ABSTRACT
Objective: To investigate the feasibility of repairing nerve defect of sciatic nerve in rats by the pretreatment of cold preservation with tetramethylpyrazine. Methods: Forty Wistar rats and 40 SD rats were selected as donors and recipients, respectively [3 months, SPF male rat (200 ± 20) g], the sciatic nerve segments of 15 mm were harvested from the donors, then randomly preserved in 4℃ tetramethylpyrazine solution (0, 50, 100, and 200 mg/L, in A, B, C, and D groups, n = 20) for 6 weeks, the ultrastructure of sciatic nerve was observed by transmission electron microscope (TEM). Calcein-AM staining was used to observe the change of fluorescence intensity with laser scan confocal microscope (LSCM). The recipients were randomly divided into A′, B′, C′, and D′ groups (n = 10, corresponding to A, B, C, and D groups), 10 mm defect of sciatic nerve in recipient was repaired by the nerve preserved for 6 weeks. The gross appearance and sciatic nerve function index (SFI) were detected at different period after the surgery. The electrophysiological changes, regenerated nerve image analysis, and TEM were performed in 20 weeks after transplantation. Results: The nerve preserved for 6 weeks, there were severe demyelination and neuraxis denaturation in group A, but these changes in groups B, C, and D were more gentle than those in the group A. The fluorescence intensity in the groups B, C, and D was higher than that in group A, and in group B higher than that in groups C and D (P 0.05). All the rats survived to the end of the experiment. There were significant differences (P 0.05) in different times of SFI after transplantation, electrophysiological detection, the number of myelinated nerve fibers, and thickness of myelin at 20 weeks, The observation of TEM in 20 weeks showed that myelinated nerve fibers and thickness of myelin sheath in group A′ was thinner than those in groups B′, C′, and D′, and that the hyperplasia of connective tissues in group A′ was more serious than that in groups B′, C′, and D′. Conclusion: Tetramethylpyrazine plays a protective role on the cold preservation of sciatic nerve, and could promote the nerve regeneration after allogeneic transplantation.
ABSTRACT
<p><b>OBJECTIVE</b>To study the effect of Shengjingsan on spermatogenic function following testicular torsion/detorsion in rats and its action mechanism.</p><p><b>METHODS</b>Forty SD male rats were equally randomized to groups A (sham operation), B (control), C (low-dose Shengjingsan), D (medium-dose Shengjingsan) and E (high-dose Shengjingsan). The model of testicular torsion was established by 720 degrees clockwise torsion of the left testis for 4 hours. An hour before operation, the rats of group B received daily gavage of normal saline at 1 ml per kg per d, while those in groups C, D and E that of Shengjingsan at 0.01, 0.02 and 0.03 g per kg per d, all for 35 days. Then all the rats were sacrificed for measuring the semen parameters by CASA and detecting the expression of the CatSper1 gene in the sperm by RT-PCR.</p><p><b>RESULTS</b>Compared with group A, Sperm concentration, the percentage of grade a + b sperm, sperm vitality and CatSper1 expression were significantly lower in group B ([15.30 +/- 6.30] %, [44.42 +/- 6.36] %, [21.00 +/- 6.14] x 10(6)/ml and 1.12 +/- 0.50) than in A ([51.30 +/- 6.60]%, [69.01 +/- 7.20]%, [40.53 +/- 7.01] x 10(6)/ml and 2.04 +/- 0.77) (P < 0.01). Compared with group B, the four parameters were increased remarkably in groups D ([51.63 +/- 3.20] %, [72.09 +/- 2.20]%, [55.30 +/- 5.90] x10(6)/ml and 2.11 +/- 0.20) andE ([55.93 +/- 3.17]%, [73.01 +/- 2.11]%, [58.33 + 4.90] x 10(6)/ml and 2.31 +/- 0.17) (P < 0.01), but not significantly in C ([18.02 +/- 0.23]%, [48.04 +/- 7.01]%, [22.87 +/- 2.10] x 10(6)/ml and 1.19 +/- 0.51) (P > 0.05).</p><p><b>CONCLUSION</b>Shengjingsan can improve sperm parameters following testicular torsion/ detorsion in male rats by regulating their spermatogenic function and improving the expression of CatSper1 in the sperm.</p>