Male Reproductive Function and Semen

I Male Reproductive Function and the Composition of Semen: General Considerations.- 1. Functional Dualism of the Testis.- The beginnings: conceptual formulation of testicular function.- Exocrine and endocrine activity.- 2. Male Reproductive Tract: Main Characteristics.- Representative accessory organs in mammals.- Prostate gland.- Seminal vesicle.- Bulbo-urethral (Cowper's) gland.- Preputial and urethral (Littre's) glands.- Accessory organs in marsupials.- Accessory organs in birds, frogs, reptiles, fishes and invertebrate animals.- 3. Coordination of Male Reproductive Function by Extragonadal Hormones and Environmental Factors.- Control of male reproductive function by gonadotrophins (FSH and LH) and the hypothalamic gonadotrophin-releasing hormone (GnRH).- Sexual dimorphism of the hypothalamus and other parts of the brain.- Prolactin and the pineal antigonadotrophic factor.- Regulatory hormonal mechanisms in invertebrate animals.- Influence of nutrition on male fertility.- 4. Cardinal Properties of Spermatozoa.- Exploratory observations on sperm structure, physiology and chemistry.- Sperm passage in the male and female genital tracts.- Correlations between motility and fertilizing ability.- 5. General Features of the Seminal Plasma.- Species differences.- Peculiarities of chemical composition.- Role in male reproductive performance.- Pheromonal properties.- Effects on spermatozoa.- 6. Spermatophores and Spermatophoric Reaction.- Delivery of semen by spermatophores.- Spermatophore of the Giant North-Pacific Octopus.- Spermatophoric reaction.- II Methodological Guidelines in the Study of Male Reproductive Organs.- 1. Andrological Examination of the Testis and Androgen Assays.- Gross inspection of the male gonad.- Testicular biopsy.- Quantifiable techniques for the analysis of biopsy specimens.- Evaluation of testicular function by hormone assays.- Evaluation of the potency of androgens.- 2. Cannulation, Micropuncture, Perfusion and Transplantation Techniques.- Sampling of testicular lymph.- Withdrawal of testicular and epididymal semen.- Perfusion of the testis and epididymis.- Perfusion of the prostate and superfusion of prostatic tissue slices.- Transplantation of testicular and accessory gland tissues.- 3. Isolation of Seminiferous Tubules and Disaggregation of Germinal Cells and Sertoli Cells.- Separation of seminiferous tubules from testicular interstitium.- Functional characteristics of isolated seminiferous tubules.- Disaggregation of different types of germinal cells.- Sertoli-cellenriched preparations.- 4. Cell and Organ Cultures.- Androgen secretion in fetal testis culture.- Culture techniques in the study of spermatogenesis.- Biochemical events in Sertoli cell cultures.- Maturation of spermatozoa in cultured epididymal tubules.- Prostate explants.- III Collection, Examination, Quality Rating and Storage of Ejaculated Semen.- 1. Collection of Whole and Split Ejaculates, and Separation of Spermatozoa from Seminal Plasma.- Methods for collecting whole and split ejaculates.- Separation of spermatozoa from seminal plasma in ejaculated semen.- Removal of seminal debris and seminal gel.- 2. Separation of Motile from Immotile, and Male-determining from Female-determining Spermatozoa.- Methods for separating motile from immotile spermatozoa.- Separation of male- and female-determining spermatozoa and manipulation of sex ratio.- The fluorochrome test in human chromosomal aberrations.- 3. Examination of Spermatozoa and Isolated Structural Components.- Dissection of spermatozoa.- Spatial relationships between sperm head, cytoplasmic droplet, axial filament complex, mitochondrial sheath, dense fibres and fibrous sheath.- Mechanical and chemical separation of sperm structure components.- 4. Quality Rating of Semen in Andrological Practice.- Criteria used in semen evaluation.- Devices for the appraisal of sperm density and motility, and differentiation between live and dead spermatozoa.