After the pioneering studies by Ussing and co-workers, studies of epithelial Nael transport have come a long way. The first phase of the phenomenological description of the cell as a black box has been follow ed by studies of cellular mechanisms, the interplay of the different trans port components, and the mechanisms of regulation. A broad spectrum of methods has been applied to many epithelia in a variety of species. For the individual epithelia transport schemes have been proposed, and, at this point I think it is appropriate to take a pause and search for elements common to several...

In this second special issue on signal transduction leading specialists in their fields again present overviews of topics related to the highly topicalsubject of signal transduction. The first contribution, by Keppler, deals with the biosynthesis, transport, inactivation, and analysis of leukotrienes. Mohr et al. present an excellent overview of the biology of the peptide hormone oxytocin and its role in signal transduction.The review by Holzer describes the significance of peptinergic sensory neurons in the control of vascular functions. In the contribution by Wolf etal the molecular biology...

P.J. Pearson, P.M. Vanhoutte: Vasodilator and Vasoconstrictor Substances Produced by the Endothelium. L. Dux: Muscle Relaxation and Sarcoplasmic Reticulum Function in Different Muscle Types. C.C. Ashley, P.J. Griffith, T.J. Lea, I.P. Mulligan, R.e. Palmer, and S.J. Simnett: Barnacle Muscle: Ca2+ Activation and Mechanics.

R. Levenson: Isoforms of the Na, K-ATPase: Family Members in Search of Function.- E. Petzinger: Transport of Organic Anions in the Liver. An Update on Bile Acid, Fatty Acid, Monocarboxylate, Anionic Amino Acid, Cholephilic Organic Anion and Anionic Drug Transport.- E. Schultz, K.M. McCormick: Skeletal Muscle Satellite Cells.

K.W. Bock: The Aryl Hydrocarbon or Dioxin Receptor: Biologic and Toxic Responses.-
K. Grieshaber, I. Hardewig, U. Kreutzer, and H.-O. Portner: Physiological and Metabolic Responses to Hypoxia in Invertebrates.-
K.-W. Koch: Calcium as Modulator of Phototransduction in Vertebrate Photoreceptor Cells.

In this regular issue of Reviews of Physiology the first contribution by Warth and Bleich is on K+ Channels and Colonic Function, the second by Offermanns on Mammalian G-Protein Function in vivo: New Insights Through Altered Expression, and the third contribution by Tenenholz et al. (including one editor of the series) on Structural Determinants of Scorpion Toxin Affinity: The Charybdotoxin (alpha-KTX) Family of K+-channel Blocking Peptides.

Cook et al.: Phospholipases C and D in Mitogenic Signal Transduction. Moolenaar et al: Lysophosphatidatic Acid: A Bioactive Phospholipid with Growth Factor-Like Properties. Kozma et al.: Serine/Threonine Kinases in thePropagation of the Early Mitogenic Response. Diringer et al: A Retrospective on Transformation, Growth Control, and some Peculiarities of Lipid Metabolism. Villereal et al.: Calcium Signals in Growth Factor Signal Transduction. Wakabayashi et al.: Structure Function of the Growth Factor-Activatable Na+/H+ Exchanger. Herrlich et al.: DNA Damage-Induces Gene Expression: Signal...

J.A. Roth: Membrane-Bound Catechol-O-Methyltreansferase: A Reevaluation of Its Role in the O-Methylation of the Catecholamine Transmitters. D.J. Benos, S. Cunningham, R.R. Baker, K.B. Beason, Y. Oh, and P.R. Smith: Molecular Characteristics of Amiloride-Sensitive Sodium Channels. D. Pette and G. Vrbov : Adaptation of Mammalian Skeletal Muscle Fibers to Chronic Electrical Stimulation.

Springer Book Archives

The four contributions by Ishibashi et al., Klussmann et al., Zeuthen and Larsen et al. summarize the current knowledge on the molecular mechanisms underlying the short and long term regulation of water channels (AQPs) in principal cells, fluid transport by leaky epithelia and cotransporters of the symport type which behave as molecular water pumps.