This book elucidates the mechanisms involved in biological membrane functions. It describes the new modalities and characterization for basic in vitro as well as computer models of biological membranes. Biological membranes are analyzed in terms of advances in molecular dynamics. The individual chapters provide an in depth analysis of images from various biological models. The potential of membrane models in the context of treatment trials is discussed. The authors present new insights and current concepts for treatment procedures (nanocarriers, electroporation, channel blockers).
Transport and Diffusion across Cell Membranes is a comprehensive treatment of the transport and diffusion of molecules and ions across cell membranes. This book shows that the same kinetic equations (with appropriate modification) can describe all the specialized membrane transport systems: the pores, the carriers, and the two classes of pumps. The kinetic formalism is developed step by step and the features that make a system effective in carrying out its biological role are highlighted. This book is organized into six chapters and begins with an introduction to the structure and dynamics of cell membranes, followed by a discussion on how the membrane acts as a barrier to the transmembrane diffusion of molecules and ions. The following chapters focus on the role of the membrane's protein components in facilitating transmembrane diffusion of specific molecules and ions, measurements of diffusion through pores and the kinetics of diffusion, and the structure of such pores and their biological regulation. This book methodically introduces the reader to the carriers of cell membranes, the kinetics of facilitated diffusion, and cotransport systems. The primary active transport systems are considered, emphasizing the pumping of an ion (sodium, potassium, calcium, or proton) against its electrochemical gradient during the coupled progress of a chemical reaction while a conformational change of the pump enzyme takes place. This book is of interest to advanced undergraduate students, as well as to graduate students and researchers in biochemistry, physiology, pharmacology, and biophysics.
This second Volume in the series on Membrane Transport in Biology contains a group of essays on transport across single biological membranes separating the inside and outside of cells or organelles. We have not attempted to include material on all types of plasma and intracellular membranes, but rather have emphasized structures which have been studied relatively thoroughly. Four chapters describe transport of different types of molecules and ions across the plasma membranes of mammalian red cells. Two essays concern the excitable membranes of nerve and muscle cells while the remaining four chapters treat transport across several types of intracellular membranes. Water makes up more than two-thirds of the mass of most living cells. The transport of water between the inside and outside of cells and organelles is important for the function of these structures. As a result of investigations in many laboratories over the past four decades, our picture of the water permea bility of the red cell membranes is rather detailed when compared to the water permeability of other biological membranes. In Chapter 1, R. I. Macey describes this picture and also considers the permeability of red cell membranes to non electrolytes, including metabolic substrates such as sugars, amino acids, purines and nucleosides.
This second Volume in the series on Membrane Transport in Biology contains a group of essays on transport across single biological membranes separating the inside and outside of cells or organelles. We have not attempted to include material on all types of plasma and intracellular membranes, but rather have emphasized structures which have been studied relatively thoroughly. Four chapters describe transport of different types of molecules and ions across the plasma membranes of mammalian red cells. Two essays concern the excitable membranes of nerve and muscle cells while the remaining four chapters treat transport across several types of intracellular membranes. Water makes up more than two-thirds of the mass of most living cells. The transport of water between the inside and outside of cells and organelles is important for the function of these structures. As a result of investigations in many laboratories over the past four decades, our picture of the water permea bility of the red cell membranes is rather detailed when compared to the water permeability of other biological membranes. In Chapter 1, R. I. Macey describes this picture and also considers the permeability of red cell membranes to non electrolytes, including metabolic substrates such as sugars, amino acids, purines and nucleosides.
