Reconstruction of the sympathetic pathway projecting to the prostate, by nerve grafting in the dog
Nobuhiko Hyochi1, Kazunori Kihara, Gaku Arai
1Urology and Reproductive Medicine, Tokyo Medical and Dental University, Graduate School, Tokyo, Japan. h-yuc.uro@tmd.ac.jp
Objectives:
To examine the possibility of nerve grafting to repair the sympathetic pathway projecting to the prostate, as contraction of the prostate is known to be controlled by the sympathetic pathway via the hypogastric nerve (HGN), and injuries to the pathway cause significant disturbances in prostatic secretion.
Materials And Methods:
In six dogs both of the HGNs were partly removed and immediately repaired with an autologous nerve graft. The left HGN was repaired with a colonic (autonomic) nerve graft and the right with a genitofemoral (somatic) nerve graft. Twenty months after surgery the reconstruction of the sympathetic pathway was assessed by measuring contraction of the prostate after stimulating the lumbar splanchnic nerves (LSNs).
Results:
Nine of the 17 right LSNs stimulated elicited prostatic contractions. After transecting the left HGN five of these nine responses were restored. Seven of the 11 left LSNs stimulated elicited prostatic contractions; after transection of the left HGN four of these seven responses were preserved.
Conclusion:
The sympathetic pathways via the HGN to the canine prostate can be reconstructed by nerve grafting, regardless of the use of autonomic or somatic nerve grafts, and the cross-innervation mechanism from the LSN to the prostate can also be repaired.
