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Fertilisation mechanisms in man and mammals
Animal Reproduction Science, 1 (1978/1979) 251--253
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© Elsevier S c i e n t i f i c Publishing C o m p a n y , A m s t e r d a m - - Printed in The N e t h e r l a n d s
Book Reviews F E R T I L I S A T I O N STUDIES
Fertilisation Mechanisms in Man and Mammals. Ralph B.L. Gwatkin. Plenum Press, New York, N.Y., London, 1977, 161 pp., US$ 21.00, ISBN 0-306-31009-0.
During the past t w e n t y years or so, studies of mammalian fertilisation have progressed from essentially the morphological to the molecular level. Instead of the customary descriptions of sperm attachment, penetration, egg activation and pronuclear formation derived from phase-contrast or electron microscopy, more recent experiments have frequently used in vitro fertilisation techniques, for example, to examine binding sites on the zona pellucida, to probe the nature of the egg surface (plasmalemma), and to note critical stages of synthetic activity in the egg cytoplasm. Dr. Gwatkin has certainly been closely associated with many of these new developments, and it comes as no surprise that he should have directed his energies to the production of a monograph. As is readily admitted in the preface, the b o o k derives from an earlier review on the subject of cell surface interactions in fertilisation. Accordingly, two of the questions that must be asked are to what extent this lengthier treatment maintains the excellent standard of the review, and whether the b o o k form is indeed justified by the inclusion of new and critically presented information. The title itself is somewhat misleading for, the erroneous distinction between man and mammals apart, few results are presented that relate purely to fertilisation in man. This is regrettable but stems, of course, from a lack of rigorous information. An overall impression of the 15 chapters is one of variable quality and length, and the sequence of presentation is not altogether logical. Chapters 1 and 13, dealing respectively with historical aspects of the subject and metabolic changes at fertilisation, do n o t exceed two and a half printed pages whilst Chapter 14, dealing with the fate of the millions of spermatozoa deposited in the female tract, amounts to no more than a single side. In Chapters 2 and 3, dealing with eggs and spermatozoa, the formation and maturation of the gametes is treated quite superficially whereas discussion of the nature of their membranes -- if not the individual organelles -- is crisp and authoritative. Chapter 4 surveys gamete transport in the female in three and a half sides plus two tables: several recent findings are highlighted, such as the critical rSle of cilia rather than musculature in promoting egg transport in the ampulla, b u t the fertilisable life of eggs presented in Table 1 is n o t a very meaningful figure without further explanation. Does this represent the potential to undergo sperm penetration and pronuclear formation, or does it refer to the lifespan during which penetration will subsequently give rise to a viable e m b r y o ? The principal site of insemination (i.e., semen deposition) listed in Table 2 needs to be corrected for the
252
pig and dog, in both of which species the bulk of the ejaculate enters the uterus, n o t the vagina. A valuable discussion of in vitro fertilisation is presented in Chapter 5, with useful details of a system for gametes of the golden hamster, but w h y should this appear before chapters dealing with sperm capacitation, the acrosome reaction, and the ensuing events of sperm attachment, penetration and fusion? In fairness to the author, perhaps because techniques of in vitro fertilisation have enabled processes such as capacitation and membrane vesiculation of spermatozoa to be analysed, b u t this is scarcely adequate justification for putting the cart before the horse. The precise character of sperm surface changes in the female tract is still to be resolved, but this reviewer does n o t like the notion that full capacitation occurs in the uterus of mammals. It seems more probable that the uterus and oviducts act synergistically to facilitate this change which, from the point of view of the e c o n o m y of acrosomal enzymes and sperm energy reserves, would more logically be completed in the vicinity of the eggs. Reasoning in the same vein, the acrosome reaction might best be stimulated by components emanating from or remaining in association with the zona pellucida. And, again in contrast to Gwatkin's viewpoint, recent studies suggest that much of the sperm hyaluronidase can be liberated before the acrosome reaction is conspicuous. Mechanisms for binding spermatozoa to the zona pellucida, and those underlying prevention or manipulation of polyspermy, represent active interests of Gwatkin's group, this being well conveyed in the detailed and enthusiastic flavour of these chapters. The final chapters dealing respectively with parthenogenesis and unanswered problems related to fertilisation are also timely, and the bibliography is comprehensive and an invaluable feature of the book. Criticisms of a general nature concern the quality of the photographs which would have been better printed on glossy paper, and the scant attention paid to p r o o f reading: many typographical errors remain, with one particular howler on p. 14 where the dry weight of a bull spermatozoon is presented as 16.5 × 1012g -- clearly n o t a haploid cell! Nevertheless, because the b o o k is well-written and concise, stimulating in terms of emphasizing current areas of gamete research in mammals, and none t o o expensive by modern standards, its publication is welcome and it surely deserves to join the shelves of research institutes and university departments. R.H.F. H U N T E R
(Edinburgh, Great Britain)
NEW TEXT ON UTERINE PHYSIOLOGY
Biology of the Uterus. 2nd Edition of Cellular Biology of the Uterus (ed. in 1967}. R.W. Wynn (Editor). Plenum Press, New York, N.Y., 1977, 748 pp., tables, figures, plates and references. "Biology of the Uterus", edited by R.W. Wynn in 1977, is a new version of "Cellular Biology of the Uterus" published ten years ago. According to
251
© Elsevier S c i e n t i f i c Publishing C o m p a n y , A m s t e r d a m - - Printed in The N e t h e r l a n d s
Book Reviews F E R T I L I S A T I O N STUDIES
Fertilisation Mechanisms in Man and Mammals. Ralph B.L. Gwatkin. Plenum Press, New York, N.Y., London, 1977, 161 pp., US$ 21.00, ISBN 0-306-31009-0.
