Metabolism of exogenous histamine in rainbow trout (Oncorhynchus mykiss)

Abstract

Information on the metabolism of exogenous histamine in fish is of much concern regarding the effect of dietary histamine on fish. Histamine catabolic enzymes, diamine oxidase and histamine N-methyl transferase were measured in the tissues of rainbow trout. Diamine oxidase was detected in the stomach, pylorus caeca and intestine. Histamine N-methyl transferase was detected only in the liver.A change in the contents of histamine and its metabolites was observed in the tissues of rainbow trout after oral administration of histamine. A large amount of imidazole acetic acid was observed in the serum, kidney, liver and muscle. On the other hand, 1-methyl histamine was detected only in the liver. Histamine and its metabolites, imidazole acetic acid and 1-methyl histamine were metabolized and diminished within 48 hr in all tissues.These results showed that histamine was metabolized by two metabolic routes in rainbow trout. One is the main pathway producing imidazole acetic acid by intestinal diamine oxidase and the other is the complementary pathway producing 1-methyl histamine by liver N-methyl-transferase.

Separation assay of histamine and its metabolites in biological specimens

“…The determination in the urinary excretion of HA and MHA in normal humans by a similar procedure was also reported by Saito et al (1994). The isoindole derivatives are also detectable by on-line oxidation using EC detection (Harsing et al, 1986a,b;Borycz et al, 2000;Han and Vohra, 1991;Shiozaki et al, 2003;Lozeva et al, 1999). The HA content of the nervous system in the fruit fly, Drosophila melanogaster, which is a widely used model in neuroscience research, was determined by the LC method coupled with pre-column OPA/2-ME derivatization and EC detection (Borycz et al, 2000).…”

“…However, N π -MHA was not found in the biological samples. Many similar methods by pre-column derivatization utilizing OPA/thiol have been reported (Ronnberg et al, 1984;Harsing et al, 1986a;Devalia et al, 1985;Siegel et al, 1990a,b;Robert et al, 1983;Shiozaki et al, 2003). OPA/thiol is also adaptable as the reagent for post-column derivatization.…”

“…OPA/thiol and DBD-F) was excellent for the selective and sensitive detection of target molecules. HA and MHA, possessing a primary amine in the structure, were labeled with OPA and a thiol [2-mercaptoethanol (2-ME; Borycz et al, 2000) or Nacetylcysteine (NAC; Shiozaki et al, 2003)] before (pre-column derivatization) and after the LC separation (post-column derivatization). The simultaneous determination of HA, MHA and N π -MHA in human urine and rat brain was carried out by reversed-phase LC after derivatization with OPA and 2-ME (Tsuruta et al, 1981).…”

“…The HA contents of the glandular stomach and forestomach in Wistar rats were determined by the CL system (Alam et al, 1995). The enzyme activity of the diamine oxidase and histamine-N-methyltransferase in the tissues of rainbow trout were also indirectly measured based upon the determination of HA and MHA (Shiozaki et al, 2003).…”

Identification of oyster-derived hypotensive peptide acting as angiotensin-I-converting enzyme inhibitor

“…The pellet was lysed with 0.5% Triton X-100 in 50 mM Tris-HCl (pH 7.9). Serum was prepared as previously described [18]. ACE activities of the aorta lysates and serum were measured as described above.…”