Preface

The compiling of this book was taken up to create a reference book for readers

interested in mammalian endocrinology and male reproductive biology. This disci-

pline has witnessed considerable progress over the past several years. Keeping this

in view, an attempt has been made to provide up-to-date information on the recent

developments in this field. Unlike a book written by a single author, this book is

the result of a multiauthor effort and provides comprehensive systematic coverage

of topics in mammalian endocrinology and male reproductive biology.

There are 12 chapters in this book. Chapter 1 reviews the evidence for sexual

dimorphism in the central nervous system and considers the mechanisms by which

this is brought about. Chapter 2 on mammalian gonadotropin-releasing hormone

(GnRH) presents an account of its structure, control of release and potential func-

tions. Chapter 3 on gonadotropins – past, present and future – provides a coherent

view of gonadotropins of pituitary origin and their role in the regulation of gonadal

functions. In this chapter, selected topics concerning pituitary protein hormones

and their influence on gonadal processes are discussed, and these include their

purification, structural highlights, microheterogeneity, in vivo and in vitro bioassay,

regulation of biosynthesis and secretion, their receptors in gonadal tissue, and clini-

cal usage. Chapter 4 presents an account of endocrine regulation of spermatogen-

esis. This chapter illustrates how hormones of the hypothalamo–pituitary–gonadal

axis regulate the process of spermatogenesis. Chapter 5 discusses the role of apop-

tosis in spermatogenesis and highlights the signal transduction pathways involved

in apoptosis of germ cells in the testis. Chapter 6 provides a detailed account of

structure and function of the epididymis, which plays a major role in physiologi-

cal maturation of spermatozoa, and this maturation process is a prerequisite for

the sperm to acquire the ability to be motile and to fertilise the oocyte. Chapter

7 deals with regulation of growth and function of epididymides. Hormones such

as follicle-stimulating hormone (FSH), androgen and oestrogen are known to play

role in regulation of epididymal growth and function, so their role in this regula-

tion is discussed. Chapter 8 describes sperm forward motility initiating and regu-

lating molecules located on surface of sperm cell in the epididymis. The authors

have focussed on the sperm cell surface molecules with special reference to external

domain. In Chapter 9, structure and function of the male accessory sex glands are

described. The major male accessory sex glands are the seminal vesicles, prostate

glands and Cowper’s glands, and this chapter provides details of their structure

and function, with associated pathologies. Chapter 10 focuses on recent advances

in male contraception along with a resume of the male reproductive processes and

male reproductive endocrinology, which form the basis for the development of

male-based contraceptive regimens. Chapter 11 describes molecular mechanism

of androgen action. In this article, the author has reviewed current progress in

understanding the molecular mechanism of androgen action with emphasis on

coregulators and their role in physiology and pathology, particularly with a focus

on the brain. Finally, Chapter 12 deals with genomics of male infertility. It is well

to remember that infertility due to male factor contributes approximately 50% of

the infertility cases in humans. A number of autosomal as well as sex chromosomal

genes have been identified that are believed to play a pivotal role in the production

of viable, normal and functional sperm. In this chapter, the authors discuss diverse

aspects of male infertility and the role of genome.

There are inevitably some overlaps, but these are essential for flow and clarity

of the subject matter, and efforts have been made to restrict these to the minimum.

The chapters have been written by authors who are acknowledged leaders in their

respective fields. I wish to express my personal gratitude to all of them for their

valuable contribution and overwhelming support and encouragement. This book

could not have been completed without their fullest cooperation. My thanks are

also due to my research students for their help, and I wish to record my special

appreciation to Ms. Deepanshu Joshi for her invaluable help in many ways. I will

be failing in my duty if I do not acknowledge my wife for the sustained support in

her own way.

Thanks are also due to colleagues at CRC Press/Taylor & Francis, especially to

Dr. Chuck Crumly, Hayley Ruggieri and Amanda Parida for their efforts in ensur-

ing the successful publication of this book.

Finally, I accomplished this task with the Holy Blessings of my Gurumaa and

Gurudev. I hope this book will be useful to all those interested in the area of mam-

malian endocrinology and male reproductive biology be they students, teachers or

researchers.