Diverse regulation of IP3 and ryanodine receptors by pentazocine through σ1-receptor in cardiomyocytes.
Although pentazocine binds to σ1-receptor (σ1R) with high affinity, the physiological relevance of its binding remains unclear. We first confirmed that σ1R stimulation with pentazocine rescues contractile dysfunction following pressure overload (PO)-induced cardiac hypertrophy ovariectomized (OVX) female rats. In in vivo studies, vehicle, pentazocine (0.5-1.0 mg/kg ip), and NE-100 (1.0 mg/kg po), a σ1R antagonist, were administered for 4 wk (once daily) starting from the onset of aortic banding after OVX. We also examined antihypertrophic effects of pentazocine (0.5-1 μM) in cultured cardiomyocytes exposed to angiotensin II. Pentazocine administration significantly inhibited PO-induced cardiac hypertrophy and rescued hypertrophy-induced impairment of cardiac dysfunctions such as left ventricular end-diastolic pressure, left ventricular developed pressure, and left ventricular contraction and relaxation (±dp/dt) rates. Coadministration of NE-100 with pentazocine eliminated pentazocine-induced amelioration of heart dysfunction. Interestingly, pentazocine administration inhibited PO-induced σ1R reduction and inositol-1,4,5-trisphosphate (IP3) receptor type 2 (IP3R2) upregulation in heart. Therefore, the reduced mitochondrial ATP production following PO was restored by pentazocine administration. Furthermore, we found that σ1R binds to the ryanodine receptor (RyR) in addition to IP3 receptor (IP3R) in cardiomyocytes. The σ1R/RyR complexes were decreased following OVX-PO and restored by pentazocine administration. We noticed that pentazocine inhibits the ryanodine-induced Ca(2+) release from sarcoplasmic reticulum (SR) in cultured cardiomyocytes. Taken together, the stimulation of σ1R by pentazocine rescues cardiac dysfunction by restoring IP3R-mediated mitochondrial ATP production and by suppressing RyR-mediated Ca(2+) leak from SR in cardiomyocytes.
Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan;
Hideaki
H
Tagashira
Md Shenuarin
MS
Bhuiyan
Kohji
K
Fukunaga
D000255:Adenosine Triphosphate / Q000096:biosynthesis; D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D000840:Anisoles / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D006332:Cardiomegaly / Q000378:metabolism / Q000503:physiopathology; D002478:Cells, Cultured; D005260:Female; D006321:Heart / Q000187:drug effects; D017379:Hypertrophy, Left Ventricular / Q000378:metabolism / Q000503:physiopathology; D053496:Inositol 1,4,5-Trisphosphate Receptors / Q000187:drug effects* / Q000378:metabolism; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D009200:Myocardial Contraction / Q000187:drug effects; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000378:metabolism; D009292:Narcotic Antagonists / Q000494:pharmacology; D009294:Narcotics / Q000494:pharmacology*; D010052:Ovariectomy; D010423:Pentazocine / Q000494:pharmacology*; D011437:Propylamines / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D017480:Receptors, sigma / Q000819:agonists* / Q000037:antagonists & inhibitors; D019837:Ryanodine Receptor Calcium Release Channel / Q000187:drug effects* / Q000378:metabolism; D012519:Sarcoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D000097605:Sigma-1 Receptor
D000255:Adenosine Triphosphate; D000804:Angiotensin II; D000840:Anisoles; D002118:Calcium; D053496:Inositol 1,4,5-Trisphosphate Receptors; D009292:Narcotic Antagonists; D009294:Narcotics; D010423:Pentazocine; D011437:Propylamines; D017480:Receptors, sigma; D019837:Ryanodine Receptor Calcium Release Channel; D014662:Vasoconstrictor Agents; D000097605:Sigma-1 Receptor; C580990:Ip3r2 protein, mouse; C083832:N,N-dipropyl-2-(4-methoxy-3-(2-phenylethoxy)phenyl)ethylamine monohydrochloride
ATP; inositol-1,4,5-trisphosphate receptor; myocardial hypertrophy; pentazocine; ryanodine receptor; σ1 receptor