Do Diuretics have Antinociceptive Actions: Studies of Spironolactone, Eplerenone, Furosemide and Chlorothiazide, Individually and with Oxycodone and Morphine.
Spironolactone, eplerenone, chlorothiazide and furosemide are diuretics that have been suggested to have antinociceptive properties, for example via mineralocorticoid receptor antagonism. In co-administration, diuretics might enhance the antinociceptive effect of opioids via pharmacodynamic and pharmacokinetic mechanisms. Effects of spironolactone (100 mg/kg, i.p.), eplerenone (100 mg/kg, i.p.), chlorothiazide (50 mg/kg, i.p.) and furosemide (100 mg/kg, i.p.) were studied on acute oxycodone (0.75 mg/kg, s.c.)- and morphine (3 mg/kg, s.c.)-induced antinociception using tail-flick and hot plate tests in male Sprague Dawley rats. The diuretics were administered 30 min. before the opioids, and behavioural tests were performed 30 and 90 min. after the opioids. Concentrations of oxycodone, morphine and their major metabolites in plasma and brain were quantified by mass spectrometry. In the hot plate test at 30 and 90 min., spironolactone significantly enhanced the antinociceptive effect (% of maximum possible effect) of oxycodone from 10% to 78% and from 0% to 50%, respectively, and that of morphine from 12% to 73% and from 4% to 83%, respectively. The brain oxycodone and morphine concentrations were significantly increased at 30 min. (oxycodone, 46%) and at 90 min. (morphine, 190%). We did not detect any independent antinociceptive effects with the diuretics. Eplerenone and chlorothiazide did not enhance the antinociceptive effect of either opioid. The results suggest that spironolactone enhances the antinociceptive effect of both oxycodone and morphine by increasing their concentrations in the central nervous system.
Department of Pharmacology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
Viljami
V
Jokinen
Department of Pharmacology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
Tuomas
T
Lilius
Department of Clinical Pharmacology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
Jouko
J
Laitila
Department of Clinical Pharmacology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.|HUSLAB, Helsinki University Hospital, Helsinki, Finland.
Mikko
M
Niemi
Department of Pharmacology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
Oleg
O
Kambur
Department of Pharmacology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.|Division of Pain Medicine, Department of Anesthesiology, Intensive Care and Pain Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
Eija
E
Kalso
Department of Pharmacology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
Pekka
P
Rauhala
D000700:Analgesics / Q000627:therapeutic use*; D000701:Analgesics, Opioid / Q000097:blood / Q000378:metabolism / Q000493:pharmacokinetics / Q000627:therapeutic use; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002740:Chlorothiazide / Q000627:therapeutic use; D004195:Disease Models, Animal; D004232:Diuretics / Q000627:therapeutic use*; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D000077545:Eplerenone; D005665:Furosemide / Q000627:therapeutic use; D008297:Male; D009020:Morphine / Q000097:blood / Q000378:metabolism / Q000493:pharmacokinetics / Q000627:therapeutic use; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D010098:Oxycodone / Q000097:blood / Q000378:metabolism / Q000493:pharmacokinetics / Q000627:therapeutic use; D010146:Pain / Q000097:blood / Q000378:metabolism / Q000517:prevention & control*; D017207:Rats, Sprague-Dawley; D013148:Spironolactone / Q000031:analogs & derivatives / Q000627:therapeutic use*; D014018:Tissue Distribution
D000700:Analgesics; D000701:Analgesics, Opioid; D004232:Diuretics; D013148:Spironolactone; D000077545:Eplerenone; D009020:Morphine; D002740:Chlorothiazide; D005665:Furosemide; D010098:Oxycodone