Regeneration Of Vertebrate Sensory Receptor Cells

An international group of leading investigators discuss recent progress of sensory structures in lower and higher vertebrates. Experts in two relevant fields--the cell cycle and mitogenic growth factors--present insightful contributions in the search for precursors and/or stem cells in each sense organ plus the signals which regulate those precursors' differentiation both in normal development and regeneration.

The hagfishes comprise a uniform group of some 60 species inhabiting the cool or deep parts of the oceans of both hemispheres. They are considered the most primitive representatives of the group of craniate chordates, which - apart from the hagfishes that show no traces of verte brae -includes all vertebrate animals. Consequently the hagfishes have played and still playa central role in discussions concerning the evolution of the vertebrates. Although most of the focus on hagfishes may be the result of their being primitive, it should not be forgotten that, at the same time, they are specialized animals with a unique way of life that is interesting in its own right. It is now more than 30 years since a comprehensive treatise on hagfishes was published. The Biology of Myxine, edited by Alf Brodal and Ragnar Fange (Universitetsforlaget, Oslo, 1963), provided a wealth of information on the biology of hagfishes, and over the years remained a major source of information and inspiration to students of hagfishes.

"Who would believe that so small a space could contain the images of all the universe?" Leonardo da Vinci The last years of the 20th century have found the discipline of Developmental Biology returning to its original position at the forefront of biological re search. This progress can be attributed to the burgeoning knowledge base on molecules and gene families, and to the power of the molecular genetic ap proach. Topping the list of organ systems which have provided the most significant advances would have to be the eye. The vertebrate eye was one of the classic embryologic models, used to demonstrate many important prin ciples, including the concepts of inductive tissue interactions first put forth in the early 1900s. Within the last decade of this century, a return to some of the old questions with the new approaches has put eye development back into the limelight. I find this a highly appropriate topic for a book which aims to spark research for the new millennium. We begin with a chapter that discusses the anatomy of eye development, providing the basic reference information for the chapters that follow. A novel aspect of this introduction is the connection made between develop mental strategies and the eye's optical function. What also emerges from this chapter is the number of important eye structures that have barely been touched by the modern developmental biologist. Work on cornea and ante rior chamber development has lagged behind lens and retina.

Degeneration of sensory receptors or of the nerves innervating them leads to a sensory deficit. Various strategies have been tried for promoting regrowth of sensory receptors, particularly in the eye and ear. The latest data from experimental studies in animals are presented in the book including applications of BDNF and CNTF in the eye and epidermal growth factor in the ear.

The main aim of the symposium on the hearing system is to provide a forum in which data, ideas and models from both the physiological and psychoacoustical standpoints can be presented and discussed. Apart from those areas traditionally covered by such meetings, two areas with important recent advances have been included, viz, development and regeneration. The present volume will be of interest to all scientists working in the field of auditory research.

International Review of Cytology V146