- Sperm abnormalities and polymorphism.- Microbiological inspection of semen.- The cervical mucus penetration and postcoital tests.- Other methods for quality rating of semen.- 5. Storage of Semen for Artificial Insemination.- Prolongation of sperm viability by storage of semen.- Storage techniques.- Species-linked and individual differences in the keeping quality of semen.- Assessment of damage in stored spermatozoa.- IV Testis and Testicular Semen.- 1. Spermatogenesis.- General characteristics of seminiferous tubules.- Normal and abnormal spermatogenesis.- Sertoli cells and the hormonal control of spermatogenesis.- Inhibin.- Biosynthesis of nucleic acids and proteins in the germinal epithelium.- Enzymes as biochemical markers of differentiating germ cells.- 2. Steroidogenesis.- Leydig cells as providers of testicular androgen.- Biosynthesis of testosterone in the testis.- Pattern of testosterone release; episodic, circadian and seasonal fluctuations; effect of sexual arousal.- Testosterone binding to target cells and reduction to dihydrotestosterone.- Male gonad, skin and brain as androgen-sensitive organs.- Male oestrogens.- 16-Androstenes as olfactory sex stimulants.- 3. Testicular Semen.- General characteristics of testicular semen.- Production of spermatozoa by the testes in relation to the sperm output in ejaculated semen.- Testicular plasma as a secretory product of the testis.- Entry of substances into testicular semen.- Metabolic properties of testicular spermatozoa.- Pathological accumulation of fluid in the testis; spermatocele and hydrocele.- V Epididymis and Epididymal Semen.- 1. Functional Characteristics of the Epididymis.- Epididymal duct as conduit for spermatozoa.- Resorptive properties of the epididymal epithelium.- Role of the epididymis in relation to spermatozoa.- Effect of androgen withdrawal on epididymal function.- Androgen transport in the epididymis.- 2. Epididymal Spermatozoa.- Functional and structural changes in spermatozoa undergoing epididymal maturation.- Physicochemical and biochemical events associated with the passage of spermatozoa in the epididymis.- Other aspects of sperm maturation.- 3. Epididymal Plasma.- Main biochemical features of the epididymal plasma.- Characteristic constituents of the epididymal plasma: glycerylphosphorylcholine,carnitine, certain mucoproteins and enzymes.- 4. Metabolism of the Epididymis and Epididymal Semen.- Oxidative metabolism of lipids.- Glycolysis.- Role of nucleotide coenzymes.- VI Vas Deferens and Vasectomy.- 1. Structural and Functional Features of the Deferent Duct.- The human vas.- Varicocele and spermatocele.- The vas in animals.- The vas as a conduit for spermatozoa.- Response to noradrenaline and enkephalin.- Secretory and absorptive function.- Aplasia attributable to agenesis and cystic fibrosis.- 2. Vasectomy and Vasoligation.- Andrological hazards and consequences of vasectomy, vasoligation and vasocclusion.- Sperm granuloma and the appearance of spermagglutinating and -immobilizing antibodies.- Postvasectomy reconstruction of the deferent duct.- VII Secretory Function of the Prostate, Seminal Vesicle, Cowper's Gland and Other Accessory Organs of Reproduction.- 1. Secretory Mechanisms.- 2. Androgen-dependent Maintenance of Growth, Metabolism and Secretory Activity in Male Accessory Organs.- Androgen indicator tests.- Accessory organs as targets for longlasting testosterone action.- Relationship between androgen levels and the functional state of the normal, hypertrophied and cancerous prostate in man.- 3. Overall Pattern and Mechanism of Hormonal Regulation.- Activation of target cells by testosterone and formation of the dihydrotestosterone-receptor complex.- Interaction of the androgenreceptor complex with chromatin and the ensuing synthesis of RNA, protein and enzymes.- Metabolic events triggered by androgen-evoked enzymatic activity.- Relative efficiency of androgenic steroids.