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Currently available antiarrhythmic drugs for the management of AF are not sufficiently effective and are burdened with cardiac and extracardiac side effects that may offset their therapeutic benefits. Better knowledge about the mechanisms underlying generation and maintenance of AF may lead to the discovery of new targets for pharmacological interventions. These could include atrial-selective ion channels (e.g. atrial I(Na), I(Kur) and I(K,ACh)), pathology-selective ion channels (constitutively active I(K,ACh), TRP channels), ischemia-uncoupled gap junctions, proteins related to malfunctioning intracellular Ca2+ homeostasis (e.g., "leaky" ryanodine receptors, overactive Na+, Ca2+ exchanger) or risk factors for arrhythmias ("upstream" therapies). The review will briefly summarize the current pathophysiological and therapeutic concepts of AF. A description of recently developed antiarrhythmic drugs and their proposed pharmacological action will follow. The final section will speculate about some putative targets for antiarrhythmic drug action in the context of the remodelled atria., (2010 Elsevier Inc. All rights reserved.)

Cannabinoids, including the bioactive constituents of the marijuana plant, their synthetic analogs, and endogenous lipids with cannabinoid-like activity, produce their biological effects by interacting with specific receptors. To date, two G protein-coupled cannabinoid receptors have been identified by molecular cloning, CB1 receptors mainly expressed in the brain and mediating most of the neurobehavioral effects of cannabinoids and CB2 receptors expressed by immune and hematopoietic tissues. Recent findings indicate that some cannabinoid effects are not mediated by either CB1 or CB2 receptors, and in some cases there is compelling evidence to implicate additional receptors in these actions. These include transient receptor potential vanilloid 1 (TRPV1) receptors and as-yet-unidentified receptors implicated in the endothelium-dependent vasodilator effect of certain cannabinoids and in the presynaptic inhibition of glutamatergic neurotransmission in the hippocampus. The case for these additional receptors is being reviewed here.

This review discusses the mechanism(s) of general anesthesia from a pharmacological viewpoint; in particular, the ability of drugs to produce many different effects is emphasised. The problems of experimental measurement of general anesthesia are discussed, and the possibilities for antagonism and potentiation of anesthesia considered. Physicochemical studies on anesthesia are described, as are the advancement of ideas beyond consideration of lipids and proteins as separate sites of action. The importance of studies on different areas of the brain is highlighted, and the review finishes with a survey of the effects of general anesthetics on synaptic transmission which emphasises the problems of extrapolation from in vitro to in vivo.