CHARACTERIZATION OF THE VIP RECEPTOR FROM SUP T1 LYMPHOBLASTS

The SUP T1 lymphoblasts express an original subtype of VIP receptors c haracterized by a high affinity for the VIP analogue from lizard venom named helodermin, a preference for the neuropeptide PACAP-38 over PAC AP-27 and VIP, and an extremely low affinity for secretin. The molecul ar cloning of that receptor revealed its identity with the VIP2 recept or subtype first cloned in rat and mouse tissues. The access to select ive probes permits the detection of the mRNA coding for the VIP, recep tor by Northern blot, reverse transcriptase-polymerase chain reaction (RT-PCR) and in situ hybridization. These highly selective and sensiti ve techniques identify the cell types that are equipped to synthesize the receptor but do not prove that the receptor is indeed efficiently expressed at the cell surface. VIP, mRNA was detected in selected area s of the brain different from that expressing the classical VIP, recep tor, in pituitary, in pineal, in pancreatic islets, in testes and ovar y. It was also detected in the stomach, in the thymus and in spleen an d in T lymphoblastic cell lines. A systematic screening of the immunoc ompetent cells must still be performed. Copyright (C) 1996 Elsevier Sc ience Ltd