PAF decreases cardiac contractility and blood pressure. To characterize the cardiac PAF receptor, we screened a human ventricular cDNA library in a low stringency condition, using a PCR product derived from guinea pig lung PAF receptor as a probe. Four clones were obtained and named HV1-4. In Xenopus oocytes injected with cRNA derived from HV3 or 4 but not from HV1 or 2, PAF elicited a Ca2+-activated Cl-current. HV3 and HV4 were duplicate clones, encoding a 342 amino-acid polypeptide which was identical to that of the human leukocyte PAF receptor. However, a portion of the 5′ untranslated region of HV3 (or 4) was different from that of the leukocyte receptor cDNA. Northern blotting of human ventricles and atria using the HV3 insert showed a single band of ∼4 kb. These results suggest a tissue-specific translational mechanism responsible for regulation of the expression of the PAF receptor mRNA in these tissues.
|Original language||English (US)|
|Number of pages||8|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Dec 15 1992|
Bibliographical noteFunding Information:
The authors thank Dr. Andre Terzic (Mayo Foundation) for his critical reading of this manuscript and Ms. Elizabeth Erlandson for her technical assistance. This work was supported by NIH ROl HL47360-01 to Y.K. and was done during the tenure of an Established Investigatorship of the American Heart Association to Y. K.