Effect of hyperbaric oxygen therapy in rats with subtotal splenectomy preserving the inferior pole

Abstract

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.

Phagocytic function of lower spleen pole and autogenous splenic implants in rats

“…Once concerned about this possibility, Paul et al 7 performed a subtotal splenectomy preserving the lower spleen pole in dogs, which remained macroscopically feasible in 86.6% of the cases, even with the ligature of the main splenic vessels. 7 The lower polo viability was also observed in rats [8][9][10][11] .…”

Immunoexpression of proliferating cell nuclear antigen (PCNA) in spleen of splenectomized rats with preservation of inferior pole, submitted to hyperbaric oxygenation

“…The animals were randomly divided in two groups according to whether they were submitted or not to HBO and were later subdivided in four groups according to the day of specimen collection of the inferior pole of the spleen for IHC analysis 8 ( Table 1). The spleen superior portion was removed according to Paulo et al.…”

“…Rats submitted to this procedure, followed by hyperbaric oxygenation (HBO) at 100% pure oxygen, in conventional microscopy, showed larger lymphatic follicles, increase of the amount of cells and vessels and more lymphocytic cell proliferation in the inferior pole of the spleen 7,8 . Considering these findings, we proposed to evaluate the immunohistochemistry expression (IHC) of the proliferating cell nuclear antigen (PCNA) which main function is to increase the activity of delta DNA polymerase during DNA replication, event that precedes cell division process 9 .…”

Micronucleus test in peripheral blood of rats treated with hyperbaric oxygen after subtotal splenectomy preserving the lower pole

“…HBO treatment of the rats submitted to subtotal splenectomy with lower pole preservation (ESTPI) enabled the improvements in the lipid function and in the viability of the lower pole when compared with rats not submitted to HBO 2 , as well as the increase in cellular and vascular proliferation 3,4 . For the other hand, HBO has side effects such as pulmonary and neurologic toxicities, auditory barotrauma, discomfort in facial sinuses and temporary visual impairment.…”

“…Due to the important role in micronucleated cells splenic capture and since little is known about the impact of HBO on MN frequency on partially splenectomized animals 16 , we evaluate the mutagenic potential of a HBO protocol by means of a micronucleus test performed in the peripheral blood of Rattus norvegicus Wistar rats submitted to ESTPI, according to techniques already described [17][18][19][20][21] .…”