Book contents
- Frontmatter
- Contents
- Preface and acknowledgements
- Part one Reproductive biology
- 1 Fertility and infertility
- 2 Sex determination and gamete maturation
- 3 Neuroendocrine control of puberty
- 4 Control of the menstrual cycle
- 5 The testis and control of spermatogenesis
- 6 Sexual behaviour and pheromones
- 7 Sociobiology and reproductive success
- 8 Fertilization and the initiation of development
- 9 Maternal physiology during gestation and fetal development
- 10 Parturition and lactation: hormonal control
- 11 Parental behaviour and the physiology of the neonate
- 12 Decline in male reproduction and the menopause
- Part two Reproduction and social issues
- Index
5 - The testis and control of spermatogenesis
Published online by Cambridge University Press: 05 June 2012
- Frontmatter
- Contents
- Preface and acknowledgements
- Part one Reproductive biology
- 1 Fertility and infertility
- 2 Sex determination and gamete maturation
- 3 Neuroendocrine control of puberty
- 4 Control of the menstrual cycle
- 5 The testis and control of spermatogenesis
- 6 Sexual behaviour and pheromones
- 7 Sociobiology and reproductive success
- 8 Fertilization and the initiation of development
- 9 Maternal physiology during gestation and fetal development
- 10 Parturition and lactation: hormonal control
- 11 Parental behaviour and the physiology of the neonate
- 12 Decline in male reproduction and the menopause
- Part two Reproduction and social issues
- Index
Summary
Both the following account concerning testicular physiology and the control of spermatogenesis and the preceding chapter concerning the menstrual cycle highlight the numerous common mechanisms in gonadal control of egg and sperm production. It was not until modern molecular biological techniques became available that it was possible to reinterpret the older cytological and endocrine findings and reach a better understanding of the testis as a functional unit. The 1980s was a particularly good decade in the advancement of our knowledge of both ovaries and testes. Numerous studies have focussed on auto-and paracrine factors influencing intra-and extratubular elements and the relationship of the Sertoli cell to the configurational changes which occur in the germ cell during spermatogenesis. Many secretory products of Sertoli cell (morphological equivalent of the granulosa) and Ley dig cell (morphological equivalent of the theca) origin have been identified, including growth factors, cytokines, regulatory peptides, transport proteins and plasminogen activators. The isolation of the differentiating germ cells in a physiologically distinct compartment by means of a Sertoli–Sertoli junctional barrier, vascular restriction and receptor exclusiveness is homologous to the ‘ two-cell-type: two-gonadtrophin’ control of follicular steroidogenesis in oocyte maturation. In a wider context, environmental influences can interrupt the complex process of spermatogenesis with important consequences for male reproduction, as they do for the female. Beyond spermatogenesis, there is also the potential for environmental stresses to affect sperm motility, both before and after ejaculation. In future a deeper understanding of the whole individual, within an environmental context, will be an important area of focus.
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- Chapter
- Information
- A Guide to ReproductionSocial Issues and Human Concerns, pp. 74 - 93Publisher: Cambridge University PressPrint publication year: 1994