The International Symposium on Prostaglandins and Related Compounds, first held in Vienna 1972, revisited the city after 24 years for the 10TH Symposium. For the many re searchers working in this multi-disciplinary field it was an opportunity to exchange their ex periences and share new data with colleagues from all around the world. This scientific exchange was largely encouraged by the unseasonably cold and rainy weather. For the first time, there was quite a large attendance from the former Communist countries. Eugene Garfield prepared a key note address delivered during the meeting (The Sci entist 1996, 12) reviewing the contribution of the Nobel Laureates U.S. von Euler, l.R. Vane, S.K. Bergstrom, and B.I. Samuelsson, discussing the relevance of the more than 40,000 pa pers in this area published since 1991. Overall, there is still a rapidly growing interest, and in particular a great variety of clinical applications of this family of compounds which were dis cussed in detail during the meeting. Beside the lectures there were 19 workshops covering nearly all the topics of key in terest. All the speakers were invited to prepare a manuscript which has resulted in the volume now in your hands. Special thanks to Dr. Patrick Wong and the new publisher of this series who helped to publish the proceedings in the usual quality and reasonable period of time. Looking forward to seeing all of you again in Florence in 1999, hopefully with much more sun."

The International Symposium on Prostaglandins and Related Compounds, first held in Vienna 1972, revisited the city after 24 years for the 10TH Symposium. For the many re searchers working in this multi-disciplinary field it was an opportunity to exchange their ex periences and share new data with colleagues from all around the world. This scientific exchange was largely encouraged by the unseasonably cold and rainy weather. For the first time, there was quite a large attendance from the former Communist countries. Eugene Garfield prepared a key note address delivered during the meeting (The Sci entist 1996, 12) reviewing the contribution of the Nobel Laureates U.S. von Euler, l.R. Vane, S.K. Bergstrom, and B.I. Samuelsson, discussing the relevance of the more than 40,000 pa pers in this area published since 1991. Overall, there is still a rapidly growing interest, and in particular a great variety of clinical applications of this family of compounds which were dis cussed in detail during the meeting. Beside the lectures there were 19 workshops covering nearly all the topics of key in terest. All the speakers were invited to prepare a manuscript which has resulted in the volume now in your hands. Special thanks to Dr. Patrick Wong and the new publisher of this series who helped to publish the proceedings in the usual quality and reasonable period of time. Looking forward to seeing all of you again in Florence in 1999, hopefully with much more sun."

Evidence accumulated over the past decade show that gonadal steroid hormones participate in an important way in the physiological and pa thophysiological regulation of the cardiovascular system. The hor monal profile appears to put males at a disadvantage biologically in terms of cardiovascular diseases. The incidence of hypertension is higher in men than in pre-monopausal women indicating an influence of gender on the hypertensive disease process. Males and females have equivalent cholesterol levels until puberty but males suffer an ex ponential increase in heart disease in their forties, while the female rise does not start until a decade later, after menopause. Animal and human studies provided ample evidence, that estrogens lower the levels of low density lipoproteins and keep high density lipoproteins elevated. These changes may be advantageous in the prevention of heart diesease. Co ronary artery atherosclerosis has been shown to be more pronounced in ovarectomized female monkeys as in intact females. Androgen, con versely, lowers the high density lipoproteins and elevates low density lipoproteins. Regarding blood pressure, it is well established that hypertension is more severe or develops more rapidly in male than fe male rats in several genetic forms of hypertension, and that gonadal steroid hormones are probably playing an important role in explaining this observation. Risk factors of human hypertension and coronary heart dies ease include menopause and ovarectomy."

This book represents the first of the ALZA CONFERENCE SERIES which will deal with a wide variety of topics of biomedical interest. These Conferences are planned to cover a range of subjects from the molecular level, such as drug receptor and drug membrane interactions, to the organ and organismal levels and the dynamics of drug therapy. This year's topic is "PROSTAGLANDINS." It is rapidly becoming clear that prosta glandins are of great interest and potential utility in therapeutics. An understanding of the role of prostaglandins in the regulation of cell processes should provide insight into the understanding of a variety of difficult and intransigent fields such as cancer, allergy, and transplant rejection. We hope that this Conference may focus attention on novel approaches to these areas. We wish to thank our distinguished Chairmen and guests for their attendance. The papers and dis cussions were prepared by Yvonne Hendrickson, using an ATS/360 Text-Editing System; we acknowledge with gratitude her skill, patience, and hard work. P.W.R. B.B.P.

There is much evidence to suggest that prostaglandins may have a physiological role to play in the control of thyroid gland metabolism, although the precise nature of this role remains to be defined. Prostaglandins have been found in normal thyroid tissue, and there is evidence of increased levels in some, but not all, cases of medullary carcinoma of the thyroid. which may account for the associated diarrhea. Exogenous prostaglandins, like TSH, bind to thyroid plasma mem branes, stimulate the adenylate cyclase-cyclic AMP system, thyroid hormone secretion, iodide organification, colloid droplet formation, glucose oxidation, and 32p incorporation into phospholipids. Prosta glandins of the E series are the most potent, although their maximal effects are generally less than the maximal effects of TSH. The interrelationships existing between TSH and prostaglandins have been the subject of intensive investigation, but as yet no one uni fying concept has emerged. TSH and prostaglandins have been shown to occupy different receptors on the thyroid plasma membrane. Al though TSH can increase intracellular prostaglandin levels, probably as a result of increased synthesis, prostaglandins do not appear to be essential intermediates in TSH action on adenylate cyclase. The pos sibility that prostaglandins are part of a negative feedback system con trolling TSH action is, as yet, a tentative hypothesis, and further work will be required to unravel the interrelationships between these sub stances that now appear to be far more complex than has been envisaged thus far."