ADP‐induced bladder contractility is mediated by P2Y12 receptor and temporally regulated by ectonucleotidases and adenosine signaling. Issue 12 (10th September 2014)

• Record Type: Journal Article
• Authors: Yu, Weiqun; Sun, Xiaofeng; Robson, Simon C.; Hill, Warren G.
• Is Part Of: FASEB journal. Volume 28:Issue 12(2014)
• Page Start: 5288
• Page End: 5298
• Publication Date: 2014-09-10
• Subjects: detrusor -- urinary tract -- myography -- micturition -- mechanotransduction; Biology -- Periodicals; Biology, Experimental -- Periodicals; 570
• DOI: 10.1096/fj.14-255885
• Languages: English
• ISSNs: 0892-6638

Abstract

Abstract : Purinergic signaling comprises one key pathway in modulating bladder smooth muscle (BSM) contractility, disorders of which become highly prevalent with aging. ADP was first observed to modulate BSM contractility >40 yr ago, yet the underlying molecular mechanism still remains unclear. Here, we demonstrate, using myography, that ADP and ADPβS dose‐dependently induce mouse BSM contraction, and ADP‐induced BSM contraction is blocked by a selective P2Y12 receptor (P2Y12 R) antagonist, PSB 0739 (25 μM), but is unaffected by P2Y1 and P2Y13 receptor antagonists. P2Y12 R in BSM exhibits distinct pharmacological properties that are different from P2Y12 R in platelets. After an immediate contraction, prolonged exposure to ADP causes BSM to become refractory to further ADP‐mediated contraction. However, in mice lacking ectonucleotidases Entpd1 (ATP→ADP→AMP) or Nt5e (AMP→adenosine), or by inhibiting adenosine signaling, the refractory response was altered, resulting in repeated BSM contractions in response to repeated ADP (0.1‐1 mM) stimulation. Our data indicate that P2Y12 R undergoes slow desensitization; ADP‐P2Y12 signaling is tightly regulated by Entpd1/Nt5e activity and adenosine receptors; and ADP‐adenosine signaling play an important role in modulating P2X‐mediated BSM contraction. The identification of P2Y12 R in BSM, and the current clinical availability of P2Y12 R inhibitors, such as clopidogrel, offers potentially novel treatment strategies for bladder contractility disorders.—Yu, W., Sun, X., Robson, S. C., Hill, W. G., ADP‐induced bladder contractility is mediated by P2Y12 receptor and temporally regulated by ectonucleotidases and adenosine signaling. FASEB J. 28, 5288–5298 (2014). www.fasebj.org