Histamine N-methyltransferase preparation used for histamine assay contains endogenous histamine.
D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D006632:Histamine / Q000032:analysis*; D006637:Histamine N-Methyltransferase / Q000032:analysis*; D007668:Kidney / Q000201:enzymology; D008297:Male; D008780:Methyltransferases / Q000032:analysis*; D051381:Rats; D011919:Rats, Inbred Strains
D006632:Histamine; D008780:Methyltransferases; D006637:Histamine N-Methyltransferase