大鼠面神经切断和切断修复后面神经核内鞘脂激活蛋白原的变化

BACKGROUND： Studies have demonstrated that damaged facial nerves synthesize prosaposin to promote repair of facial neurons. OBJECTIVE： To observe time-course changes of prosaposin expression in the facial nerve nucleus of Sprague Dawley rats following facial nerve transection and repair. DESIGN, TIME AND SETTING： A randomized control neuropathological animal experiment was performed in Chongqing Medical University between March 2007 and September 2008. MATERIALS： A total of 48 adult, male, Sprague Dawley rats were selected and randomly divided into transection and transection ＋ end-to-end anastomosis groups （n =24）. Rabbit anti-rat prosaposin antibody, instant SABC immunohistochemical kit, and antibody dilution solution were purchased from Wuhan Uscn Science Co., Ltd., China. METHODS： In the transection group, the nerve trunk of the distal retroauricular branch of the left facial nerves was ligated in Sprague Dawley rats, and a 5-mm nerve trunk at the distal end of the ligation site was removed. In the transection ＋ end-to-end anastomosis group, epineurial anastomosis was performed immediately following transection of the left facial nerves. The right facial nerves in the two groups served as the normal control group. MAIN OUTCOME MEASURES： The number of prosaposin-positive neurons, as welt as intensity of immunostaining in facial nerve nucleus, following transection and end-to-end anastomosis were determined by immunohistochemistry at 1, 3, 7, 14, 21, and 35 days after injury. RESULTS： Transection group： transection of facial nerves resulted in increased number of prosaposin-positive neurons and immunoreactivity intensity in the facial nucleus on day 1. These values significantly increased by day 3. Expression was greater than in the control side. The peak of the reduction was reached at 7 days post-surgery. Transection ＋ end-to-end anastomosis group： the number of prosaposin-positive neurons and immunoreactivity intensity was reduced in the facial nerve nucleus following immediate end-to-end anastomosis on day 7 post-surgery. These values began to gradually increase by day 14 post-anastomosis. By day 35 post-anastomosis, the number of prosaposin-positive neurons in the operated side recovered to normal levels. The number of prosaposin-positive neurons, as well as immunoreactivity intensity, was significantly greater in the facial nerve nucleus, compared with the transection group on days 14, 21, and 35 post-surgery （P 〈 0.05）. The rhythmic whisking of vibrissa recovered, and recovery time was consistent with increased numbers of prosaposin-positive neurons. CONCLUSION： Within 7 days after injury, prosaposin expression in the facial nerve nucleus exhibited an initial increase, followed by a decrease, and was not affected by facial nerve repair. Following facial nerve damage, neural anastomosis was shown to increase prosaposin expression in the facial nerve nucleus after 14 days. Recovery of prosaposin occurred simultaneously with reinnervation.

Altered prosaposin expression in the rat facial nerve nucleus following facial nerve transection and repair

Objective:To observe the changes of prosaposin in the rat facial nerve nucleus following the facial nerve transection and repair.Methods:48 adult male SD-rats were randomly divided into 2 groups.Rats in the experimental groups were made into lateral facial injury models of cut and end-to-end anastomosis after immediate transection .we examine the number of prosaposin-positive neurons and the intensity of immunostaining in adult male SD rat facial nerve nucleus following the peripheral nerve transection (A group)and end-to-end anastomosis after immediate transaction(B group) by immunohistochemistry.The brainstems were taken at 1,3,7,14,21 and 35 days after injury.The Prosaposin was detected with immunohistochemical staining,and counting of amount of the positive cells staine by Prosaposin under light microscope. Results:A group:The transection of peripheral nerve resulted in a increase in both the number of prosaposin-positive neurons and the intensity of immunoreactivity in adult rat facial nucleus on the operated side at 1 day.These values on the operative side began to increase obviously at 3 day.The peak of the reduction was reached at 7 day post operation.B group:The patterns of reduction in both the number of prosaposin-positive neurons and the intensity of immunoreactivity in adult rat facial nerve nucleus following the peripheral nerve immediate end-to-end anastomosis after transection with 7 days post operation were similar to A group(P>0.05).These values on the operative side started to increase gradually on day 14 post-anastomosis.At 35 day post-anastomosis , the number of prosaposin-positive neurons on the operative side approximately recovered to normal level. The amount of the positive cells stained by Prosapoin in facial nucleus and the intensity of immunoreactivity in facial nucleus were significantly different at 14, 21 and 35 days after operating between the two groups(P<0.05). Concluions:These results indicated that the suture of facial nerve can increase in the level of expression in adult rat facial nucleus In the later stage . The repair of facial nerve can promote the synthesis of Prosaposin in facial nucleus after facial nerve injury. The repair of facial nerve can not be prevention of the level of expression in adult rat facial nucleus after facial nerve injury on the early stage side of the facial nerve nuclear Prosaposin positive product of Immunization decline The increase of prosaposin level may be related with the process of facial nerve axon regenereation.