1. Receptor Serine Kinases and Signaling by Activins and Inhibins.- 2. The Gene Expression of Activin Receptors in Rat Pituitary.- 3. Follistatin Physiology and Potential Mechanisms of Action in the Human.- 4. Inhibins, Activins, Follistatin, and GnRH: Regulators of Gonadotropin Subunit Gene Expression.- 5. Inhibin and Activin as Paracrine Regulators of Gonadal Function: In Vitro Model Systems.- 6. Production and Actions of Inhibin, Activin, and Follistatin in the Pituitary and Ovary.- 7. Expression of Inhibin Subunits, Follistatin, and Activin Receptors in Normal Testicular Cells and Testicular Tumors.- 8. Inhibin, Activin, and Follistatin: Observations on Their Role in the Physiology of Pregnancy.- 9. Changes of Activin A Secretion in Gestational Diseases.- 10. Two-Site Immunoassay for Native Inhibin A.- 11. Ultrasensitive Enzyme Immunoassays for Inhibins and Activins.- 12. Immunoassays for Activin and Follistatin: Results in Normal and Diseased Subjects.- 13. Circulating Inhibin.- 14. Evaluation of Matemal Serum Inhibin as a Marker for Complicated Pregnancy.- 15. Production of Inhibin-Related Peptides by Ovarian Tumors.- 16. Plasma Inhibin and Activin in Disease.- 17. Activin A: A Commitment Factor in Erythroid Differentiation.- 18. Effect of Activin A on the Formation of Pancreatic Endocrine Cells.- 19. The Role of Activin in Spermatogenesis in Fish.- 20. Control of Cell Differentiation and Morphogenesis by Activins During Early Amphibian Development.- 21. Neural Induction in the Frog Xenopus laevis.- 22. Transgenic Approaches to Study the Functions of the Transforming Growth Factor-? Superfamily Members.- 23. Activin Signaling Pathways and Their Role in Xenopus Mesoderm Formation.- 24. Activin Signal Transduction and the Role of TGF-? Superfamily in Cell Differentiation.- 25. The Role of Follistatin in Activin Signal Transduction.- 26. Transforming Growth Factor-? Receptors and Signal Transduction.- Short Communications from the Poster Session.- 27. Cytokine Inhibits Inhibin A Secretion in Cultured Rat Granulosa Cells.- 28. Mitosis and Inhibin Production in Ovarian Follicular Granulosa Cells During the Estrous Cycle of Rats.- 29. Induction of G1 Arrest by Activin A via Cooperative Modulation of Cyclin D2 and p21CIP1/WAF1 in Hybridoma Cells.- 30. Pharmacological Analysis of the Neurotrophic Effect of Activin.- 31. A Follistatin-Like Gene, mac25, as a Tumor Suppressor.- 32. Expresssion of Activin ?-Subunit and Type II Receptor Genes During Newt Spermatogenesis.- 33. Analysis of the Response of Human Embryonal Carcinoma Cells to Aetivin A.- 34. Regulation of Angiogenesis by TGF-? Superfamily.- Author Index.