title: Flow-mediated K(+) secretion in horses intoxicated with lolitrem B (perennial ryegrass staggers).
abstract: OBJECTIVE
  To investigate the effects of lolitrem B intoxication on renal K(+) secretion in response to increased tubular flow rates.
  
  
  METHODS
  Results are derived from a repeated measure pilot study of seven horses fed non-perennial ryegrass feed for a week prior to exposing them to perennial ryegrass seed and hay that contained an average of 2 ppm lolitrem B. At the end of the control and treatment period frusemide (1 mg/kg I/V) was administered and serial fractional excretion of K(+)(FEK(+)) and fractional excretion of Na(+)(FENa(+)) calculated. Baseline concentration of aldosterone in plasma, serum K(+)concentration and feed K(+) concentration were also compared.
  
  
  RESULTS
  Key findings included a reduced change in FEK(+) from 0 to 15 minutes in response to frusemide administration (p=0.022, Wilcoxon signed-rank test) and a reduced baseline concentration of aldosterone in plasma (p=0.022, Wilcoxon signed-rank test) during the treatment period compared with the control.
  
  
  CONCLUSIONS
  Results suggest that lolitrem B intoxication reduced flow-mediated K(+) secretion and interfered with aldosterone production or secretion. However, further investigation is required to validate these findings and to further elucidate the underlying pathophysiology.
  
  
  CONCLUSIONS
  Lolitrem B intoxication in horses may cause disruption to electrolyte handling in addition to neurological deficits.
authors.affiliation: New Bolton Centre, University of Pennsylvania, 382 West Street Road, Kennett Square, Pennsylvania 19384, USA. laurakjohnstone@gmail.com
authors.forename: L K
authors.initials: LK
authors.lastname: Johnstone
authors.forename: I G
authors.initials: IG
authors.lastname: Mayhew
mesh_terms: D000818:Animals; D004232:Diuretics / Q000494:pharmacology; D005260:Female; D005665:Furosemide / Q000494:pharmacology; D006734:Horse Diseases / Q000139:chemically induced* / Q000378:metabolism; D006736:Horses; D026121:Indole Alkaloids; D007668:Kidney / Q000378:metabolism; D007674:Kidney Diseases / Q000139:chemically induced / Q000662:veterinary*; D008129:Lolium / Q000737:chemistry*; D008297:Male; D009183:Mycotoxins / Q000633:toxicity*; D010939:Plant Poisoning / Q000378:metabolism / Q000662:veterinary; D010947:Plants, Toxic / Q000737:chemistry / Q000633:toxicity; D011188:Potassium / Q000378:metabolism*; D012639:Seeds
chemical_list: D004232:Diuretics; D026121:Indole Alkaloids; D009183:Mycotoxins; D005665:Furosemide; C033673:lolitrem B; D011188:Potassium