Prolactin-releasing peptide regulates cardiac contractility

Attila Kónyi, Réka Skoumal, Anna Maria Kubin, Gábor Füredi, Ábel Perjés, Klára Farkasfalvi, Zsolt Sárszegi, Ferenc Horkay, Iván G. Horváth, Miklós Tóth, Heikki Ruskoaho, István Szokodi

Research output: Contribution to journalArticle

6 Citations (Scopus)


High levels of specific prolactin-releasing peptide (PrRP) binding sites have been found in the myocardium; however, the functional importance of PrRP in the regulation of cardiac function is unknown. In isolated perfused rat hearts, infusion of PrRP (1-100 nM) induced a dose-dependent positive inotropic effect. Inhibition of cAMP catabolism by IBMX, a phosphodiesterase inhibitor, failed to augment the contractile effect of PrRP. The protein phosphatase (PP1/PP2A) inhibitor calyculin A increased the inotropic response to PrRP, whereas the PP2A inhibitor okadaic acid had no effect. Ro32-0432, a protein kinase Cα (PKCα) inhibitor, significantly enhanced the inotropic effect of PrRP as well as the phosphorylation of phospholamban at Ser-16. In conclusion, the present data define a hitherto unrecognized role for PrRP in the regulation of cardiovascular system by showing that PrRP exerts a direct positive inotropic effect. Moreover, our results suggest that the cAMP-independent inotropic response to PrRP is suppressed by concurrent activation of PKCα and PP1.

Original languageEnglish
Pages (from-to)9-13
Number of pages5
JournalRegulatory Peptides
Issue number1-3
Publication statusPublished - Jan 8 2010



  • Contractile function
  • Prolactin-releasing peptide
  • Protein kinase Cα
  • Protein phosphatase
  • Signal transduction

ASJC Scopus subject areas

  • Biochemistry
  • Physiology
  • Endocrinology
  • Clinical Biochemistry
  • Cellular and Molecular Neuroscience

Cite this

Kónyi, A., Skoumal, R., Kubin, A. M., Füredi, G., Perjés, Á., Farkasfalvi, K., Sárszegi, Z., Horkay, F., Horváth, I. G., Tóth, M., Ruskoaho, H., & Szokodi, I. (2010). Prolactin-releasing peptide regulates cardiac contractility. Regulatory Peptides, 159(1-3), 9-13.