Interaction of thymic peptide thymosin alpha 1 with VIP receptors in rat intestinal epithelial cells: comparison with PHI and secretin.
1. Thymic peptide thymosin alpha 1 (10(-10)-10(-7) M) is shown to inhibit the specific binding of 125I-labelled VIP. 2. Thymosin alpha 1 was 1500 times less potent than VIP at inhibiting 125I-labelled VIP binding. 3. Thymosin alpha 1 (10(-10)-10(-7) M) was weak in stimulating cyclic AMP production. 4. Interaction of thymosin alpha 1 with VIP receptors is compared with PHI and secretin. 5. The order of affinity of different peptides is VIP greater than PHI greater than secretin greater than thymosin alpha 1.
Calvo
J R
JR
Departamento de Bioquimica Médica y Biología Molecular, Facultad de Medicina, Sevilla, Spain.
Guerrero
J M
JM
Goberna
R
R
D000818:Animals; D002417:Cattle; D000242:Cyclic AMP / Q000096:biosynthesis; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D006728:Hormones / Q000378:metabolism; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000378:metabolism; D007457:Iodine Radioisotopes; D010451:Peptide PHI / Q000494:pharmacology*; D051381:Rats; D011964:Receptors, Gastrointestinal Hormone / Q000378:metabolism*; D018005:Receptors, Vasoactive Intestinal Peptide; D012633:Secretin / Q000494:pharmacology*; D013552:Swine; D000077596:Thymalfasin; D013947:Thymosin / Q000031:analogs & derivatives* / Q000494:pharmacology; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism
D006728:Hormones; D007457:Iodine Radioisotopes; D010451:Peptide PHI; D011964:Receptors, Gastrointestinal Hormone; D018005:Receptors, Vasoactive Intestinal Peptide; D012633:Secretin; D014660:Vasoactive Intestinal Peptide; D013947:Thymosin; D000242:Cyclic AMP; D000077596:Thymalfasin