Study of the mechanism of spermtransport and nerve control, and its clinical application
Grant-in-Aid for Scientific Research (B)
|Allocation Type||Single-year Grants|
|Research Institution||Tokyo Medical and Dental University|
OSHIMA Hiroyuki Tokyo Medical and Dental University Urology Professor, 医学部, 教授 (60013934)
KITAHARA Satoshi Tokyo Medical and Dental University Urology Assitant Professor, 医学部, 講師 (10186257)
SATO Kenji Tokyo Medical and Dental University Anatomy Professor, 医学部, 教授 (20107246)
KIHARA Kazunori Tokyo Medical and Dental University Urology Assistant Professor, 医学部, 講師 (40161541)
|Project Period (FY)
1994 – 1996
Completed(Fiscal Year 1996)
|Budget Amount *help
¥5,900,000 (Direct Cost : ¥5,900,000)
Fiscal Year 1996 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1995 : ¥1,700,000 (Direct Cost : ¥1,700,000)
Fiscal Year 1994 : ¥3,200,000 (Direct Cost : ¥3,200,000)
|Keywords||Vas deferens / Autonomic nerve / Sperm transport / 自律神経 / メカニズム|
I.Autonomic nervous system controlling sperm transport through the vas deferens.
In mammalians the nerve pathway from the lumbar splanchnic nerve (L_<2-5>) to the vas deferens via the hypogastric nerve controls sperm transport through the vas with double cross-innervation system. The two crossing points were the inferior mesenteric plexus (superior hypogastric plexus in human) and the commissural branches between bilateral pelvic plexuses. We found that stimulation of the pelvic nerve which does not elicit elevation of vasal pressure in intact animals is able to elicit elevation of vasal pressure after transection of the hypogastric nerve bilaterally. Two mechanisms to explain this phenomenon were found ; one is compensation by the sympathetic nerve pathway included in the pelvic nerve originated from the lumbo-sacral sympathetic trunk and the other is sprouting of the preganglionic neuron in the pelvic nerve to the postganglionic neuron in the hypogastric nerve at the pelvic plexus. Ho
rmonal control of sperm transport by the greater splanchnic nerve-adrenal medulla system was highly suspected.
II.The mechanism of sperm trasport through the vas deferes.
Direct electrical stimulation of any site of the cauda epididymis and vas deferens caused elevation of the intraluminal pressure only at the cauda epididymis, whereas stimulation of the testis, caput, and corpus epididymis caused no response. The dye instilled in the cauda epididymis was emitted into the urethra during the stimulation. Shortly after discontinuation of the stimulation, retrograde movement of residual dye in the vas deferens resulted in its ultimate reentry into the cauda epididymis. Distention of the wall of the vas generated elevation of the intraluminal pressure only at the site distended. The above results indicate the presence of rapid antegrade and retrograde movement of the sperm and crucial role of the cauda epididymis on the sperm transport.
III.Anastomosis of the autonomic nerve.
Function of the seminal tract including the vas deferens, bladder neck and prostate, was restored after transection and immediate microsurgical end-to-end suture of the hypogastric nerve.
IV.A new method to generate canine seminal emission and its application to men : Direct electrical stimulation of the vas deferens.
Stimulation of the vas deferens of patients with emission loss elicited seminal emission from the ejaculatory orifice and motile spermatozoa were obtained. Less
Research Output (8results)