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R D Ciaranello

Publications and source records attributed to R D Ciaranello.

105 records · Page 6Linked to original sources
PubMed1972

Rapid increase of phenylethanolamine N-methyltransferase by environmental stress in an inbred mouse strains.

The activity of-phenylethanolamine N-methyltransferase in mice of the C57Bl/Ka strain was determined after a 4 degrees C stress. The enzyme activity increased 1.2-fold at the end of 3 hours and by 1.4-fold by the end of 6 hours of the stress. The results are in contrast to those from other species with intact animals in which the enzyme changes only after several days of chronic stress. Cycloheximide prevents the rise in enzyme activity, suggesting the increase may be due to protein synthesis. The increase may provide a model system for studying regulation of catecholamine biosynthetic enzymes.

Adrenal Glands↗
PubMed1972

Genetic variation in activity of enzymes involved in synthesis of catecholamines.

A genetic analysis of differences in adrenal phenylethanolamine N-methyltransferase (EC 2.1.1.X) and tyrosine hydroxylase (EC 1.99.1.X.) and brain tyrosine hydroxylase was performed in three inbred mouse strains. In adrenal glands, the pattern of inheritance of both enzymes was similar; genes carried by the CBA/J strain appeared to be dominant to those of the other strains. The pattern of inheritance of tyrosine hydroxylase activity in adrenals differed from that in the brain. In both tissues, dominant genes appeared to determine intermediate, rather than extreme, levels of enzyme activities.

Adrenal Glands↗
PubMedDate not supplied

Regulation of 5-HT2 and 5-HT1C serotonin receptor levels. Methodology and mechanisms.

Both the 5-hydroxytryptamine2 (5-HT2) and 5-HT1c receptors may be regulated by a large number of endogenous and exogenous factors. The 5-HT2 receptors, for example, may be decreased by acute and chronic treatment with many antipsychotic agents, some antidepressants, and receptor-specific agonists. Similar to the 5-HT2 receptor, the 5-HT1c receptors may be decreased by acute and chronic treatment with the antidepressant mianserin. The 5-HT2 receptors appear to increase during perinatal development and are reported to be elevated in the frontal cortex and hippocampus of victims of suicide; the 5-HT1c receptors display supersensitivity following ablation of serotonergic terminals with 5,7-dihydroxytryptamine. The molecular details responsible for these changes remain unknown, though with the recent cloning of the cDNAs for the 5-HT2 and 5-HT1c receptors the occasion is particularly favorable for mechanistic studies aimed at determining how these alterations occur. Preliminary information suggests that developmentally induced alterations in 5-HT2 and 5-HT1c receptors may be due to transcriptional regulation while changes caused by mianserin treatment might be due to posttranslational processes (e.g., proteolysis, internalization, phosphorylation, covalent alterations). Insights into the molecular means by which 5-HT receptors are regulated could have profound influences on our understanding of pharmacologic, developmental, and psychopathologic processes.

Animals↗