The fate of the male germ cell : [proceedings of a Symposium on the Fate of the Male Germ Cell, held December 5-7, 1996, in Hamburg, Germany

THE FASCINATION The male germ cell is the only cell of the human organism that leaves the body when it has achieved its final, highly sophisticated structure and properties. The male germ cell is designed for one purpose only: to reach the female gametes and to fertilize them. The various stages in the development of the male germ cell are characterized by proliferative phases, by the recombination of the maternal and paternal chromosomes, and by the differentiation and development of a specialized transport vehicle, the spermato­ zoon. Furthermore, the establishment of a special pool of stem cells, the spermatogonia, guarantees the continuity of the sperm-generation process from puberty to old age. THE FATE OF THE MALE GERM CELL The destiny of any individual germ cell is determined by a program that we know only in fragments. On the one hand every human male is able to produce many billions of germ cells in his lifetime, yet the chance of any single sperm reaching and fertilizing the female germ cell is exceedingly rare. A fertility disturbance means that somewhere during the complicated playing out of the germ cell program mistakes are made, and the program fails. It is still a fact that more than 50% of men presenting with male factor infertility have to be diagnosed as idiopathic, largely because of our lack of knowledge and conse­ quent lack of appropriate diagnostic tools. Front Matter....Pages i-xv Human Reproduction....Pages 1-15 Human Y Chromosome Deletions in Yq11 and Male Fertility....Pages 17-30 Frequency of Y-Chromosome Microdeletions (Yq11.22–23) in Men with Reduced Sperm Quality Requesting Assisted Reproduction....Pages 31-35 Histone Gene Expression and Chromatin Structure during Spermatogenesis....Pages 37-48 Histone Gene Expression in the Human Testis....Pages 49-50 Endocrine Control of Germ Cell Proliferation in the Primate Testis....Pages 51-58 Quantification of Somatic and Spermatogenic Cell Proliferation in Testes of Ruminants....Pages 59-60 The Immortalized Mouse Germ Cell Lines GC-1spg and GC-2spd as a Model for Mitochondrial Differentiation during Meiosis....Pages 61-63 A Novel Endozepine-Like Peptide (ELP) is Exclusively Expressed in Male Germ Cells....Pages 65-66 Investigation on the Proliferation of Spermatogonia in Normal and Pathologic Human Seminiferous Epithelium....Pages 67-68 Rapid Method to Detect CIS-Cells....Pages 69-70 Testicular Tumor Cells Pass through the Epididymal Ducts....Pages 71-72 AgNOR in Human Leydig Cell Tumors....Pages 73-74 Endocrinological Disturbances in Germ Cell Tumour Patients....Pages 75-76 Reinvestigation of Patients After Primary Therapy of Testicular Tumor....Pages 77-78 Carcinoma- in - Situ in Testes with Germ Cell Tumour....Pages 79-80 Intratesticular Sperm Extraction....Pages 81-88 Molecular Pathophysiology of the Pituitary-Gonadal Axis....Pages 89-97 Fetal and Perinatal Influence of Xenoestrogens on Testis Gene Expression....Pages 99-110 Protease-Protease Inhibitor Interactions in Sertoli Cell-Germ Cell Crosstalk....Pages 111-123 New Aspects of Leydig Cell Function....Pages 125-138 Sertoli Cell-Specific Gene Expression in Conditionally Immortalized Cell Lines....Pages 139-142 Functional Markers for Fetal and Postnatal Differentiation of Rat Leydig Cells....Pages 143-144 Enzyme Histochemical Addition to Morphological Features of Leydig Cells in Senium....Pages 145-146 Differential Display PCR Cloning of W/W v -Mutant Testis Specific Genes....Pages 147-149 Immunoreactivity for Glial Cell Markers in the Human Testis....Pages 151-152 Insulin-Like Growth Factor-Binding Protein (IGFBP)-5 in Human Testicular Tubules....Pages 153-154 A Novel Role for Atrial Natriuretic Peptide (ANP) in Testis....Pages 155-156 Nerve Growth Factor (NGF) Receptors in Male Reproductive Organs....Pages 157-158 Delayed Onset of Spermatid Elongation on the Pubertal Golden Hamster Testis Depends on a Developmental Deficiency of Leydig Cell-11ß-HSD....Pages 159-160 Compartmentalization of the Intertubular Space in the Human Testis....Pages 161-162 Microcirculation and the Vascular Control of the Testis....Pages 163-180 Expression of VEGF and its Receptors and Capillary Density in Leydig Cell Tumors of the Human Testis....Pages 181-182 Angioarchitecture of the Human Spermatic Cord....Pages 183-184 Morphological and Functional Aspects of the Human Spermatic Cord Veins....Pages 185-186 Semen Analysis after Treatment of Varicocele by Antegrade Scrotal Sclerotherapy....Pages 187-188 VEGF Modulates the Capillaries of the Human Epididymis....Pages 189-190 Endothelin-1 and Its Receptors in the Human Epididymis....Pages 191-192 The Role of Apocrine Released Proteins in the Post-Testicular Regulation of Human Sperm Function....Pages 193-219 The Molecular Biology of the Sperm Surface....Pages 221-232 Purification and Structural Analysis of Sperm CD52, a GPI-Anchored Membrane Protein....Pages 233-234 Measurement of Calcium in Single Human Spermatozoa....Pages 235-237 Putative Role of a Serpin in Modulation of Acrosome Reaction....Pages 239-240 Immunoelectron Microscopic Studies on Outer Dense Fibres....Pages 241-242 The Use of Spin-Labelled Phospholipid Analogues to Characterize the Transverse Distribution of Phospholipides and the Activity of Phospholipase-A2 in the Cell Membrane of Bull Spermatozoa....Pages 243-244 Interactions between Leukocytes and the Male Reproductive System....Pages 245-252 Oxytocin and Male Reproductive Function....Pages 253-264 Sensory Innervation of the Human Penis....Pages 265-266 The Uterine Peristaltic Pump....Pages 267-277 Egg-Cumulus-Oviduct Interactions and Fertilization....Pages 279-289 The Cell Biology of Fertilization....Pages 291-299 The Role of Carbohydrates in Sperm-Egg Interaction....Pages 301-310 X-Ray Crystallographic Analysis of Boar PSP-I/PSP-II Complex....Pages 311-312 The Zona Pellucida “Receptors”....Pages 313-328 Back Matter....Pages 329-332 Papers from a December 1996 symposium present the latest research on fundamental aspects of sperm production and maturation and the destiny of spermatozoa within the female reproductive tract. Contains sections on genes, chromosomes, and fertility; germ cell differentiation and tumorigenesis; the role of testicular accessory cells; compartmentalization, vascularization, and angiogenesis; post- testicular sperm maturation; control of the male and female tracts; and gamete interaction and fertilization. Includes b&w photos. Most of the research originates in Germany, and is intended to encourage development of treatments for male infertility