University of Vermont

About: University of Vermont is a education organization based out in Burlington, Vermont, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 17592 authors who have published 38251 publications receiving 1609874 citations. The organization is also known as: UVM & University of Vermont and State Agricultural College.

Cytokines of the Lung

Abstract: Communication between cells determines the steady-state composition of the lung in health and becomes a critical determinant of outcome in pathologic processes resulting in anatomic remodeling. This review presents the evolving concepts of the biology of cytokines (also known as peptide growth factors or biological response modifiers) in maintaining normal tissue growth and homeostasis. How these extracellular signaling proteins are involved in such pathologic disorders as spontaneous pulmonary fibrosis, sarcoidosis, pneumoconiosis, and the evolution and recovery from acute lung injury is also discussed. During the past decade the cytokines have come to the fore as important multifunctional mediators of cell behavior and cell-cell communication. A wide range of cellular responses are influenced or triggered when cytokines interact with cells. These include mitosis, chemotaxis, angiogenesis, cytoskeleton arrangement, immunomodulation, and extracellular matrix production. Cytokines influence cell behavior by binding to specific high affinity surface receptors on target cells. These receptors are linked in turn at the cell membrane to a complex array of intracellular signaling pathways. Individual cytokines may inhibit as well as promote cellular functions such as mitosis and thereby play a critical role in homeostasis of normal tissue elements. Hence, cytokines are intimately involved in normal tissue homeostasis as well as in processes eventuating in growth and remodeling. All cells produce and secrete cytokines at some time during their life. Each cytokine is capable of modulating more than one cellular function. Although produced by a variety of cell types, the triggers that induce a specific cytokine to be produced differ between cells. Many of the cytokines share regions of homologous nucleic acid sequences, suggesting that they are members of larger gene families. Given that tissues and cells are exposed to complex cytokine mixtures rather than to individual cytokines, recent attention has turned to understanding how cytokines interact. The combined effects of cytokine mixtures have proved to be both complex and unpredictable based on knowledge of the separate actions of the individual cytokines involved. In studies of the role of cytokines in lung disease, early research attention has focused on those cytokines released by alveolar macrophages (the so-called macrophage-derived growth factors). However, structural cells as well as immune effector cells of the lung are capable of cytokine production and release. The cytokines receiving the most attention to date in relation to pulmonary diseases include platelet-derived growth factor (PDGF), interleukin-1 (IL-1), transforming growth factor-beta (TGF-beta), tumor necrosis factor-alpha (TNF-alpha), insulinlike growth factor I (IGF-I), and, most recently, interleukin-6 (IL-6).(ABSTRACT TRUNCATED AT 400 WORDS)

Localization of D1 and D2 dopamine receptors in brain with subtype-specific antibodies.

Abstract: Five or more dopamine receptor genes are expressed in brain However, the pharmacological similarities of the encoded D1-D5 receptors have hindered studies of the localization and functions of the subtypes To better understand the roles of the individual receptors, antibodies were raised against recombinant D1 and D2 proteins and were shown to bind to the receptor subtypes specifically in Western blot and immunoprecipitation studies Each antibody reacted selectively with the respective receptor protein expressed both in cells transfected with the cDNAs and in brain By immunocytochemistry, D1 and D2 had similar regional distributions in rat, monkey, and human brain, with the most intense staining in striatum, olfactory bulb, and substantia nigra Within each region, however, the precise distributions of each subtype were distinct and often complementary D1 and D2 were differentially enriched in striatal patch and matrix compartments, in selective layers of the olfactory bulb, and in either substantia nigra pars compacta or reticulata Electron microscopy demonstrated that D1 and D2 also had highly selective subcellular distributions In the rat neostriatum, the majority of D1 and D2 immunoreactivity was localized in postsynaptic sites in subsets of spiny dendrites and spine heads in rat neostriatum Presynaptic D1 and D2 receptors were also observed, indicating both subtypes may regulate neurotransmitter release D1 was also present in axon terminals in the substantia nigra These results provide a morphological substrate for understanding the pre- and postsynaptic functions of the genetically defined D1 and D2 receptors in discrete neuronal circuits in mammalian brain