Elevation of plasma dopamine-β-hydroxylase activity during insulin-induced hypoglycemia in man

Résumé Nous avons étudié l'activité de la dopamine--hydroxylase du plasma humain. Elle a été remarquablement accure par l'administration de grandes quantités d'insuline. Les corrélations entre cette activité et celle des systèmes nerveux sympathiques sont également discutées.     

Adrenal dopamine-β-hydroxylase activity: 24-hour rhythmicity and evidence for pineal control

Summary Adrenal medullary dopamine--hydroxylase activity was found in male rats to have a 24-hour rhythm, with an approximately 6-fold increase at about the time of the onset of darkness. This nocturnal rise in enzyme activity did not occur when lights were kept on, nor did it occur in animals that had been pinealectomized.Supported in part by grants from the Ford Foundation (No. 630-05050A), National Institutes of Health (No. HD-03352) and National Institute of Mental Health (No. MH-25019) USPHS.     

Erythrocyte catechol-O-methyltransferase and plasma dopamine-β-hydroxylase in human umbilical cord blood

Summary Plasma dopamine--hydroxylase enzymatic activity and immunoreactive protein levels in human umbilical cord blood are only about 2% as great as values in the blood of older subjects. Erythrocyte catechol-O-methyltransferase activity levels in umbilical cord blood are very similar to those in the blood of adult subjects.This work was supported in part by NIH grants NS 11014 and HL 17487-1. Dr Weinshilboum is an Established Investigator of the American Heart Association. We thank Luanne Wussow and the physicians and nurses of the Department of Obstetrics and Gynecology of the Mayo Clinic for their assitance with these studies.     

Dopamine-β-hydroxylase,adrenaline, noradrenaline and dopamine in the venous blood of adrenal gland of man: A comparison with levels in the periphery of the circulation

Summary In 10 human subjects plasma dopamine--hydroxylase activity was found in the adrenal vein blood to be as high as in the periphery of the circulation. Adrenaline concentration in the adrenal vein blood was in the mean 170 times, noradrenaline concentration 11 times and dopamine concentration little higher than levels in the periphery.This study was supported by the Deutsche Forschungsgemeinschaft.