PDE4 AND PDE5 REGULATE CYCLIC NUCLEOTIDES RELAXING EFFECTS ON HUMAN UMBILICAL ARTERIESPD.5Santos-Silva, A JÁlvarez, ECairrão, EVerde, IAuthor information1 Universidade da Beira Interior, Covilhã, Portugal, 2 Centro Hospitalar da Cova da Beira E.P.E, Covilhã, PortugalHypertension 48(4):p 770, October 2006.Copyright © 2006 American Heart Association, Inc.