Objective To investigate the effects of 17β-estradiol on the cell apoptosis after chronic spinal cord injury in ovariectomized rats. Methods A total of 90 female Wistar rats (weighing, 220-250 g) received removal of bilateral ovaries. After 2 weeks, the rats were randomly divided into 3 groups (n=30): sham-operation group (group A); chronic gradual spinal cord injury model and 17β-estradiol treatment group (group B); and chronic gradual spinal cord injury model and normal saline treatment group (group C). Rats of group A only received removal of spinous process at T10. Rats of groups B and C were made the models of chronic gradual spinal cord injury, and then 17β-estradiol (100 μg/kg, twice a week) and normal saline were given by peritoneal injection, respectively. The cell apoptosis and positive cells of Caspase-3 were examined by the TUNEL methods and Caspase-3 immunohistochemical staining at 1, 3, 7, 14, 28, and 60 days after modeling; and the neurological function was evaluated by Tarlov scale and inclined plane test scoring. Results At 14, 28, and 60 days after modeling, Tarlov scale and inclined plane test scores of group B were significantly better than those of group C (P lt; 0.05), but were significantly lower than those of group A (P lt; 0.05). At 28 days after modeling, HE staining showed that the edema of spinal gray matter and the neurons, the proliferation of glial cells and astrocytes, and less pathologic change were observed in group B; and the pathological changes in group B were mitigated than in group C. At 60 days after modeling, edema of spinal gray matter and the neurons was significantly ameliorated in group B. At 14, 28, and 60 days after modeling, the rate of Caspase-3 positive cells in group B was significantly lower than in group C (P lt; 0.05), but was significantly higher than in group A (P lt; 0.05). At 7, 14, 28, and 60 days after modeling, the cell apoptotic rate was significantly lower in group B than in group C (P lt; 0.05), but was significantly higher than in group A (P lt; 0.05). Conclusion 17β-estradiol can reduce the numbers of apoptotic cells and promote the nerve function recovery after chronic spinal cord injury of rats.
Objective This study aimed to observe the protective effects of 17β-estradiol (17β-E2) to the damage of phenobarbital (PB) upon the cognition of the newly-born rats. Methods Thirty healthy 3-day-old Sprague Dawley (SD) rats were randomly divided into 3 groups: control group (10 rats), PB group (10 rats) and PB+17β-E2 group (10 rats). The control group were injected saline water with a dose of 10 mL/(kg·d); the PB group were injected with PB of 10 mg/(kg·d); the PB+17β-E2 group were injected with PB 10 mg/(kg·d) and 17β-E2 300 ug/(kg·d). All the rats were intraperitoneal injected once a day after weighing, for three continuous days. They were normally raised to one month old and then 8 rats were selected out of each group respectively for water maze test. Results The PB group was reported to have increasing latent periods in finding the underwater stage compared with control group (P<0.05). In comparison with the PB group, the PB+17β-E2 group has a shorter latent period in finding the underwater stage, and furthermore statistically significantly fewer times in finding validation areas (P<0.05). During the 120s test, the stage quadrant journey to total journey ratio of PB+17β-E2 group was lower than the ratio of PB groups, but no statistics significance had been detected. The PB+17β-E2 group exhibits no significance difference from the control group in the above-mentioned indexes. Conclusions Even a short-term injection of PB with an usual clinical dose will bring a long-term damage to an immature brain in terms of the learning ability and memory, whereas the 17β-E2 may play a protective role in this course.