Blood flow in endogenous and transplanted pancreatic islets in anesthetized rats: Effects of lactate and pyruvate
2012 (English)In: Pancreas, ISSN 0885-3177, E-ISSN 1536-4828, Vol. 41, no 8, 1263-1271 p.Article in journal (Refereed) Published
OBJECTIVE: The objective of this study was to evaluate the effects of exogenously administered lactate and pyruvate on blood perfusion in endogenous and transplanted islets. METHODS: Anesthetized Wistar-Furth rats were given lactate or pyruvate intravenously, and regional blood perfusion was studied 3 or 30 minutes later with a microsphere technique. Separate rats received a 30-minute infusion of pyruvate or lactate into the portal vein before blood flow measurements. We also administered these substances to islet-implanted rats 4 weeks after transplantation and measured graft blood flow with laser Doppler flowmetry. The expression of monocarboxylate transporter 1 and lactate dehydrogenase A was analyzed. RESULTS: The expression of monocarboxylate transporter 1 and lactate dehydrogenase A was markedly up-regulated in transplanted as compared with endogenous islets. Administration of pyruvate, but not lactate, increased mesenteric blood flow after 3 minutes. Pyruvate decreased mesenteric blood flow after 30 minutes, whereas lactate decreased only islet blood flow. These responses were absent in transplanted animals. A continuous intraportal infusion of lactate or pyruvate increased selectively islet blood flow but did not affect blood perfusion of transplanted islets. CONCLUSIONS: Lactate and pyruvate affect islet blood flow through effects mediated by interactions between the liver and the nervous system. Such a response can help adjust the release of islet hormones during excess substrate concentrations.
Place, publisher, year, edition, pages
2012. Vol. 41, no 8, 1263-1271 p.
blood flow, lactate, pancreatic islets, pyruvate
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-186004DOI: 10.1097/MPA.0b013e31824bd97cISI: 000310360500015OAI: oai:DiVA.org:uu-186004DiVA: diva2:572706