title: Pupillocynetic activity of substance P in systemic sclerosis.
abstract: OBJECTIVE
  In systemic sclerosis (SSc), dysfunctions of peripheral nervous system (PNS) have been observed. Substance P (SP) instillation in human eye induces a cholinergic-independent pupil myosis. Pupil basal diameters (PBD) and pupil responsiveness to SP, expressed as area under the curve (AUC), were studied by pupillometry to assess SP-ergic fiber state and function in SSc.
  
  
  METHODS
  Forty SSc patients [24 with limited (lSSc), 16 with diffuse (dSSc) disease] and 40 controls underwent pupillometric evaluation. After evaluation of PBD, SP 10-3 M was instilled in one eye and placebo in the contralateral eye. Antinuclear (ANA), anticentromere (ACA), and anti-Scl-70 autoantibodies were correlated with PBD and AUC.
  
  
  RESULTS
  PBD was significantly lower in SSc patients versus controls (p < 0.001). PBD was minor in lSSc versus both dSSc and controls (p < 0.05), but no difference was found between dSSc and controls. In SSc, SP 10-3 M induced greater myosis compared to controls (p < 0.001). SP 10-3 M-induced myosis was higher in lSSc versus both dSSc and controls (p < 0.05). ACA significantly correlated with decreased values of PBD and AUC (p < 0.001).
  
  
  CONCLUSIONS
  Our results show that PBD is reduced in patients with SSc and that SP induces a more intense myosis in SSc than controls. Moreover, in lSSc PBD is lower and SP increases the myosis in lSSc compared to dSSc and controls. This suggests a peculiar dysfunction of PNS in patients with the limited subset of SSc.
authors.affiliation: Department of Medicine, Section of Rheumatology, Headache, and Nephrology, University of Florence, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Del Rosso
authors.forename: Luca
authors.initials: L
authors.lastname: Bertinotti
authors.forename: Umberto
authors.initials: U
authors.lastname: Pietrini
authors.forename: Andrea
authors.initials: A
authors.lastname: Messori
authors.forename: Marcello
authors.initials: M
authors.lastname: Fanciullacci
authors.forename: Roberto
authors.initials: R
authors.lastname: Casale
authors.forename: Roberto
authors.initials: R
authors.lastname: Giacomelli
authors.forename: Sergio
authors.initials: S
authors.lastname: Generini
authors.forename: Riccardo
authors.initials: R
authors.lastname: Sicuteri
authors.forename: Alberto
authors.initials: A
authors.lastname: Pignone
authors.forename: Franco
authors.initials: F
authors.lastname: Cozzi
authors.forename: Marco
authors.initials: M
authors.lastname: Matucci-Cerinic
mesh_terms: D000368:Aged; D001323:Autoantibodies / Q000032:analysis; D005260:Female; D006801:Humans; D007498:Iris / Q000294:innervation; D008297:Male; D008875:Middle Aged; D009475:Neurons, Afferent / Q000187:drug effects / Q000502:physiology; D011680:Pupil; D012025:Reflex, Pupillary / Q000187:drug effects*; D012595:Scleroderma, Systemic / Q000175:diagnosis* / Q000276:immunology / Q000503:physiopathology*; D013373:Substance P
chemical_list: D001323:Autoantibodies; D013373:Substance P