Synopses & Reviews
The Third International Symposium on Lipid Metabolism in the Normoxic and Ischemic Heart was held in Rotterdam, the Netherlands, September 9-10, 1991. The topics of this meeting were focused on: 1. Modulation of myocardial lipid metabolism, 2. Biological membranes; structure, functiona and turnover, 3. Pharmacological modification of myocardial fatty acid oxidation, 4. Myocardial vascular endothelium; contribution to myocardial lipid homeostasis. Special attention is given to the interrelationship between carbohydrates and fatty acids as energy substrates for the heart under normoxic and (post) ischemic circumstances, the influence of diets, varying in their fatty acid composition, on cardiac function, and the significance of phospholipid topology, turnover, and methylation in general and the phosphatidylinositol pathway in particular on performance of the heart. The role of carnitine in cardiac function altered by lack of oxygen or by elevated levels of fatty acyl derivatives of carnitine and the modulatory effects of the endothelium on cardiac lipid homeostasis were also extensively discussed during the conference. This focused Issue of Molecular and Cellular Biochemistry is a collection of invited papers based on the lectures and a selection of posters presented during the meeting. It includes contributions of renowned investigators delineating recent results and discussing significant aspects of their data in an attempt to enlarge our insight in the complexity of cardiac lipid transport and metabolism, in the healthy and diseased myocardium.
Synopsis
The discovery of the second-messenger functions of on serine and threonine residues. Although there is inositol 1,4,5-trisphosphate (Ins(1,4,5)P 3) and 1,2-dia- general agreement that PKC plays an important role in cylglycerol (DAG), the products of receptor-stimulated the initiation and/or modulation of receptor-linked re- phosphatidylinositol 4,5-bisphosphate (PtdIns( 4,5)P ) 2 sponses, the precise nature or molecular details of this hydrolysis, marked a turning point in the studies on the involvement remain elusive. There are several sugges- mechanisms of mediation of functional hormone and tions of possible functions of PKC, including involve- neurotransmitter responses. The historical background ment in modulation of ionconductance, regulation of of this discovery and the extensive bibliography of the receptor interaction with components of (other) signal 2 enormously expanding knowledge in this field was re- transduction pathways, modulation of Ca + sensitivity cently presented by Rana and Hokin 1], the latter of contractile proteins and gene expression 6]. author who first observed the 'phosphoinositide' effect The receptors involved in the activation of the adeny- 35 years ago. It was, however, the Ca2+ gating hypothe- late cyclase and PtdIns cascade pathways have one com- sis proposed by Michell 2] on basis of a survey of mon feature. They are present in the plasmamembrane observations on the phosphoinositide turnover in a as complexes with GTP binding proteins (G-proteins).