Effect of remote ischemic preconditioning on rat estradiol serum levels and follicular development after ovarian transplantation.

PURPOSE: The purpose of this study was to evaluate estradiol serum levels and follicular development in rats subjected to ovarian autologous transplantation with or without remote ischemic preconditioning (R-IPC). METHODS: Seventy-two adult female Wistar EPM-1 rats were distributed into 3 groups: (1) controls; (2) ovarian transplantation; and (3) ovarian transplantation + R-IPC. The groups were divided into subgroups, according to the prefixed date for euthanasia: 24 hours, 48 hours, 72 hours, and 7th postoperative day (PO). R-IPC was performed by clamping the common iliac artery for a 15-minute period of ischemia followed by 15 minutes of reperfusion, before undergoing ovarian transplantation. The graft was fixed to the retroperitoneum with a simple 8-0 prolene thread. Blood samples were collected from the vena cava. For evaluation of follicular development, the ovarian follicles were classified as immature and mature follicles besides corpora lutea. Only the viable follicles and functioning corpora lutea were counted. RESULTS: At 72 hours, the R-IPC group showed higher estradiol values than the other groups, which were similar. After 24 hours the mean values were similar among all groups, and at 48 hours the R-IPC group was similar to the transplanted group without IPC. Animals undergoing R-IPC showed superior morphologic aspects, but 7 days after transplantation the morphology was worse in all groups. R-IPC enhanced the number of immature follicles at 48 hours (P > .05) and number of mature follicles from 24 hours to 48 hours after transplantation (P < .01). Functioning corpora lutea number was increased as well. CONCLUSION: R-IPC increased the estradiol levels in autologous ovarian transplants associated with better graft morphology and more mature follicles.

Maximal inflammatory response benefits syngeneic skin graft acceptance.

OBJECTIVE AND DESIGN: We investigated the influence of acute inflammation in skin isograft acceptance. METHODS: Two mouse lines selected for maximal (AIRMAX) or minimal inflammatory response (AIRMIN) were transplanted with syngeneic skin. Cellular infiltrates and cytokine production were measured 1, 3, 7 or 14 days post-transplantation. The percentage of CD4+CD25+Foxp3+ cells in the lymph nodes was also evaluated. RESULTS: Grafts were totally accepted in 100% of AIRMAX and in 26% of AIRMIN mice. In the latter, partial acceptance was observed in 74% of the animals. Emigrated cells were basically PMN and were enhanced in AIRMAX transplants. IL-10 production by graft infiltrating cells showed no interline differences. IFN-gamma was increased in AIRMIN grafts at day 14 and lower percentages of CD4+CD25+Foxp3+ cells in the lymph nodes were observed in these mice. CONCLUSIONS: Our data suggest that differences in graft acceptance might be due to a lack of appropriate regulation of the inflammatory response in AIRMIN mice compromising the self/non-self recognition.

Pravastatin decreases cold ischemia--but not alloantigen-dependent transplant arteriosclerosis.

BACKGROUND: Alloantigen mismatch and cold ischemia have been shown to induce transplant arteriosclerosis. Pravastatin (PR) decreases arteriosclerosis probably related to an immunosuppressive effect. Statins possess other nonimmune properties that may be beneficial to transplantation. We studied the effect of PR on cold ischemia and alloantigen-induced transplant arteriosclerosis in syngeneic (SYN) and allogeneic (ALLO) aortic transplantation models. METHODS: Lewis rats served as the donors and recipients for SYN transplants and Brown Norway rats were donors for ALLO transplants. Aortic segments that had been preserved at 4 degrees C in Euro-Collins solution for 0 or 24 hours were transplanted to the infrarenal aorta of the recipients PR (10 mg/kg/d) was administered for 12 weeks prior to morphometric studies. Areas of intimal thickness and its relation to total vessel area were calculated. Lipid levels were measured at 12 weeks. RESULTS: Aorta rings preserved for 24 hours showed marked intimal thickening compared to controls (SYN, CI 0 hours = 21.5% +/- 16.5% vs SYN, CI 24 hours = 50.7 +/- 9.5%, P <.05). PR significantly decreased thickening (SYN, CI 24 hours + PR = 41.7 +/- 12.2 (P <.05) vs SYN, CI 0 hours on SYN, CI 24 hours). There was a nonsignificant decrease in thickening among ALLO transplants treated with PR (ALLO = 31.4 +/- 15.9 vs ALLO + PR = 23.8 +/- 18.8; P >.05). PR had no effect on lipid levels. PR decreases cold ischemia induced transplant arteriosclerosis in this syngeneic aortic transplant model, but does not affect an alloantigen-mediated process. The beneficial effect of PR is not related to its lipid-lowering properties but probably to a nonimmune effect.