Glutamate exocrine dynamics augmented by plasma glutamine and the distribution of amino acid transporters of the rat pancreas

D. Fukushima, H. Doi, K. Fukushima, K. Katsura, N. Ogawa, S. Sekiguchi, K. Fujimori, A. Sato, S. Satomi, K. Ishida, K. Fukushima

Research output: Contribution to journalArticlepeer-review

12 Citations (Scopus)

Abstract

The nutritional and physiological roles of amino acid (AA)s have been investigated for individual organs. In the current study, we focused on the dynamics of glutamate and transport systems in the pancreas. We employed original procedures to obtain rat pancreatic juice (PJ) subjected to intravenous administration of alanyl-glutamine (AG) for AA analysis. The pancreatic expressions of the transporters were evaluated by immunohistochemistry. We found that glutamate was secreted into the PJ in the basal state. The intravenous administration of AG increased the concentration and total amount of glutamate excreted into the PJ. In terms of the transport systems, L-type AA transporter (LAT1) was identified exclusively in the islet cells. Glutamate transporter 1 (GLT1), glutamate-aspartate transporter (GLAST), vesicular glutamate transporter 1 (VGUT1) and cystine/glutamic acid transporter (xCT) were found in the islet cells. xCT was identified in the duct cells as well, but was not accompanied by the expression of 4F2 heavy chain (4F2hc) staining in the islets and the acinar cells, similar to neutral AA transporter (ASCT2) or b0,+-type AA transporter 1(BAT1). Excitatory AA transporter (EAAC) was identified only in the acinar cells. Glutamate was exclusively found in the acinar cells. We revealed the novel dynamics of glutamate in the rat PJ. The glutamate secretion into the PJ was augmented by plasma glutamine, indicating the de novo metabolisms of glutamate, together with the local expression of the related transporters.

Original languageEnglish
Pages (from-to)265-271
Number of pages7
JournalJournal of Physiology and Pharmacology
Volume61
Issue number3
Publication statusPublished - 2010 Jun

Keywords

  • Amino acid
  • Exocrine
  • Glutamate
  • Glutamine
  • Pancreas
  • Pancreatic juice
  • Transporter

ASJC Scopus subject areas

  • Physiology
  • Pharmacology

Fingerprint Dive into the research topics of 'Glutamate exocrine dynamics augmented by plasma glutamine and the distribution of amino acid transporters of the rat pancreas'. Together they form a unique fingerprint.

Cite this