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S Rahimi-Saber

Publications and source records attributed to S Rahimi-Saber.

6 recordsLinked to original sources
PubMed1996

Pancreas autotransplantation in pig with systemic or portal venous drainage. Effect on the endocrine pancreatic function after transplantation.

The effect of the type of venous drainage of the graft on its endocrine function was studied in two groups of pigs after segmental pancrease autotransplantation. Group 1 comprised 10 pigs with portal venous drainage (PVD) and group 2 comprised 10 pigs with systemic venous drainage (SVD). The graft consisted of body and tail of the pancreas. The pigs were totally pancreatectomized. The pancreatic duct was occluded by neoprene injected into the duct. One week before and 1 and 3 months after transplantation, intravenous glucose tolerance (IVGTT) and meal stimulation tests (MST) were performed. Plasma glucose (PG), insulin (INS), C-peptide, glucagon (GLU),and pancreatic polypeptide (PP) were measured during the tests. All pigs had normal fasting PG, 1 and 3 months after PanTx, although MST disclosed significantly higher PG (P<0.05) during the test after transplantation. In the PVD group, a decrease in INS level during both test was recorded after PanTx (P<0.05), while in the SVD group a nonsignificant rise in INS level was recorded compared with before transplant. A significant difference (P<0.05) in INS levels were present both 1 and 3 mon. after PanTx between the two groups. Pigs with PVD showed a higher (P<0.05) C-peptide level than pigs with SVD during IVGTT. The initial significant rise in PP during MST and the initial fall in PP during IVGTT recorded in all pigs before transplantation were totally lost after transplantation in both groups. During the tests, PP remained steady and significantly lower than the pretransplantation levels in both groups. A significantly higher GLU level during both IVGTT and MST was observed in SVD compared with PVD 1 month after PanTx (P<0.05), being more pronounced during MST. This accentuated GLU concentration decreased by 3 months after transplantation, although it was still significantly greater than pretransplantation levels. We concluded that the unnatural mode of delivery of pancreas endocrine secretion to systemic rather than to portal circulation leads to derangements in pancreatic endocrine function in order to maintain glucose homeostasis. This may cause earlier exhaustion of islet cells. Segmental rather than whole organ and duct occlusion rather than exocrine drainage may further contribute to this, shortening the effective life of the graft.

Animals↗
PubMed1992

Autotransplantation of splenic tissue in an isolated segment of small intestine.

The ability of splenic tissue to regenerate when implanted in an isolated segment of small intestine with intact circulation was studied in six pigs. After total splenectomy, 10 per cent of the weight of the spleen was implanted in a 10-15-cm long isolated segment of small intestine with an intact vascular supply. Bowel continuity was established by end-to-end anastomosis. Before implantation, the mucosal layer was completely removed from the isolated segment of the small intestine. The animals were killed 6 months later and the isolated segment of small bowel containing the splenic tissue identified. Most of the implanted splenic tissue was recovered in the isolated segment of small intestine; the weight ranged from 43 to 120 (mean 80) per cent of that of the implanted tissue. An isolated segment of small intestine with an intact circulation produces a higher index of regeneration than other previously reported sites.

Animals↗
PubMed1990

Phagocyte function after splenic autotransplantation.

This study was designed to examine the role of splenectomy and autotransplantation with regard to the leukocyte/differential cell counts and the function of peripheral blood phagocytes. Eleven groups of 40 Wistar male rats in each group either underwent total splenectomies or sham operations. The splenectomized groups underwent autotransplantations with 10% through 90% of the weight of the intact spleen. The leukocyte count and the oxidative burst response of the blood leukocytes were measured in each group. It was shown that a total splenectomy did not alter the leukocyte/differential cell counts. Furthermore, the blood picture remained basically unchanged after an autotransplantation with 10% through 90% of the weight of the intact spleen. The phagocyte oxidative burst response was measured by chemiluminescence. The chemiluminescence response of these cells was reduced after a total splenectomy. The phagocyte oxidative burst response returned to normal levels following an autotransplantation. There was no correlation between the amount of autotransplanted spleen and the degree of the oxidative burst response. These findings indicated that a splenectomy results in a diminished phagocyte oxidative burst response and that a spleen autotransplantation returns this function to normal levels.

Animals↗
PubMed1990

Does survival depend on the amount of autotransplanted splenic tissue?

Susceptibility to Streptococcus pneumoniae infection was studied in 11 groups of rats allocated to sham operation, splenectomy, or splenic autotransplantation of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90% of the removed spleen. Three months later, all rats were exposed intravenously to type 1 Streptococcus pneumoniae (median lethal dose, LD50, for control group). Survivors were killed 13 days after the bacterial challenge. Autopsy showed that more splenic tissue was recovered in rats that received less than 50% splenic tissue compared with those that received 50% or more. More survivors were found among sham-operated rats (47.5%; 95% confidence intervals, 32 to 68) and rats that had 40% splenic tissue implanted (35%; confidence interval, 20 to 54) or those that were found to have regenerated 40% splenic tissue. We conclude that 40% of the spleen should be autotransplanted to protect the rat optimally against infection after splenectomy.

Animals↗
PubMed1989

Segmental pancreatic autotransplantation in the pig.

The pig has been considered unsuitable for experimental pancreatic transplantation. In order to develop a model for segmental transplantation, the vascular anatomy was studied in 41 pigs. No variation in venous drainage of the pancrease was found. In contrast, 3 variations of arterial supply were noted. In 29 of the pigs (71% [95% confidence limits 64-84]), 1 main pancreatic artery to the body and tail of pancreas arose from the splenic artery about 1-2 cm from its origin from the coeliac trunk (type 1). In 6 pigs (14.5%, 6.5-29.2), 1 main pancreatic artery emerged from the splenic artery very close to its origin from coeliac trunk (type 2). In 6 pigs (14.5%, 6.5-29.2), the only pancreatic artery supplying the body and tail of pancreas came from the common hepatic artery (type 3). Taking the vascular anatomy into account, 37 pigs were totally pancreatectomized and autotransplanted segmentally. The graft consisted of the body and tail and corresponded to approximately 60% of the entire gland. The pancreatic duct was occluded with neoprene. The left kidney was removed in all animals. In 19 of the grafts, the venous drainage was to the portal vein. In the remaining 18, the renal vessels were used for vascular anastomosis to the graft. The success rate was 68.42% and 72.22%, respectively. The median follow-up was 9 months (3-15). All transplanted pigs were normoglycemic. It is concluded that the pig is suitable for experimental pancreatic autotransplantation studies if the vascular variations are adequately dealt with.

Animals↗