Inhibition of 11 beta-hydroxylase activity was observed to be due to the interaction of adriamycin with adrenal cortex mitochondria. The inhibition of the enzyme was uncompetitive, with an apparent Ki of 100 microM, and was dependent upon the concentration of the drug and the time of incubation. Adriamycin increased the oxygen consumption of these mitochondria. EPR studies showed that adriamycin was reduced to a free radical semiquinone which served to shuttle electrons to oxygen, leading to an impairment in the reduction of cytochrome P450. It is suggested this may be the mechanism for the inhibitory effect of the drug on 11 beta-hydroxylase activity.
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http://dx.doi.org/10.1016/0003-9861(84)90227-3 | DOI Listing |
J Mol Model
January 2025
Laboratorio de Química Teórica Computacional (QTC), Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, 7820436, Santiago de Chile, Chile.
Context: Dopamine -monooxygenase (D M) is an essential enzyme in the organism that regioselectively converts dopamine into R-norepinephrine, the key step of the reaction, studied in this paper, is a hydrogen atom transfer (HAT) from dopamine to a superoxo complex on D M, forming a hydroperoxo intermediate and dopamine radical. It was found that the formation of a hydrogen bond between dopamine and the D M catalyst strengthens the substrate-enzyme interaction and facilitates the HAT which takes place selectively to give the desired enantiomeric form of the product. Six reactions leading to the hydroperoxo intermediate were analyzed in detail using theoretical and computational tools in order to identify the most probable reaction mechanism.
View Article and Find Full Text PDFPulm Circ
October 2024
Department of Research BIAL, Portela & Cª, S.A. Coronado S. Romão e S. Mamede Portugal.
Activation of the sympathetic nervous system is observed in pulmonary arterial hypertension patients. This study investigates whether inhibiting the conversion of dopamine into noradrenaline by dopamine -hydroxylase (DH) inhibition with BIA 21-5337 improved right ventricular (RV) function or remodeling in pressure overload-induced RV failure. RV failure was induced in male Wistar rats by pulmonary trunk banding (PTB).
View Article and Find Full Text PDFCancer Res
November 2024
St. Jude Children's Research Hospital, Memphis, TN, United States.
Neurosci Lett
November 2024
Laboratory of Veterinary Anatomy and Cell Biology, Faculty of Agriculture, Iwate University, 18-8, Ueda 3-chome, Morioka, Iwate 020-8550, Japan. Electronic address:
The distribution of Fos expression in catecholaminergic neurons with immunoreactivity for dopamine β-hydroxylase (DBH) of the ventrolateral medulla was compared between rats exposed to hypoxia (10 % O), hypercapnia (8 % CO), and hypercapnic hypoxia (8 % CO and 10 % O) for 2 h. Among the experimental groups, hypoxia-exposed rats had more Fos/DBH double-immunoreactive neurons than the control group (20 % O) in the rostral area of the ventrolateral medulla, specifically in the range of + 150 μm to + 2,400 μm from the caudal end of the facial nerve nucleus. On the other hand, Fos/DBH double-immunoreactive neurons were scarcely observed in the ventrolateral medullary region of hypercapnia-exposed rats.
View Article and Find Full Text PDFInt J Mol Sci
September 2024
Modern Vegetable Industry Technology and Germplasm Resource Innovation Team, Northeast Asia Special Germplasm Resource Conservation and Innovation Center Vegetable Breeding Technology Innovation Team, College of Horticulture, Jilin Agricultural University, Changchun 130118, China.
and , members of the Physalis genus, are valued for their delicious and medicinal fruits as well as their different ripened fruit colors-golden for and scarlet for . This study aimed to elucidate the pigment composition and genetic mechanisms during fruit maturation in these species. Fruit samples were collected at four development stages, analyzed using spectrophotometry and high-performance liquid chromatography (HPLC), and complemented with transcriptome sequencing to assess gene expression related to pigment biosynthesis.
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