title: Low-dose transdermal scopolamine decreases blood pressure in mild essential hypertension.
abstract: BACKGROUND
  Increasing cardiovascular parasympathetic nervous activity could have antihypertensive effects. Low-dose transdermal scopolamine increases vagal-cardiac modulation of sinus node and baroreflex sensitivity in healthy subjects and in cardiac patients.
  
  
  OBJECTIVE
  To study the short-term effects of transdermal scopolamine on blood pressure and cardiovascular autonomic control in patients with mild essential hypertension.
  
  
  METHODS
  A randomized, double-blind, placebo-controlled crossover trial with 12 untreated middle-aged [aged 39+/-5 years (mean+/-SD)] patients with mild essential hypertension.
  
  
  METHODS
  We recorded the electrocardiogram, auscultatory sphygmomanometric and continuous photoplethysmographic finger arterial pressure, and spirometry signals with patients supine and 70 degrees tilted during controlled (0.25 Hz) breathing. Cardiovascular autonomic regulation was analyzed with power spectrum analysis of R-R interval and arterial pressure variability and a spontaneous sequence method for baroreflex sensitivity. In addition, a deep-breathing test was performed to assess maximal breathing-related sinus arrhythmia.
  
  
  RESULTS
  Transdermal scopolamine treatment significantly decreased blood pressure both when patients lay supine and when they were in the 70 degrees tilted position. Scopolamine also slowed heart rate and increased baroreflex sensitivity and R-R interval high-frequency variability for both body positionings. In addition, scopolamine accentuated respiratory sinus arrhythmia during deep breathing and blunted the tilt-induced increase in heart rate. Scopolamine did not affect blood pressure variability.
  
  
  CONCLUSIONS
  Transdermal scopolamine decreases arterial pressure, increases baroreflex sensitivity and accentuates vagal-cardiac modulation of sinus node in patients with mild hypertension. Our study supports the hypothesis that increasing cardiovascular parasympathetic activity could have antihypertensive effects in essential hypertension.
authors.affiliation: University of Turku, Finland.
authors.forename: R K
authors.initials: RK
authors.lastname: Vesalainen
authors.forename: T J
authors.initials: TJ
authors.lastname: Kaila
authors.forename: I M
authors.initials: IM
authors.lastname: Kantola
authors.forename: K U
authors.initials: KU
authors.lastname: Tahvanainen
authors.forename: K E
authors.initials: KE
authors.lastname: Juhani Airaksinen
authors.forename: T A
authors.initials: TA
authors.lastname: Kuusela
authors.forename: D L
authors.initials: DL
authors.lastname: Eckberg
mesh_terms: D000279:Administration, Cutaneous; D000328:Adult; D017704:Baroreflex / Q000187:drug effects / Q000502:physiology; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010275:Parasympathetic Nervous System / Q000187:drug effects / Q000503:physiopathology; D010276:Parasympatholytics / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood; D012601:Scopolamine / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood; D012849:Sinoatrial Node / Q000187:drug effects / Q000503:physiopathology; D013990:Tidal Volume / Q000187:drug effects; D014630:Vagus Nerve / Q000187:drug effects / Q000503:physiopathology
chemical_list: D010276:Parasympatholytics; D012601:Scopolamine