Melatonin in the Testis of the Cabbage Armyworm, Mamestra brassicae

Toshiaki Shimizu* and Naokuni Takeda Laboratory of Applied Entomology, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183, Japan Department of Biomedical Science, COSMO Research Institute, Gongendo, Satte, Saitama, 340-01, Japan Z. Naturforsch. 53c, 927-931 (1998); received May 14/June 12, 1998 Melatonin, Mamestra brassicae, Testis, HPLC-ECD, Metabolic Pathways, Diapausing Pupae jV-Acetyl-5-methoxytryptamine (melatonin; MEL) was detected in the testis of non-diapausing pupae and in the testis of post-diapause pharate adults of the cab­ bage armyworm, Mamestra brassicae, by use of a threedimensional HPLC system with multiple coulometric electrochemical detectors. Intermediates providing evidence of various metabolic pathways were identified, as follows: tryptophan (TRP) —* 5-hydroxytryptophan (5-HTP) —* 5-hydroxytryptamine (5-HT) —*• ./V-methyl-5-hydroxytryptamine (/V-MET) I—► 5-hydroxyindoleacetic acid (5-HIAA) L yV-acetyl-5-hydroxytryptamine (/V-ACET-5-HT) melatonin (MEL).