Digoxin-like factors in herbal teas.
Forty-six commercially packaged teas and 78 teas prepared from purchased herbs were assayed for digoxin-like factors (DLF) by their crossreactivity with digoxin antibody (immuno-crossreactive DLF) and by their inhibition of ouabain binding to membrane Na,K-ATPase (NKA inhibitory DLF). Three packaged teas and 3 herbs gave NKA inhibitory DLF values > 30 micrograms digoxin equivalents/cup. Two packaged teas and 3 herbs gave immuno-crossreactive DLF values > .050 micrograms digoxin equivalent/cup. One herb, pleurisy root, had a crossreactive DLF value of 187 micrograms/cup and NKA inhibitory DLF equivalent to 3658 micrograms/cup. Plasma digoxin-like factors were measured after ingestion of the 3 commercially packaged herbal teas with highest values for NKA inhibitory DLF. After ingestion of each of the 3 teas, plasma NKA inhibitory DLF increase, in one case more than 100-fold. Two teas produced a measurable increase in plasma immuno-crossreactive DLF after ingestion. Some digoxin-like factors in human plasma may have a dietary source.
Longerich
L
L
Faculty of Medicine, Memorial University of Newfoundland, St. John's, Canada.
Johnson
E
E
Gault
M H
MH
D001628:Beverages; D003429:Cross Reactions; D004077:Digoxin / Q000276:immunology / Q000493:pharmacokinetics / Q000494:pharmacology*; D006801:Humans; D007408:Intestinal Absorption; D019684:Magnoliopsida / Q000737:chemistry*; D008297:Male; D008875:Middle Aged; D010042:Ouabain / Q000378:metabolism; D010936:Plant Extracts / Q000276:immunology / Q000493:pharmacokinetics / Q000494:pharmacology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors / Q000378:metabolism; D013662:Tea / Q000737:chemistry*
D010936:Plant Extracts; D013662:Tea; D010042:Ouabain; D004077:Digoxin; D000254:Sodium-Potassium-Exchanging ATPase