The P2Y purinergic receptor expressed by enteric neurones in guinea-pig intestine.
Electrophysiological recording methods provided evidence for presynaptic release of ATP from enteric neurones and postganglionic sympathetic fibres in the enteric nervous system (ENS) of guinea-pig intestine (J Physiol Lond 2003; 550: 493-504). The released ATP acted at postsynaptic P2Y(1) receptors to evoke slow synaptic excitation in neurones in the submucosal division of the ENS. Here, we report the cloning and characterization of the P2Y(1) receptor, which was found in the guinea-pig submucosal layer. A 1178 bp cDNA clone was isolated from guinea-pig submucosal RNA by reverse transcription polymerase chain reaction (RT-PCR). The cDNA contained an open-reading frame of 1119 bp, encoding a 373 amino acid polypeptide of the same length and with 95% identity to the human P2Y(1) receptor. Stable expression of the guinea-pig cDNA in human embryonic kidney (HEK)293 cells was accompanied by a marked increase in sensitivity for elevation of free intracellular calcium evoked by ATP or related nucleotides. The potency order for ATP and its analogues was: 2-methio-adenosine diphosphate > 2-methio-adenosine triphosphate > ADP > ATP-gamma-S > ATP. The selective P2Y(1) receptor antagonist, MRS2179, was a competitive antagonist for the receptor with a pA(2) value of 6.5. The results add to existing evidence for expression of a functional P2Y(1) purinergic receptor in neurones of the submucosal division of the ENS.
Gao
N
N
Department of Physiology and Cell Biology, The Ohio State University, Columbus, 43210, USA.
Hu
H-Z
HZ
Zhu
M X
MX
Fang
X
X
Liu
S
S
Gao
C
C
Wood
J D
JD
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D006168:Guinea Pigs; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D008297:Male; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism*; D018048:Receptors, Purinergic P2 / Q000096:biosynthesis* / Q000235:genetics*; D058472:Receptors, Purinergic P2Y1; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013368:Submucous Plexus / Q000378:metabolism*
D018076:DNA, Complementary; C546382:P2RY1 protein, human; D018048:Receptors, Purinergic P2; D058472:Receptors, Purinergic P2Y1