
PubMed2004

The neuronal and endothelium-dependent relaxing responses of human corpus cavernosum under physiological oxygen tension last longer than previously expected.

BACKGROUND: Intracavernosal oxygen tension varies greatly in the process of erection. Blood extracted from the human penis demonstrates an increase from approximately 30 mmHg Po(2) in the flaccid state to 100 mmHg in the erect state of the penis. In the present study, using these levels as a guide, we investigate how the NO-dependent relaxation of human corpus cavernosum changed under physiological oxygen tensions ranging from approximately 30 to 100 mmHg. METHODS: Human penile tissue specimens were obtained at penile surgery with informed consent from the patients. The preparations were mounted in Krebs solution in an organ bath and the isometric tension was recorded. Krebs solutions of various oxygen tensions were prepared by bubbling 5% CO(2) in N(2) and O(2). The NO-dependent relaxation caused by electrical field stimulation (EFS) and acetylcholine (ACh) was studied, and the amplitude and duration of relaxation evaluated. RESULTS: The amplitude of relaxation induced by EFS was significantly decreased under physiological oxygen tension conditions (P < 0.01). The duration of the relaxant response induced by EFS and ACh was significantly prolonged in physiological oxygen tension conditions than in high oxygen tension (P < 0.01). However, there was no correlation between the duration of relaxation induced by EFS and each physiological oxygen tension level. The duration of relaxation induced by ACh was most prolonged at 60-69 mmHg oxygen tension. CONCLUSION: Physiologically, the effect of NO may last longer than was previously thought. In addition, it would seem that there is an optimal physiological oxygen tension for maximum ACh-induced relaxation.

Acetylcholine↗
PubMed2004

Penile revascularization surgery for arteriogenic erectile dysfunction: the long-term efficacy rate calculated by survival analysis.

OBJECTIVE: To determine the subjective and objective outcomes (by survival analysis) after penile revascularization surgery in patients with arteriogenic erectile dysfunction (ED), selected by established strict criteria. PATIENTS AND METHODS: The study included 51 patients diagnosed with arteriogenic ED caused by localised arterial lesions and who had microscopic penile revascularization surgery between January 1996 and March 2002. Before surgery, all patients had a full examination, including a medical and sexual history, laboratory testing, intracavernosal pharmacological tests, colour Doppler ultrasonography (CDU), pharmacodynamic infusion cavernosometry and cavernosography, and digital subtraction angiography (DSA). Penile revascularization surgery was indicated only in patients aged <50 years and with no history of diabetes mellitus, hypertension or hyperlipidaemia. When there were communicating branches between the dorsal and cavernosal arteries, Hauri's procedure was used; when there were none or there was no evidence for them on both CDU and DSA because of severe narrowing or obstruction in the proximal common penile artery, the Furlow-Fisher modification of the Virag V procedure (FFV5) was used. The patency of the neo-arterial blood flow was assessed by CDU and effective rates calculated using the Kaplan-Meier method. The efficacy rate was recalculated whenever there was a recurrence. When occlusion of the neo-arterial blood was confirmed by CDU the date of occlusion was set as that midway between the last examination showing patency of the donor vessel and the latest examination indicating the occlusion. The patency period was the number of days from surgery to the date of occlusion. RESULTS: Of the 51 patients, 26 had Hauri's and 23 the FFV5 procedure (median age 32 years, range 21-49); in two patients with a previous pelvic fracture surgery was not possible because of scar formation in the dorsal area at the base of the penis. The mean (sd) subjectively estimated efficacy rate was 85.9 (6.3)% after 3 and 67.5 (10.7)% after 5 years of follow-up. The duration at 75% efficacy was 41.0 (5.6) months. The objectively estimated efficacy rate was 84.9 (7.3)% at 3 and 65.5 (13.5)% after 5 years of follow-up. The duration at 75% patency was 42.4 (9.5) months, and at 50% was 60.6 (19.4) months. There was no significant difference in subjective outcome between the FFV5 and Hauri procedures (P = 0.38, log rank test) and none objective outcome after surgery (P = 0.19, log rank test). Thirteen of the 18 patients in the Hauri group had venous dilatation in the deep dorsal, obturator, prostatic and the internal iliac veins. There were operative complications in four patients (hyperaemia of the glans in two, and one each with haemorrhage from the anastomosis site and scar contracture). CONCLUSIONS: The long-term efficacy rates (by the Kaplan-Meier method) of the Hauri and FFV5 procedures were both acceptable. The selection criteria gave acceptable outcomes from both procedures. Penile revascularization surgery is a treatment suitable only for young men and therefore attention must be given not only to the long-term outcome but also to long-term adverse events.

Adult↗
PubMed2002

[Nitric oxide].

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Animals↗