title: The alpha (α)-glucosidase inhibitor, acarbose, attenuates the blood pressure and splanchnic blood flow responses to intraduodenal sucrose in older adults.
abstract: BACKGROUND
  Postprandial hypotension is an important problem in the elderly and may be triggered by the increase in splanchnic blood flow induced by a meal. Acarbose attenuates the fall in blood pressure (BP) induced by oral sucrose and may be useful in the management of postprandial hypotension. It is not known whether the effect of acarbose on postprandial BP reflects slowing of gastric emptying and/or carbohydrate absorption nor whether acarbose affects splanchnic blood flow. We examined the effects of intraduodenal (ID) acarbose on the BP, heart rate, superior mesenteric artery (SMA) flow, and glycemic and insulin responses to ID sucrose in older participants--this approach excluded any "gastric" effect of acarbose.
  
  
  METHODS
  Eight healthy participants (four male and four female, age 66-77 years) received an ID infusion of sucrose (~6 kcal/min), with or without acarbose (100 mg), over 60 minutes. BP, heart rate, SMA flow, blood glucose, and serum insulin were measured.
  
  
  RESULTS
  Acarbose markedly attenuated the falls in systolic (p < .01) and diastolic (p < .05) BP and rises in heart rate (p < .05), SMA flow (p < .05), blood glucose (p < .01), and serum insulin (p < .05). The maximum fall in systolic BP and peak SMA flow was inversely related on the control day (r(2) = -.53, p < .05) but not with acarbose (r(2) = .03, p = .70).
  
  
  CONCLUSIONS
  We conclude that in healthy older participants receiving ID sucrose, (a) acarbose markedly attenuates the hypotensive response by slowing carbohydrate absorption and attenuating the rise in splanchnic blood flow and (b) the fall in BP is related to the concomitant increase in SMA flow.
authors.affiliation: Discipline of Medicine, Royal Adelaide Hospital, University of Adelaide, North Terrace, Adelaide, SA 5000, Australia.
authors.forename: Diana
authors.initials: D
authors.lastname: Gentilcore
authors.forename: Lora
authors.initials: L
authors.lastname: Vanis
authors.forename: Judith M
authors.initials: JM
authors.lastname: Wishart
authors.forename: Christopher K
authors.initials: CK
authors.lastname: Rayner
authors.forename: Michael
authors.initials: M
authors.lastname: Horowitz
authors.forename: Karen L
authors.initials: KL
authors.lastname: Jones
mesh_terms: D000042:Absorption / Q000187:drug effects; D020909:Acarbose / Q000008:administration & dosage*; D000368:Aged; D000375:Aging; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure / Q000187:drug effects*; D050260:Carbohydrate Metabolism / Q000187:drug effects; D004386:Duodenum; D004791:Enzyme Inhibitors / Q000008:administration & dosage*; D005260:Female; D065089:Glycoside Hydrolase Inhibitors; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007022:Hypotension / Q000209:etiology / Q000517:prevention & control; D007263:Infusions, Parenteral; D007328:Insulin / Q000097:blood; D008297:Male; D017538:Mesenteric Artery, Superior / Q000187:drug effects / Q000502:physiology; D019518:Postprandial Period; D012039:Regional Blood Flow / Q000187:drug effects; D013152:Splanchnic Circulation / Q000187:drug effects*; D013395:Sucrose / Q000008:administration & dosage*
chemical_list: D001786:Blood Glucose; D004791:Enzyme Inhibitors; D065089:Glycoside Hydrolase Inhibitors; D007328:Insulin; D013395:Sucrose; D020909:Acarbose