Bulletin Spring‧Summer 1995

Front ( f r omr i g h t ) : P r o f . JonesandD r. Wise Back( f r omr i g h t ) : D r. Wongandtwograduate assistants activate the receptor system on its own, but can, to some extent, inhibit the action of the natural agonist. It hence represents an important clue to the structure of a pure antagonist. In Search of an Antagonist for Prostacyclin Receptors The natural agonist 'prostacyclin' is best known for its ability to prevent the clumping of blood platelets and to increase blood flow through tissues. However, it is also a powerful stimulant of sensory nerve endings. Released with prostaglandin E2at the site of inflammation, it can cause redness, heat, swelling and pain. CUHK researchers are now trying to develop antagonists for the prostaglandin receptors in the body. In the case of the prostacyclin receptor, apartial agonist which is structurally distinct from the native prostacyclin molecule has been identified. Synthetic pathways to relatives of this structure have been devised and are under investigation. Unequivocal structural identification of each final compound relies heavily upon sophisticated chemical analysis such as nuclear magnetic resonance spectometry and mass spectometry. Biological Testing Any potential prostacyclin receptor antagonist then undergoes careful biological testing, which involves the use of isolated tissue preparations (like asegment of intestine) obtained from men and animals. Experience has proved that it is possible to keep these preparations 'alive' by immersing them in awarmed salt solution, which is a source of oxygen and nutrients. The preparation responds to the prostacyclin agonist as it would in the body, and thus Prof . RobertL Jones received hisundergraduate r a i n i n g at theSchool ofPharmacy,U n i v e r s i t yof London,and then completed hisdoctoralthesis at the U n i v e r s i t y of Edinburghin 1970.Heremained in E d i n b u r g h ,f i r st as lecturer andthenasreaderin pharmacology, before coming to C U H K . P r o f . Jones'research interestsare m a i n l y concerned w i t h the p h a r m a c o l o g i c a l investigationof noveleicosanoid (20-carbon f a t t y acid) products.Hehas just been awardedaD.Sc.degree by theUniversityof London f or hisworkon prostaglandin receptors. Dr. HelenWisegraduatedin pharmacology f r om the University of Bristol andobtainedherdoctorate f r om the U n i v e r s i t y of Bath i n 1979. She joined thi s university in1991afterspending 12 yearsin i n d u s t r i a l pharmacologyw i t h GlaxoResearch and Development ( U K ) . D r. Wise's interests p r i n c i p a l l yconcern receptor- effectormechanisms, and hercurrentresearch is focussed upon thecharacterizationof prostaglandin receptors involved in inflammation. D r. Henry N. C. Wonggraduated f r om The Chinese U n i v e r s i t y of Hong Kongin 1973and obtained his doctorate f r om University College Londonin 1976.He returnedto thisuniversityin 1983andisnowa reader in theDepartmentofChemistry.D r . Wong's research interests includethe synthesis of non-natural and natural moleculesw i t h theoretical and p r a c t i c a l i mp l i c a t i o n s , a well astheuseof organosilicon and organotincompounds inorganicsynthesis. In 1994,D r. Wongwasawarded aD.Sc.degree bytheU n i v e r s i t y of London f or hisworkonsyntheticorganic chemistry. permits the activity of the potential antagonist to be tested. Useful Results Anticipated The programme of synthesis is being continually modified in the light of the results of the biological testing. It is hoped that any potential receptor antagonists developed in this project will have distinct advantages over the currently available aspirin-like drugs. These widely used agents exert their anti-inflammatory and analgesic effects by blocking the biosynthesis of prostaglandins in the affected tissue, for example the knee joint. However they also block prostaglandin biosynthesis throughout the body, and this may not be beneficial, The greater selectivity of the receptor antagonist may be a distinct advantage. Research 20