title: Effect of continuous intravenous infusion of carteolol chloride on tissue blood flow in rabbit optic nerve head.
abstract: OBJECTIVE
  To investigate the effect of an intravenous infusion of carteolol on tissue blood flow in the optic nerve head (ONH) of rabbits.
  
  
  METHODS
  Rabbits received either a 3-week topical instillation, or a single intravenous injection (10, 20, 30 microg/kg) or a continuous intravenous injection (2.5, 5, 20, 40, 80 microg/kg per hour) of carteolol. The plasma carteolol level was determined by the gas chromatography negative-ion chemical ionization mass spectrometric method. The ONH blood flow was determined by the hydrogen clearance method.
  
  
  RESULTS
  The plasma level of carteolol after a 3-week instillation was 5.55 ng/mL, and a continuous intravenous injection (5 microg/kg per hour) led to approximately the same plasma level. The continuous intravenous infusion of 5 microg/kg per hour of carteolol significantly increased the ONH blood flow compared to the controls from 30 minutes to 2 hours after the beginning of the infusion (n = 10). The mean blood pressure and intraocular pressure (n = 6) were not significantly changed during the continuous intravenous infusion of carteolol.
  
  
  CONCLUSIONS
  These results suggest that the plasma carteolol level in rabbits after long-term instillation can increase the ONH blood flow. We conclude that the increase resulted from a reduction in the vascular resistance in the ONH.
authors.affiliation: Department of Ophthalmology, Osaka Medical College, Takatsuki, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sugiyama
authors.forename: I
authors.initials: I
authors.lastname: Azuma
authors.forename: M
authors.initials: M
authors.lastname: Araie
authors.forename: S
authors.initials: S
authors.lastname: Fujisawa
authors.forename: H
authors.initials: H
authors.lastname: Urashima
authors.forename: M
authors.initials: M
authors.lastname: Nagasawa
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage* / Q000097:blood; D000818:Animals; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D002354:Carteolol / Q000008:administration & dosage* / Q000097:blood; D008401:Gas Chromatography-Mass Spectrometry; D007262:Infusions, Intravenous; D007429:Intraocular Pressure / Q000187:drug effects; D008297:Male; D009898:Optic Disk / Q000098:blood supply* / Q000187:drug effects; D011817:Rabbits; D012212:Rheology
chemical_list: D000319:Adrenergic beta-Antagonists; D002354:Carteolol