Sexual Dimorphism in N-Acetyltransferase Activity, Hydroxyindole-O-methyltransferase Activity, and Melatonin Content in the Harderian Gland of Syrian Hamsters: Changes following Gonadectomy

Armando Menendez-Pelaez, Russel J. Reiter, Juan M. Guerrero, Manuel Puig-Domingo, Kimberly A. Howes

Research output: Contribution to journalArticle

41 Scopus citations


The activities of N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT) and the melatonin content of the Harderian glands of intact and gonadectomized male and female Syrian hamsters were studied. NAT activity in intact male Harderian glands was twice that of the female. Prepubertal or adult castrated males exhibited a decrease in NAT activity to a level comparable to that seen in the female. Testosterone implants in the castrated males led to a recovery of the original male NAT levels. Intact male hamsters had very low levels of Harderian HIOMT activity and melatonin content in comparison with the glands of the females. Prepubertal gonadectomy but not castration of adult males raised the levels of HIOMT activity and the melatonin content to those of the females. Bilateral ovariectomy had no effect on melatonin content, NAT activity, or HIOMT activity in the female hamster Harderian gland.

Original languageEnglish (US)
Pages (from-to)287-291
Number of pages5
JournalProceedings of the Society for Experimental Biology and Medicine
Issue number3
Publication statusPublished - Mar 1988


ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

Cite this