Catecholestrogens inhibit dopamine methylation in the gonadotrops of the African catfish,Clarias gariepinus
- 1 July 1989
- journal article
- Published by Springer Nature in Fish Physiology and Biochemistry
- Vol. 6 (4) , 207-212
- https://doi.org/10.1007/bf01875023
Abstract
Isolated gonadotrops of the African catfish,Clarias gariepinus, were incubated with dopamine (DA) and/or catecholestrone and the activity of the enzyme catechol-O-methyltransferase (COMT) was determined by measuring the methylated products. From the apparent Km values for DA and catecholestrone of 0.4–1.3 μM and 17.9–25.2 μM respectively, it was concluded that catecholestrone is a better substrate for the enzyme COMT, compared to DA. Moreover, the methylation of DA is inhibited by comparatively low concentrations of catecholestrone.Keywords
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