The Renin-Angiotensin System

The renin-angiotensin system and the mechanisms regulating this system developed during the adaptive evolution of verte­ brates, along with many other systems involved in the in­ tegrated survival of the organism. Because animal species have evolved from common ancestral populations, a basis for the comparison of body structures and physiological processes ex­ ists among animal groups belonging to different classifications. The comparative approach provides a better understanding of the structure and function of adaptive systems and facilitates the development of general principles governing these systems among animal groups; further, this approach reveals significant characteristics specific to certain animal groups. As the evolu­ tion of adaptation of animals to environmental conditions is explored, directions for future research are suggested. In this book, advances in research on the renin-angiotensin system are described with emphasis on the comparative aspects. However, since studies on the renin-angiotensin system of birds, reptiles, amphibians and fishes are limited compared with those con­ ducted in mammals, in some chapters descriptions are con­ cerned primarily with mammals. It has taken a long time to write this volume, and the topic is a broad one, with new data always emerging; therefore, certain aspects, and sometimes the most recent information, may not be included. Chapters 1-3 and sections 8. 1-8. 4,8. 6, 8. 7 were written by H. K. ; Chapters 4-7 and Section 8. 5 by Y. T. ; Chapter 9 was written by both authors. H. Uemura, M. Nozaki, Y. Okawara, We are indebted to Drs.

Contenu

1 Introduction.- 1.1 Evolutionary Aspects of the Renin-Angiotensin System (RAS).- 1.2 Historical Background of RAS.- 1.3 Survey of Books and Reviews.- 2 Comparative Morphology of the Juxtaglomerular Apparatus (JGA).- 2.1 Mammals.- 2.1.1 Components of JGA.- 2.1.2 Juxtaglomerular (JG) Cells in Afferent Arterioles.- 2.1.2.1 Staining of Granules in JG Cells.- 2.1.2.2 Cellular Localization of Renin.- 2.1.2.3 Electron Microscopy.- 2.1.3 Extraglomerular Mesangium (EGM) and Macula Densa (MD).- 2.1.4 Efferent Arterioles.- 2.1.5 Peripolar Cells.- 2.2 Birds.- 2.3 Reptiles.- 2.4 Amphibians.- 2.5 Fishes.- 2.5.1 JG Cells in Teleosts with Glomerular Kidney.- 2.5.2 JG Cells in Teleosts with Aglomerular Kidney.- 2.5.3 Renin Activity, MD, EGM and Peripolar Cells in Glomerular and Aglomerular Fishes.- 2.5.4 Sarcopterygians and Primitive Bony Fishes.- 2.5.5 Holocephalans.- 2.5.6 Elasmobranchs.- 2.5.7 Cyclostomes.- 2.5.8 Summary.- 3 Innervation in the JGA.- 3.1 Light Microscopy.- 3.2 Electron Microscopy.- 3.3 Summary.- 4 Tissue Distribution of the RAS.- 4.1 Renin.- 4.2 Angiotensinogen.- 4.3 Converting Enzyme.- 4.4 Angiotensins.- 4.5 Nonmammalian Vertebrates.- 5 Regulation of Renin Release.- 5.1 Factors Affecting Renin Release.- 5.1.1 Baroreceptor.- 5.1.2 Macula Densa.- 5.1.3 Renal Nerve.- 5.1.4 Humoral Factors.- 5.1.4.1 Ions.- 5.1.4.2 Amines.- 5.1.4.3 Peptides.- 5.1.4.4 Steroids.- 5.1.4.5 Prostaglandins.- 5.1.4.6 Adenosines.- 5.2 Subcellular Mechanisms.- 5.3 Nonmammalian Vertebrates.- 5.3.1 Birds.- 5.3.2 Reptiles.- 5.3.3 Amphibians.- 5.3.4 Fishes.- 6 Biochemistry of the RAS.- 6.1 Renin.- 6.2 Angiotensinogen.- 6.3 Angiotensin I.- 6.4. Converting Enzyme.- 6.5 Angiotensinases.- 6.6 Nonmammalian Vertebrates.- 6.6.1 Birds.- 6.6.2 Reptiles.- 6.6.3 Amphibians.- 6.6.4 Fishes.- 7 Angiotensin Receptors.- 7.1 Structure of ANG II Receptors.- 7.2 ANG II Receptors in Target Tissues.- 7.2.1 Peripheral Tissues.- 7.2.1.1 Muscular Tissues.- 7.2.1.2 Nonmuscular Tissues.- 7.2.2 Central Nervous System.- 7.3 Signal Transduction of ANG II Receptors.- 7.4 Nonmammalian Vertebrates.- 8 Biological Actions of ANG II.- 8.1 Renal Dipsogen - Historical Background.- 8.2 Exogenous ANG II and Drinking.- 8.2.1 Mammals.- 8.2.2 Birds.- 8.2.3 Reptiles.- 8.2.4 Amphibians.- 8.2.5 Fishes.- 8.2.6 Summary.- 8.3 Endogenous ANG II and Drinking.- 8.3.1 Plasma ANG II and Drinking.- 8.3.2 Drinking and ANG II Antagonists, Renin Inhibitors and Converting Enzyme Inhibitors.- 8.3.3 Brain ANG and Drinking.- 8.3.4 Summary.- 8.4 Sites of Action of ANG II in Drinking.- 8.4.1 Subfornical Organ (SFO).- 8.4.2 Preoptic Area.- 8.4.3 Organum Vasculosum of Lamina Terminalis (OVLT).- 8.4.4 Median Preoptic Nucleus (MnPO).- 8.4.5 Neural Connections Between SFO, OVLT and MnPO.- 8.4.6 Other Possible Receptive Sites for ANG II.- 8.4.7 Nonmammalian Vertebrates.- 8.4.8 Summary.- 8.5 ANG II and Sodium Appetite.- 8.5.1 Mammals.- 8.5.2 Birds.- 8.5.3 Summary.- 8.6 Release of Hormones by ANG II.- 8.6.1 Neurohypophysial Hormones.- 8.6.2 ACTH and CRH.- 8.6.3 Prolactin (PRL).- 8.6.4 GH and TSH.- 8.6.5 LH and LHRH.- 8.6.6 Corticoids.- 8.7 Other Actions of ANG II.- 9 General Conclusions.- 9.1 Comparative Anatomy of the RAS.- 9.1.1 Invertebrates.- 9.1.2 Components of JGA.- 9.1.3 Tissue RAS.- 9.2 Renin Release.- 9.3 Comparative Biochemistry of the RAS.- 9.3.1 Components of the RAS.- 9.3.2 Receptors and Cellular Mechanisms.- 9.4 Biological Actions.- 9.4.1 Body Fluid Regulation.- 9.4.2 Ecological Aspects of ANG II-Induced Drinking.- 9.4.3 ANG II and Reaction to Emergency.- References.