Fluvastatin, an HMG-CoA reductase inhibitor, facilitate adenosine production in the rat hearts via activation of ecto-5'-nucleotidase.
The present study was examined whether fluvastatin, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, can increase the production of interstitial adenosine via activation of ecto-5'-nucleotidase in the ventricular myocardium, with use of microdialysis techniques in in situ rat hearts.



Adenosine in the dialysate collected during perfusion with Tyrode's solution containing 100μM AMP (through the probe) originated from the hydrolysis of AMP catalyzed by endogenous ecto-5'-nucleotidase, so that the level of adenosine reflected the activity of ecto-5'-nucleotidase in this tissue.



Fluvastatin (100μM), an inhibitor of low-density lipoprotein (LDL) oxidation, significantly increased the concentration of adenosine measured in the presence of 100μM AMP (i.e., the activity of ecto-5'-nucleotidase) by 154.7±16.0% (n=6, P<0.05), an increase which inhibited an antagonist of the α1-adrenoceptor (prazosin, 50μM) or of protein kinase C (PKC; chelerythrine, 10μM). Fluvastatin (10-500μM) increased the level of AMP-primed dialysate adenosine in a concentration-dependent manner.



These results indicate that fluvastatin increases in adenosine concentrations in the dialysate which resulted from activation of PKC, mediated by stimulation of α1-adrenoceptors, through activation of ecto-5'-nucleotidase.
School of Nursing, Faculty of Health Sciences, Osaka Aoyama University, 2-11-1 Niina, Mino, City, Japan. Electronic address: t-obata@osaka-aoyama.ac.jp.
Toshio
T
Obata
Department of Nursing, School of Health Sciences, Asahi University, 1851 Hozumi Mizuho City Gifu, Japan.
Michiko
M
Nakashima
D015720:5'-Nucleotidase / Q000378:metabolism*; D000241:Adenosine / Q000378:metabolism*; D000249:Adenosine Monophosphate / Q000378:metabolism; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D020536:Enzyme Activators / Q000494:pharmacology*; D005229:Fatty Acids, Monounsaturated / Q000494:pharmacology*; D000077340:Fluvastatin; D058851:GPI-Linked Proteins / Q000378:metabolism; D006352:Heart Ventricles / Q000187:drug effects* / Q000201:enzymology; D006868:Hydrolysis; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D007211:Indoles / Q000494:pharmacology*; D008297:Male; D017551:Microdialysis; D011493:Protein Kinase C / Q000378:metabolism; D017208:Rats, Wistar; D018340:Receptors, Adrenergic, alpha-1 / Q000378:metabolism; D015398:Signal Transduction; D013997:Time Factors
C547715:Adra1a protein, rat; D020536:Enzyme Activators; D005229:Fatty Acids, Monounsaturated; D058851:GPI-Linked Proteins; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D007211:Indoles; D018340:Receptors, Adrenergic, alpha-1; D000249:Adenosine Monophosphate; D000077340:Fluvastatin; D011493:Protein Kinase C; D015720:5'-Nucleotidase; C548243:Nt5e protein, rat; D000241:Adenosine
3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA); Adenosine; Ecto-5′-nucleotidase; Fluvastatin; Low-density lipoprotein (LDL); Protein kinase C (PKC)