An introduction to the principles of membrane transport: How molecules and ions move across the cell membrane by simple diffusion and by making use of specialized membrane components (channels, carriers, and pumps). The text emphasizes the quantitative aspects of such movement and its interpretation in terms of transport kinetics. Molecular studies of channels, carriers, and pumps are described in detail as well as structural principles and the fundamental similarities between the various transporters and their evolutionary interrelationships. The regulation of transporters and their role in health and disease are also considered. - Provides an introduction to the properties of transport proteins: channels, carriers, and pumps - Presents up-to-date information on the structure of transport proteins and on their function and regulation - Includes introductions to transport kinetics and to the cloning of genes that code transport proteins - Furnishes a link between the experimental basis of the subject and theoretical model building
International Review of Cytology presents current advances and comprehensive reviews in cell biology--both plant and animal. Authored by some of the foremost scientists in the field, each volume provides up-to-date information and directions for future research. This volume looks at water movements from a wide range of levels. It examines how water interacts with the major components of the cell, including proteins and lipids. It discusses how water moves across cell membranes by diffusion, how it is chanelled across these membranes or, in certain cases, pumped across, and how water movements are controlled. This book demonstrates how water and ion movements are closely linked in order to provide a better understanding of their behavior. *Essential Physical chemistry of water at biological interfaces *Up-to-date reviews of water behavior in cells *Water in integrated systems *Current information on water channels across membranes
The contributions of this volume are concerned with transport phenomena in multimembrane systems and in simple epithelia. In addition to the very substan tial progress that has been made in the area of transport of fluid and solutes across artifical model membranes in vitro and across simple symmetrical cell membranes, much has been learned from studies of transport phenomena in multi membrane systems of higher complexity to be reviewed in this volume. It should be recalled that many of the fundamental conceptual and methodological problems of transport physiology have been successfully approached and defin ed by studying simple epithelia in vitro, and that the direction that research has taken has been affected in a major way by the cellular transport models that have evolved from this approach. Since then striking progress has been made in several areas. Not only have we been witnessing a keen and productive interest in the realtionship between fine structure and transport behavior in multimem brane systems but significant advancements have also been made in defining individual active and passive transport operations, in analysing cell ion activities and transport pools, and in describing the differences in transport functions that underly the membrane asymmetry and cell polarization of cells subserving di rectional transport.
This Volume forms the cornerstone of this series of four books on Membrane Transport in Biology. It includes chapters that address i) the theoretical basis of investigations of transport processes across biological membranes, ii) some of the experimental operations often used by scientists in this field, iii) chemical and biological properties common to most biological membranes, and iv) planar thin lipid bilayers as models for biological membranes. The themes developed in these chapters recur frequently throughout the entire series. Transport of molecules across biological membranes is a special case of diffu sion and convection in liquids. The conceptual frame of reference used by investigators in this field derives, in large part, from theories of such processes in homogeneous phases. Examples of the application of such theories to transport across biological membranes are found in Chapters 2 and 4 of this Volume. In Chapter 2, Sten-Knudsen emphasizes a statistical and molecular approach while, in Chapter 4 Sauer makes heavy use of the thermodynamics of irreversi ble processes. Taken together, these contributions introduce the reader to the two sets of ideas which have dominated the thinking of scientists working in this field. Theoretical consideration of a more special character are also included in several other Chapters in Volume I. For example, Ussing (Chapter 3) re-works the flux ratio equation which he introduced into the field of transport across biological membranes in 1949.
Ion Transport Across Membranes focuses on the process of ion transport across cell membranes, including ion permeability, biological membranes, and thermodynamics. The selection first offers information on ion transport across biological membranes and electrical processes in nerve conduction. Topics include diffusion through biological membranes, active transport, voltage-current relations in the membrane, myelinated nerve fibers, and sequence of events in a nerve impulse. The text then ponders on generation of bioelectric potentials and optical observations on the interaction between acetyl cholinesterase and its substrate. The publication takes a look at ion permeability of the red cell and renal mechanisms of electrolyte transport. The text also tackles membrane permeability and electrical potential; transport of ions through biological membranes from the standpoint of irreversible thermodynamics; and electrochemical studies with model membranes. Topics include membranes of high electrochemical activity in physicochemical and model studies of biological interest and membrane resting potential. The selection is a vital reference for readers interested in ion transport across membranes.
