Shogo Fujita

NEO RED CELL AS AN ORGAN PRESERVATION SOLUTION

Neo red cell (NRC) was derived from outdated human red cells. The following experimental work has been done in order to investigate if NRC is valid for organ preservation. Hearts were obtained from male Lewis rat (250-350 g body weight). Heart transplantation was performed as Ono-Lindseys method after 1, 3, 6, 12 and 24 hours simple cold storage. Rats were divided into two groups. Group 1; original NRC as preservation solution, Group 2; modified NRC (NRC suspended with UW solution) as preservation solution. After 1, 3, and 6 hour cold ischemic storage, the transplanted hearts in both groups showed contraction immediately after declamping the aorta and the pulmonary artery. After 12 and 24 hour preservation, the transplanted hearts in group 2 showed contraction. Myocardial ATP levels after 6, 12, 24 hours cold storage compared with 0 hour were 62.3%, 28.3%, 32.8% in group 1 respectively. On the contrary, myocardial ATP levels were 87.2%, 57.6%, 52.2% in group 2 respectively. After 24 hour preservation, pathological change was not remarkable between the two groups. Results of the prolonged preservation time and the myocardial ATP changes suggest that there is a possibility for effective use of NRC not only as blood substitute but also organ preservation solution.

Modulation of Prostaglandin Metabolism by K-MAP and Prevention of Toxic Effect of Cyclosporin on Pancreatic Islet Cells

The injection of 25 mg/kg i.p. cyclosporin (CsA) for 3 wk caused marked functional and morphological deteriorations of pancreatic islet cells in Wistar rats that were prevented by the combined administration of p-aminobenzoic acid-N-D-mannoside sodium salt (K-MAP). In this article, the toxic effect of CsA on pancreatic islet cells and the preventive effect of K-MAP on CsA-associated islet cell toxicity were investigated. Prolonged hyperglycemia and depressed insulin secretion after the glucose challenge observed in CsA-treated rats could be prevented by the combined administration of 300 and 900 mg/kg K-MAP. Cytoplasmic vacuolizations and a decrease in the number of mitochondria, intact endoplasmic reticula, secretory granules, and insulin-positive cells, as revealed by peroxidase-antiperoxidase staining, could also be prevented by the administration of 900 mg/kg K-MAP. This preventive effect of K-MAP on CsA-associated islet cell toxicity may suggest the combined use of K-MAP with CsA in pancreas transplantation and treatment of insulin-dependent diabetes.

Evaluation of a Pyridoxylated Hemoglobin Polyoxyethylene Conjugate Solution as a Perfusate for Small Intestine Preservation

A new type of artificial blood, pyridoxylated hemoglobin-polyoxyethylene conjugate (PHP) solution, (developed by PHP research group of the department of health and welfare of Japan, and produced by Ajinomoto Co., Inc. Tokyo) as an oxygen-carrying component, has been recently devised using hemoglobin obtained from hemolyzed human erythrocytes. Recently, the studies using this solution as a preservation solution were performed in some instances. To examine the mechanism of improved viability using this solution as a preservation solution, we developed a model of orthotopic small intestine transplantation (OIT) in the rat. As a baseline study, we compared parameters of viability of the grafts preserved in Collins and UW solution to those preserved in PHP solution including a survival rate, a serum level total protein and albumin, and a change in body weight after transplantation. In our study, the simple hypothermia storage together with intestinal perfusion preservation with PHP solution was performed. Animals were divided into 6, 12, and 24 hr preservation groups. All of the rats survived after 6 hr preservation following transplantation. However, in 12 hr storage, five of six rats in PHP solution preservation survived and recovery in body weight after grafting was better than those with Collins and UW solution. We conclude that the PHP solution is, therefore, considered to possibly be a more suitable perfusate for small intestine preservation than Collins and UW solution.