Bulk collection of epididymal tail spermatozoa by means of electric stimulation

Research Project

Project/Area Number	04670973
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Urology
Research Institution	Yokohama City University
Principal Investigator	KINOSHITA Yuzo Yokohama City University, School of Medicine, Associate Professor, 医学部, 助教授 (00186298)
Co-Investigator(Kenkyū-buntansha)	HOSAKA Masahiko Yokohama City University, School of Medicine, Professor, 医学部, 教授 (30106330)
Project Period (FY)	1992 – 1994
Project Status	Completed (Fiscal Year 1994)
Budget Amount *help	¥2,100,000 (Direct Cost: ¥2,100,000) Fiscal Year 1994: ¥400,000 (Direct Cost: ¥400,000) Fiscal Year 1993: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1992: ¥1,200,000 (Direct Cost: ¥1,200,000)
Keywords	Epididymis / Electric stimulation / Spermatozoa / 精子運動 / 電位負荷 / 副睾丸
Research Abstract	In 12-week-old Wistar rats, 70V,250 mu s pulse width, 20 Hz electric stimulation on the epididymal tail for 30 s resulted in a recovery of 10.5(]SY.+-。[)2.2 mu l of epididymal fluid containing 46 ((]SY.+-。[)14) x 10<@D16@>D1 spermatozoa. Simple dispersion of the collected epididymal fluid into F12 yielded pure suspensions of motile sperms. In the electric stimulation, spermatozoa may underwent loss of motility in two different mechanisms. In the condition of low ionic strength, 50% of motile spermatozoa lose motility in the high electric gradient about 160V/2mm. In the high ionic strength, spermatozoa lose motility even in low electric gradient but this takes places only near electrode. In men with obstructive diseases of the vas deferens, the epididymal spermatozoa could be collected by means of electric stimulation but not so consistently as in the animal experiments. The highest successful rate was observed in the cases where the obstruction is of the functional origin such as post-lymphadenectomy of the paraortic nodes.