Prostanoid receptors: ontogeny and implications in vascular physiology

Prostanoids exert significant effects on circulatory beds. They play a role in the response of the vasculature to adjustments in perfusion pressure an d oxygen and carbon dioxide tension, and they mediate the actions of numero us factors. The role of prostanoids in governing circulation of the perinat e is suggested to surpass that in the adult. Prostanoids are abundantly gen erated in the perinate. They have been implicated in autoregulation of bloo d flow as studied in brain and eyes. Prostaglandins are also dominant regul ators of ductus arteriosus tone. The effects of these autacoids are mediate d through specific G protein-coupled receptors. In addition to the pharmaco logical characterization of the prostanoid receptors, important advances in understanding the biology of these receptors have been made in the last de cade. Their cloning and the development of animals with disrupted genes of these receptors have been very informative. The involvement of prostanoid r eceptors in the developing subject, especially on brain and ocular vasculat ure and on ductus arteriosus, has also begun to be investigated; the expres sion of these receptors changes with development. Some but not all of the o ntogenic changes in these receptors are attributed to homologous regulation . Interestingly, in the process of elucidating their effects, functional pe rinuclear prostaglandin E-2 receptors have been uncovered. This article rev iews prostanoid receptors and addresses implications on the developing subj ect with attention to vascular physiology.