The effects of vasoactive intestinal peptide (VIP) on intestinal secretion have been well characterized. Clinically, tumors producing VIP are responsible for the syndrome of watery diarrhea, hypokalemia and gastric achlorhydria described by Verner and Morrison. However, the interaction between VIP and its receptor on the target cell, the first step responsible for specific signal transduction, has only recently been examined. With the groundwork laid by our previous studies on the structural on the intestinal VIP receptor, we plan to: 1. Raise monoclonal and polyclonal antibodies against the VIP receptor using the purest receptor preparation available (see below). 2. Purify the VIP receptor relying mainly on gel filtration and affinity chromatography (using either VIP or antibodies against the receptor). If required, reconstitute the purified receptor into liposomes to define its function. 3. Using different endoglycosidases, study the degree and type of glycosylation of the VIP receptor located on the ER-Golgi and laterobasal membranes of the enterocyte. With the panel of monoclonal antibodies described in 1, attempt to correlate a function or structure to each domain of the receptor. 4. Study the synthesis, glycosylation, vectorial processing and transport of the metabolically radiolabeled VIP receptor in pulse chase experiments using the isolated intestinal loop. 5. With the intestinal loop or the human colonic adenocardinoma cell line, HT 29, study the cellular cycle of the receptor (internalization, degradation, recycling).

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
5R29DK040506-02
Application #
3463556
Study Section
Endocrinology Study Section (END)
Project Start
1988-08-01
Project End
1993-07-31
Budget Start
1989-08-01
Budget End
1990-07-31
Support Year
2
Fiscal Year
1989
Total Cost
Indirect Cost
Name
Duke University
Department
Type
Schools of Medicine
DUNS #
071723621
City
Durham
State
NC
Country
United States
Zip Code
27705
Nguyen, T D; Wolfe, M S; Heintz, G G (1995) Solubilization of receptors for pancreatic polypeptide from rat liver membranes. Am J Physiol 268:G215-23
Nguyen, T D; Canada, A T (1994) Modulation of human colonic T84 cell secretion by hydrogen peroxide. Biochem Pharmacol 47:403-10
Nguyen, T D; Heintz, G G; Wolfe, M S (1993) Structural characterization of PACAP receptors on rat liver plasma membranes. Am J Physiol 265:G811-8
Nguyen, T D; Canada, A T (1993) Citrus flavonoids stimulate secretion by human colonic T84 cells. J Nutr 123:259-68
Nguyen, T D; Wolfe, M S; Heintz, G G et al. (1992) High affinity binding proteins for pancreatic polypeptide on rat liver membranes. J Biol Chem 267:9416-21
Nguyen, T D; Heintz, G G; Cohn, J A (1992) Pituitary adenylate cyclase-activating polypeptide stimulates secretion in T84 cells. Gastroenterology 103:539-44
Nguyen, T D; Canada, A T; Heintz, G G et al. (1991) Stimulation of secretion by the T84 colonic epithelial cell line with dietary flavonols. Biochem Pharmacol 41:1879-86
Taylor, I L; Mannon, P J; Heintz, G G et al. (1990) Comparison of the neuropeptide Y receptor in the rat brain and intestine. Ann N Y Acad Sci 611:48-57
Nguyen, T D; Heintz, G G; Kaiser, L M et al. (1990) Neuropeptide Y. Differential binding to rat intestinal laterobasal membranes. J Biol Chem 265:6416-22
Nguyen, T D; Kaiser, L M (1990) Vasoactive intestinal peptide receptor on liver plasma membranes: solubilization and cross-linking. Peptides 11:1255-61

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