During the past t w e n t y years or so, studies of mammalian fertilisation have progressed from essentially the morphological to the molecular level. Instead of the customary descriptions of sperm attachment, penetration, egg activation and pronuclear formation derived from phase-contrast or electron microscopy, more recent experiments have frequently used in vitro fertilisation techniques, for example, to examine binding sites on the zona pellucida, to probe the nature of the egg surface (plasmalemma), and to note critical stages of synthetic activity in the egg cytoplasm. Dr. Gwatkin has certainly been closely associated with many of these new developments, and it comes as no surprise that he should have directed his energies to the production of a monograph. As is readily admitted in the preface, the b o o k derives from an earlier review on the subject of cell surface interactions in fertilisation. Accordingly, two of the questions that must be asked are to what extent this lengthier treatment maintains the excellent standard of the review, and whether the b o o k form is indeed justified by the inclusion of new and critically presented information. The title itself is somewhat misleading for, the erroneous distinction between man and mammals apart, few results are presented that relate purely to fertilisation in man. This is regrettable but stems, of course, from a lack of rigorous information. An overall impression of the 15 chapters is one of variable quality and length, and the sequence of presentation is not altogether logical. Chapters 1 and 13, dealing respectively with historical aspects of the subject and metabolic changes at fertilisation, do n o t exceed two and a half printed pages whilst Chapter 14, dealing with the fate of the millions of spermatozoa deposited in the female tract, amounts to no more than a single side. In Chapters 2 and 3, dealing with eggs and spermatozoa, the formation and maturation of the gametes is treated quite superficially whereas discussion of the nature of their membranes -- if not the individual organelles -- is crisp and authoritative. Chapter 4 surveys gamete transport in the female in three and a half sides plus two tables: several recent findings are highlighted, such as the critical rSle of cilia rather than musculature in promoting egg transport in the ampulla, b u t the fertilisable life of eggs presented in Table 1 is n o t a very meaningful figure without further explanation. Does this represent the potential to undergo sperm penetration and pronuclear formation, or does it refer to the lifespan during which penetration will subsequently give rise to a viable e m b r y o ? The principal site of insemination (i.e., semen deposition) listed in Table 2 needs to be corrected for the
252
pig and dog, in both of which species the bulk of the ejaculate enters the uterus, n o t the vagina. A valuable discussion of in vitro fertilisation is presented in Chapter 5, with useful details of a system for gametes of the golden hamster, but w h y should this appear before chapters dealing with sperm capacitation, the acrosome reaction, and the ensuing events of sperm attachment, penetration and fusion? In fairness to the author, perhaps because techniques of in vitro fertilisation have enabled processes such as capacitation and membrane vesiculation of spermatozoa to be analysed, b u t this is scarcely adequate justification for putting the cart before the horse. The precise character of sperm surface changes in the female tract is still to be resolved, but this reviewer does n o t like the notion that full capacitation occurs in the uterus of mammals. It seems more probable that the uterus and oviducts act synergistically to facilitate this change which, from the point of view of the e c o n o m y of acrosomal enzymes and sperm energy reserves, would more logically be completed in the vicinity of the eggs. Reasoning in the same vein, the acrosome reaction might best be stimulated by components emanating from or remaining in association with the zona pellucida. And, again in contrast to Gwatkin's viewpoint, recent studies suggest that much of the sperm hyaluronidase can be liberated before the acrosome reaction is conspicuous. Mechanisms for binding spermatozoa to the zona pellucida, and those underlying prevention or manipulation of polyspermy, represent active interests of Gwatkin's group, this being well conveyed in the detailed and enthusiastic flavour of these chapters. The final chapters dealing respectively with parthenogenesis and unanswered problems related to fertilisation are also timely, and the bibliography is comprehensive and an invaluable feature of the book. Criticisms of a general nature concern the quality of the photographs which would have been better printed on glossy paper, and the scant attention paid to p r o o f reading: many typographical errors remain, with one particular howler on p. 14 where the dry weight of a bull spermatozoon is presented as 16.5 × 1012g -- clearly n o t a haploid cell! Nevertheless, because the b o o k is well-written and concise, stimulating in terms of emphasizing current areas of gamete research in mammals, and none t o o expensive by modern standards, its publication is welcome and it surely deserves to join the shelves of research institutes and university departments. R.H.F. H U N T E R
(Edinburgh, Great Britain)
NEW TEXT ON UTERINE PHYSIOLOGY
Biology of the Uterus. 2nd Edition of Cellular Biology of the Uterus (ed. in 1967}. R.W. Wynn (Editor). Plenum Press, New York, N.Y., 1977, 748 pp., tables, figures, plates and references. "Biology of the Uterus", edited by R.W. Wynn in 1977, is a new version of "Cellular Biology of the Uterus" published ten years ago. According to