gamma-Glutamyl conjugation of 5-hydroxytryptamine (serotonin) in the earthworm (Lumbricus terrestris).
The conversion of 5-hydroxytryptamine to several potential metabolites was examined in the annelid earthworm (Lumbricus terrestris). 5-hydroxytryptamine and some related amines were found to be present in several tissues of the earthworm. Injection of 5-hydroxytryptamine into the body cavity of the earthworm resulted in the production of a gamma-glutamyl conjugate of 5-hydroxytryptamine. Incubations of the anterior nerve cord of the earthworm resulted in the accumulation of considerable amounts of 5-hydroxytryptamine and gamma-glutamyl 5-hydroxytryptamine in the incubation medium. The earthworm did not produce any N-acetyl 5-hydroxytryptamine and only very little 5-hydroxyindoleacetic acid. Experiments involving the injection of radiolabeled 5-hydroxytryptamine or coinjection of radiolabeled glutamic acid with unlabeled 5-hydroxytryptamine into the earthworm resulted in the production of radiolabeled gamma-glutamyl 5-hydroxytryptamine. This work demonstrates that the enzymatic conversion of 5-HT in the earthworm is markedly different from that of vertebrates and insects.
Sloley
B D
BD
Department of Zoology, University of Alberta, Edmonton, Canada.
D000123:Acetyltransferases / Q000378:metabolism*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D008995:Monoamine Oxidase / Q000378:metabolism*; D009835:Oligochaeta / Q000378:metabolism*; D012701:Serotonin / Q000031:analogs & derivatives* / Q000378:metabolism*; D015238:Sulfotransferases / Q000378:metabolism*; D005723:gamma-Glutamyltransferase / Q000378:metabolism*
D012701:Serotonin; C087216:gamma-glutamyl-5-hydroxytryptamine; D008995:Monoamine Oxidase; D000123:Acetyltransferases; D005723:gamma-Glutamyltransferase; D015238:Sulfotransferases