The hydrogen sulphide-releasing derivative of diclofenac protects against ischaemia-reperfusion injury in the isolated rabbit heart.

BACKGROUND AND PURPOSE: Hydrogen sulphide (H(2)S) is an endogenous gaseous mediator active in the multilevel regulation of pathophysiological functions in mammalian cardiovascular tissues. EXPERIMENTAL APPROACH: This study investigated the pharmacological activity of a new H(2)S-releasing derivative of diclofenac, S-diclofenac (2-[(2,6-dichlorophenyl)amino]benzeneacetic acid 4-(3H-1,2-dithiole-3-thione-5-yl)-phenyl ester) in the isolated rabbit heart submitted to low-flow ischaemia-reperfusion damage. KEY RESULTS: S-diclofenac (3, 10 and 30 microM), despite inhibiting prostacyclin generation by cardiac tissues, achieved dose-dependent normalization of coronary perfusion pressure, reducing left ventricular contracture during ischaemia and improving left ventricular developed pressure and +/-dP/dt(max) at reperfusion. Creatine kinase and lactate dehydrogenase activities in heart perfusates were significantly reduced during reperfusion. These effects were accompanied by substantial release of reduced glutathione (GSH), indicating that the H(2)S moiety may have up-regulated cysteine transport. The anti-ischaemic activities of S-diclofenac and the H(2)S-donor sodium hydro sulphide (NaHS) were partially prevented by the K(ATP) channel antagonist glibenclamide, suggesting a mechanism similar to H(2)S-induced cardioprotection in metabolic ischaemic preconditioning. Perfusion with the nitric oxide (NO) synthase inhibitor N(G)-monomethyl-L-arginine worsened the myocardial ischaemia-reperfusion damage, but this was dose-dependently prevented by S-diclofenac and NaHS, suggesting that the released H(2)S may have overcome NO deficiency. CONCLUSION AND IMPLICATIONS: These data show that S-diclofenac had marked anti-ischaemic activity in ischaemic-reperfused rabbit hearts despite inhibition of prostaglandin generation. Increased GSH formation leading to activation of K(ATP) channels may have contributed to this beneficial effect. The pharmacological profile of S-diclofenac and its anti-inflammatory activity, with diminished gastrointestinal side effects, offer therapeutic applications in cardiovascular disease.

Clinical pharmacology of intraperitoneal cisplatin-based chemotherapy.

The management of intraperitoneal tumors, especially when confined to the peritoneal cavity and/or associated with malignant ascites, requires the use of intraperitoneal (i.p.) cisplatin-based chemotherapy. This therapeutic approach, enabling high concentrations of drug and long duration of tumor tissue exposure, while generating a systemic exposure similar to that obtained with intravenous (i.v.) infusion, significantly improves therapeutic ratio. Nowadays, as feasibility issues are easy to overcome, intraperitoneal chemotherapy provides a safe, effective treatment for the management of peritoneal disease, particularly ovarian carcinoma. In this paper we review pharmacological issues of intraperitoneal cisplatin-based chemotherapy in order to provide a ready to use information collection for clinical practice and ongoing research.