- Effects of hormones other than testicular androgens on accessory organs.- 4. Comparative Andrological Aspects.- Man.- Bull.- Ram and billygoat.- Boar.- Stallion and jackass.- Dog and cat.- Laboratory animals.- Wildlife.- VIII Biochemistry of Spermatozoa: Chemical and Functional Correlations in Ejaculated Semen, Andrological Aspect.- 1. Chemical and Metabolic Characteristics of Ejaculated Spermatozoa; Comparative Viewpoint.- Fructolysis and respiration.- Pyruvate dismutation and carbon dioxide fixation.- Sperm lipid chemistry and metabolism.- Lipid peroxidation.- 2. Sperm Plasma Membrane; Permeability and Binding Properties.- Role of sulphydryl groups.- Regional differentiation of plasmalemma.- Ionic gradients and electric charge.- Membrane-bound enzymes and substance-specific binding sites.- Carboglutelin.- 3. Acrosome and Lysosomal Enzymes.- Constituent structures of the acrosome.- Acrosome reaction.- Acrosome as a specialized lysosome.- Acrosin and its proteolytic activity.- Acrosin inhibitors in seminal plasma.- The kinin-kallikrein system.- Glycosidases, hyaluronidase, neuraminidase, arylsulphatase, phosphatases and other acrosomal enzymes.- Bindin.- Lysosomal features of the cytoplasmic droplet.- 4. Sperm Nucleus: Nucleic Acid and Nuclear Proteins.- Haploid nucleus.- Deoxyribonucleic acid, protamines and histones in normal and defective spermatozoa.- Structure of mammalian sperm chromatin.- The question of DNA-polymerizing activity in the sperm nucleus.- Nucleoproteins of non-mammalian spermatozoa.- Questionable occurrence of ribonucleic acid in the nuclei of mature spermatozoa.- 5. Mitochondria and their Role in Sperm Metabolism and Energetics.- Mitochondrial sheath of the middle piece.- Sperm-specific lactate dehydrogenase.- Other mitochondrial enzymes and the cytochromecytochrome oxidase system.- Use of isolated sperm mitochondria in metabolic studies.- Energy-rich phosphorus compounds and the adenylate energy charge.- Link-up between the redox state of NAD and energy-yielding dehydrogenase-dependent oxidoreductions.- Energy derived from fructolysis.- Superiority of respiration and oxidative phosphorylation over glycolysis as a potential source of energy to spermatozoa.- 6. Flagellum and the Mechanochemical Basis of Motility.- Motility as the major energy-requiring process in spermatozoa.- The ATP-controlled movement-generating mechanism of the flagellum.- Tubulin, dynein and other axonemal proteins.- Deficiency of dynein and protein carboxyl-methylase in immotile spermatozoa.- 7. Cyclic Nucleotides and Other Promoters of Sperm Activity.- Cyclic AMP and cyclic GMP.- Adenylate cyclase and guanylate cyclase.- Protein kinase and phosphodiesterase.- Cyclic AMP, caffeine and theophylline as promoters of sperm motility and metabolism.- Other sperm activity enhancing agents.- IX Biochemistry of Seminal Plasma and Male Accessory Fluids; Application to Andrological Problems.- 1. Chemical Analysis of Seminal Plasma and Interpretation of Results.- General observations on analytical methods.- Post-ejaculatory changes in the seminal plasma in vitro.- Other factors influencing the composition of seminal plasma.- The importance of genotype.- 2. Ions, Free and Bound.- Electrolytes in seminal plasma.- Electrolytes in spermatophoric plasma.- 3. Proteins and Enzymes.- Electrophoretic pattern of proteins in seminal plasma and accessory fluids.- Calcium-binding proteins.- Zinc-binding proteins.- Lactoferrin and transferrin.- Protein hormones.- Proteolytic and lipolytic enzymes.- Nucleases, nucleotidases and other nucleolytic enzymes.- Seminal phosphatases.- Glycosidases and glycoprotein-glycosyltransferases.- Sulphydryl oxidase.- 4. Peptides, Amino Acids and Nitrogenous Bases.- Peptides.- Free amino acids.- Preponderance of glutamic acid.- Hypotaurine.- Spermine, spermidine and putrescine.- Choline, phosphorylcholine and glycerylphosphorylcholine.- Carnitine and acetylcarnitine.