title: Treatment of psoriasis with topical NG-monomethyl-L-arginine, an inhibitor of nitric oxide synthesis.
abstract: A double blind left, right comparative study was carried out in 17 psoriatic subjects to examine the influence of a topically applied inhibitor of nitric oxide (NO) synthesis on the pathogenic events of psoriasis. The inhibitor NG-monomethyl-L-arginine (L-NMMA) in aqueous cream BP was applied to one plaque while aqueous cream BP alone served as control. Compared with the control, the L-NMMA-treated side showed significant (77%) inhibition of NO production and a reduction in blood flow, confirming its bioavailability. L-NMMA significantly reduced staining for endothelial cells and intercellular adhesion molecule 1, while CD1a-positive Langerhans cells and CD8-positive suppressor cytotoxic T cells increased. CD4-positive lymphocytes and epidermal proliferation, as indicated by Ki-67 staining, were unaffected by this degree of inhibition of NO synthesis, and correspondingly significant clinical improvement was not found.
authors.affiliation: Department of Dermatology, Aberdeen Royal Infirmary, Foresterhill, Aberdeen, AB25 2ZN, U.K. a.d.ormerod@abdn.ac.uk
authors.forename: A D
authors.initials: AD
authors.lastname: Ormerod
authors.forename: P
authors.initials: P
authors.lastname: Copeland
authors.forename: S A
authors.initials: SA
authors.lastname: Shah
mesh_terms: D000328:Adult; D000368:Aged; D001682:Biological Availability; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D004311:Double-Blind Method; D004727:Endothelium / Q000166:cytology; D004791:Enzyme Inhibitors / Q000493:pharmacokinetics / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors* / Q000627:therapeutic use; D011565:Psoriasis / Q000188:drug therapy* / Q000201:enzymology / Q000503:physiopathology; D012039:Regional Blood Flow / Q000187:drug effects; D016896:Treatment Outcome; D019323:omega-N-Methylarginine / Q000493:pharmacokinetics / Q000627:therapeutic use*
chemical_list: D004791:Enzyme Inhibitors; D019323:omega-N-Methylarginine; D019001:Nitric Oxide Synthase