PURPOSE: To evaluate the effect of hyperbaric oxygen therapy on the survival and weight of rats submitted to subtotal splenectomy and on the viability and growth of the inferior pole. METHODS: Forty Wistar rats underwent subtotal splenectomy with preservation of the inferior pole and distributed into two groups: Group A (n=20) - not treated with hyperbaric oxygen, Group B (n=20) - treated with hyperbaric oxygen. These groups were divided into two subgroups of 10 animals each, according to the time of euthanasia, 15th and 45th days. The survival and weight of the animals were recorded. The inferior pole was measured, weighed and morphologically analyzed. RESULTS: All animals survived. The weight of the animals increased in all subgroups, but decreased on the 10th day in the subgroups treated with hyperbaric oxygen (p<0.001). The viability of the inferior pole was more evident in animals treated on the 15th day, but did not differ on the 45th day. The growth of the inferior pole has not occurred on the 15th day but on the 45th day after surgery in untreated animals (p<0.01) and treated animals (p<0.05). Vascular and cellular increase in treated animals was significantly higher than in untreated ones. CONCLUSION: Hyperbaric oxygen therapy did not affect the survival of animals but reduced their weight. It improved the viability of the inferior splenic pole, but did not interfere with their growth.

PURPOSE:To analyze total splenectomy effect on the lipid profile -total cholesterol, low-density lipoprotein cholesterol (LDL), highdensity lipoprotein cholesterol (HDL), very-low-density lipoprotein cholesterol (VLDL) and triglycerides levels, in Balb/c mice. METHODS:Thirty Balb/c male mice, one (1) month old and average weight 26.2g ± 4.0 were used in the experiment. They were distributed into three groups of 10 animals each: a control group (non-operated), a simulation group (spleen manipulation) and the splenectomy group. The animals were subjected to blood sampling to measure plasma lipid levels, at three different times: before surgery, days 30 and 75 of the experiment. RESULTS:Increased total cholesterol and LDL were observed in the control group from the start to end of the experiment. The simulation group showed increased rates of VLDL and triglycerides at the 30th and 75th days. Splenectomized animals showed no significant change. CONCLUSION:Total splenectomy did not induce increased plasma lipids levels of in Balb/c mice.

PURPOSE:To analyze PCNA immunoexpression on the inferior pole of the spleen of splenectomized rats submitted to hyperbaric oxygenation (HBO). METHODS:Were analyzed fragments of the inferior pole of the spleen of 20 male Wistar rats submitted to splenectomy with preservation of the inferior pole. The rats were divided in two groups: group A (n=10) without HBO and group B (n=10) submitted to HBO at 2, 5 atmospheres per 120 minutes, twice a day for three days and once a day for seven days. The groups were then subdivided in four subgroups: A15 (n=5), with euthanasia on the 15 th day; A45 (n=5), with euthanasia on the 45 th day; B15 (n=5) with euthanasia on the 15 th day and B45 with euthanasia on the 45 th day. Respectively on these days, fragments of the inferior pole of the spleen of all animals were collected and analyzed with the immunohistochemistry technique in order to evaluate PCNA expression. RESULTS:There was an expressive increase in PCNA immunoreactivity in the group B. The 45 day postoperative period resulted in a higher level of positivity than the 15 day postoperative period (p<0.01). CONCLUSION:The quantitative analysis of proliferating cell nuclear antigen positive suggests that hyperbaric oxygenation increases cellular proliferation, contributing to splenic regeneration.

Comparing survival rates of rats subjected to spleen procedures after fecal peritonitis induction. Assessing changes in TCD4 and CD8 lymphocyte rates before and after the procedures. Correlating animal survival with CD4 and CD8 lymphocytes. Methods: Thirty male Wistar rats were distributed into 3 groups of ten: spleen manipulation (SM); total splenectomy (TS); subtotal splenectomy with preservation of the inferior pole (IP). Rats were subjected to surgical procedure depending on the group. Seven days after surgery they underwent induction of peritonitis and survival time was recorded. All animals were subjected to two blood collections: before surgery and 70 days after it for TCD4/TCD8 lymphocyte counting. Results: Mean survival time was longer in the IP and SM groups and shorter in the TS group; there was significant difference between them. The comparison of the median number of CD4 did not present changes, whereas the comparison of the median number of CD8 decreased in the SM and IP groups. The correlation between the median number of TCD4 and TCD8 lymphocytes and the animals' survival was not significant. Conclusion: The maintenance of splenic tissue contributed to increase the survival of rats and there was a change in the number of TCD8 lymphocytes.

Purpose To evaluate the viability of the upper (UP) and lower pole (LP) of the spleen from a macro and microscopic point of view, after subtotal splenectomy with preservation (SSP) of the UP and the LP. Methods Seventeen male Wistar rats, two months old, were submitted to SSPUP and SSPLP and 5 to simulated operation (SG). After 80 days, the rats were euthanized, and the remaining LP and UP and intact spleens were evaluated macroscopically and microscopically. Results Two rats died during the operation. Macroscopic analysis showed that in 15 LP, one of them was not viable and in 15 UP and in 5 spleens in the SG, all were viable. In the statistical analysis, there was no difference in relation to viability. The LP and UP analyzed showed variation. As for the length, the UP increased significantly; however, in relation to the width, there was a significant increase in the LP in relation to the UP. In addition, the weight of the UP was significantly greater than that of the LP. Microscopic analysis attested viability of the splenic remnants. Conclusion There was no significant difference regarding the viability of UP and LP, in macroscopy and microscopy.