title: Gastric emptying effect by 4-aminopyridine in patients with chronic spinal cord injury.
abstract: BACKGROUND
  4-Aminopyridine (4-AP) given to patients with chronic spinal cord injury (SCI) has shown beneficial effects in some somatic and autonomic functions, although patients often develop dyspeptic symptoms. 4-AP is a potassium-channel blocker capable of altering gastro-pyloric functions as demonstrated experimentally. Our objective was to examine the influence of 4-AP treatment on gastric emptying in patients with chronic SCI.
  
  
  METHODS
  Gastric emptying was measured by the acetaminophen absorption test in 18 patients (9 with cervical and 9 with thoracic injury), and 9 healthy volunteers. Patients received increasing oral doses, 5 mg day(-1) of oral 4-AP (5-30 mg day(-1)), for 12 weeks. Patients were studied before and at the end of the last week of 4-AP treatment, whereas healthy volunteers (without 4-AP treatment) were studied only once. Whole blood samples of 2.5 mL were drawn at 0 (before 1 g of oral acetaminophen) and at 15, 30, 45, 60, 75, 90, 105 and 120 min postdose. Acetaminophen concentration in plasma was determined by high-pressure liquid chromatography.
  
  
  RESULTS
  Treatment with 4-AP significantly delayed stomach emptying in patients with chronic SCI, considering the significant decreasing of acetaminophen absorption (t paired test, p <0.05). This effect did not correlate either to the level or ASIA score of the injury (linear regression correlation analysis, r(2) = 0.003 and 0.015, respectively). No significant differences were observed by comparing data of patients before 4-AP treatment with healthy volunteers.
  
  
  CONCLUSIONS
  4-AP intake in patients with chronic spinal cord injury significantly slowed gastric emptying regardless of level and ASIA score of the injury.
authors.affiliation: Medical Research Unit for Neurological Diseases, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City, Mexico. igrjalvao@yahoo.com
authors.forename: Israel
authors.initials: I
authors.lastname: Grijalva
authors.forename: Gabriel
authors.initials: G
authors.lastname: Guízar-Sahagún
authors.forename: Delia
authors.initials: D
authors.lastname: Rodríguez-Pacheco
authors.forename: Carlos
authors.initials: C
authors.lastname: Francisco-Argüelles
authors.forename: Gilberto
authors.initials: G
authors.lastname: Castañeda-Hernández
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Palma-Aguirre
mesh_terms: D015761:4-Aminopyridine / Q000009:adverse effects* / Q000627:therapeutic use; D000328:Adult; D004415:Dyspepsia / Q000139:chemically induced / Q000175:diagnosis*; D005260:Female; D005746:Gastric Emptying / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D026902:Potassium Channel Blockers / Q000009:adverse effects* / Q000627:therapeutic use; D013119:Spinal Cord Injuries / Q000188:drug therapy*
chemical_list: D026902:Potassium Channel Blockers; D015761:4-Aminopyridine