assessment of corn oil as a vehicle for cyclosporine A [CsA] at varied injection sites in preventing rejection of rat laryngeal allografts

ABSTRACT

This study was designed to determine the efficacy of corn oil as an alternative vehicle to olive oil for emulsifying cyclosporine [CsA] in preventing rejection of transplanted rat larynges. The issue of varied site absorption was also addressed. Thirty animals were transplanted to get 5 viable transplants at two weeks for three varied sites of administration; intramuscular [IM, subcutaneous [SQ] and intraperitoneal [IP]. Five mg/kg of CsA in corn oil was the dose administrated based on earlier data generated in our laboratory. Postulating selective absorption, the indirect measure of laryngeal histopathology, i.e. rejection, was chosen over blood levels for evaluation. In the IM group 2 grafts evidenced mild rejection whereas 3 showed marked cellular and vascular rejection. The SQ group had 1 mild, 1 moderate and 3 with severe rejections. The IP group had one moderate rejection and 4 severe rejections. Qualitatively the IM and SQ groups were similar. The IP group histologically evidenced far greater cellular rejection. CsA 5mg/kg emulsified in corn oil did not differ substantively in histologic scope or pattern of rejection from CsA in olive oil in experimental rat laryngeal transplantation. Further, the data did not support a change in the administration of CsA from an intramuscular site