title: Vitreous and plasma changes of endothelin-1, adrenomedullin and vascular endothelium growth factor in patients with proliferative diabetic retinopathy.
abstract: To assess vitreous and plasma changes of vascular endothelial growth factor A (VEGF-A), adrenomedullin (ADM) and endothelin-1 (ET-1) in proliferative diabetic retinopathy (PDR).
  
  
  
  9 patients with PDR in type 2 diabetes (T2DM) and 11 age-matched non-diabetic patients were enrolled. The levels of VEGF-A, ADM and ET-1 were measured using an enzyme (ELISA) and a radioimmunoassay (RIA) both in vitreous and plasma samples.
  
  
  
  Vitreous ADM and VEGF-A levels were significantly higher in PDR patients (p=0.04 and p=0.02), whereas no differences were found in ET-1 levels (p=0.29). Plasma ADM levels were significantly higher in the PDR group (p<0.01), whereas no significant differences were found in the plasma ET-1 and VEGF-A levels (p=0.30 and p=0.37). The ADM vitreous/plasma ratio was significantly reduced in PDR group.
  
  
  
  The role of ET-1 in advanced PDR is still controversial; it has been supposed a role limited to induce hypoxic state and promote angiogenesis in the early phases. Once the neo-angiogenic process starts, other mediators are mainly involved as VEGF and ADM. Our findings suggest that ADM is an important marker of advanced PDR as well as VEGF. Conversely, ET-1 is not significantly involved in the advanced stage of PDR.
authors.affiliation: Department of Medical-Surgical Sciences and Biotechnologies, U.O.S. Ophthalmology, "Sapienza" University of Rome, Terracina, Italy. serena.fragiotta@uniroma1.it.
authors.forename: E M
authors.initials: EM
authors.lastname: Vingolo
authors.forename: S
authors.initials: S
authors.lastname: Fragiotta
authors.forename: M
authors.initials: M
authors.lastname: Mafrici
authors.forename: A
authors.initials: A
authors.lastname: Cutini
authors.forename: C
authors.initials: C
authors.lastname: Marinelli
authors.forename: A
authors.initials: A
authors.lastname: Concistrè
authors.forename: G
authors.initials: G
authors.lastname: Iannucci
authors.forename: L
authors.initials: L
authors.lastname: Petramala
authors.forename: C
authors.initials: C
authors.lastname: Letizia
mesh_terms: D053607:Adrenomedullin / Q000097:blood / Q000378:metabolism*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism; D003930:Diabetic Retinopathy / Q000378:metabolism*; D019332:Endothelin-1 / Q000097:blood / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D042461:Vascular Endothelial Growth Factor A / Q000097:blood / Q000378:metabolism*; D014822:Vitreous Body / Q000378:metabolism
chemical_list: D019332:Endothelin-1; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D053607:Adrenomedullin