- Ergothioneine, 5-hydroxytryptamine, adrenaline and other nitrogenous bases.- 5. Fructose, Other Sugars, Polyols and Bound Carbohydrate.- Fructose as the principal sugar of seminal plasma.- Glucose, other saccharides and free acetylaminosugars.- Sorbitol, inositol and other polyols.- Glycerylphosphorylinositol.- Bound sugar, amino sugar and sialic acid.- 6. Lipids, Cholesterol and Steroid Hormones.- Comparison of the lipid composition and distribution in the seminal plasma and spermatozoa.- Cholesterol.- Patterns of steroid hormones in the seminal plasma.- Metabolic conversions and effects of seminal steroids.- 7. Prostaglandins and Other Organic acids.- Biosynthesis of prostaglandins in the seminal vesicle.- Prostaglandins in the seminal plasma and their relation to male fertility.- Citric acid.- Ascorbic acid.- Uric acid.- Lactic acid and pyruvic acid.- 8. Biochemical Basis of Interactions between the Male Accessory Secretions, and between the Seminal Plasma and Spermatozoa.- Coagulation and liquefaction of human semen.- Copulatory plug formation in rodents.- Gelation of boar semen.- Coating and decoating of spermatozoa by seminal plasma constituents.- Spermcoating antigens and sperm-inactivating antibodies in seminal plasma.- Ionic and metabolic exchange reactions between seminal plasma and spermatozoa.- 9. Examination of Whole Seminal Plasma and Split Ejaculatory Fractions as a Diagnostic Aid in Reproductive Disorders.- Anatomical defects in the male reproductive tract.- Inflammatory conditions.- Appraisal of the male's androgenic state, and hormonal effects.- Diabetes.- Nutritionally conditioned changes in the composition of seminal plasma.- Disturbances in the ejaculatory process.- Absorption of seminal constituents from the female reproductive tract.- Release of enzymes by damaged spermatozoa; correlations between quality of semen and the activity of transaminases and certain other enzymes in the seminal plasma.- X Effects of Pharmacological Agents: Andrological Aspects. Drug Abuse, Therapeutic Agents, Male Contraceptives, Occupational Hazards.- 1. Psycbomimetic and Psycbotberapeutic Drugs.- Narcotics and hallucinogens.- Antipsychotic, antianxiety and antidepressant drugs.- 2. Ampbetamines, Cocaine and Alcobol.- 3. Passage of Drugs and Otber Substances into Semen.- 4. Control of tbe Ejaculatory Process by Sympatbomimetic, Parasympatbomimetic and Autonomic-blocking Agents.- Contractile responses of the male reproductive tract during ejaculation.- Use of accessory organs for monitoring pharmacological effects in vitro.- 5. Chemosterilants as Potential Male Contraceptives.- 6. Dietary Factors, Food Additives and Antimetabolites.- Detrimental effects of certain dietary factors and food additives.- Metabolic analogues as potential antifertility agents.- 7. Cadmium-induced Damage in tbe Testis and Countereffect of Zinc and Selenium.- 8. Steroids and Otber Suppressors of Spermatogenesis Acting via tbe Pituitary Gland.- Rebound phenomenon.- Testosterone enanthate and danazol.- Other steroidal and nonsteroidal suppressors of gonadotrophic activity.- 9. Antiandrogens.- Cyproterone acetate, methylnortestosterone and flutamide.- Spironolactone.- 10. Antimitotic and Antimeiotic Cbemicals; Colcbicine, Alkylating Agents, Heterocyclic Compounds.- Colchicine.- Nitrogen mustards (haloalkylamines), ethyleneimines and sulphonoxyalkanes.- Nitrofuranes, nitropyrroles, nitroimidazoles and indazole derivatives.- 11. Chemotherapeutic Drugs, Industrial Chemicals and Pesticides.- Win.- 13,099.- Niridazole.- Cyclophosphamide and other cystostatic drugs.- Cimetidine.- Organochlorine compounds.- Dibromochloropropane.- Dibromopropanol, Tris-BP and dibromoethane.- Ethylene oxide cyclic tetramer.- Organophosphates.- Carbamates.- Paraquat.- 12. ?-Chlorohydrin.- 13. Biochemical Basis of Spermiostatic and Spermicidal Activity.- Enzyme inhibitors.- Sulphydryl-binding substances.- Surface-acting agents.- References.