A secretion from cultured bovine chromaffin cells was stimulated to examine the pattern of exocytotic fusion on the plasma membrane. Confocal microscopy revealed that dopamine-beta-hydroxylase immunofluorescence in intact cells stimulated for 20s with the nicotinic agonist 1,1-dimethyl-4-phenylpiperazinium was almost entirely punctate and evenly distributed on the cell surface. The basis for th...

The genetic basis of aggressive behaviour has been examined extensively, including analysis genes encoding neurotransmitters, signalling molecules and regulatory enzymes, as well their synthesis degradation. Dopamine beta-hydroxylase, an enzyme catalysing the conversion dopamine into norepinephrine in synaptic endings, significantly affects modulation emotional states behaviour. aim this study ...

Signaling mechanisms involving Wnt/beta-catenin and sonic hedgehog (Shh) are known to regulate the development of ventral midbrain (vMB) dopamine neurons. However, the interactions between these two mechanisms and how such interactions can be targeted to promote a maximal production of dopamine neurons are not fully understood. Here we show that conditional mouse mutants with region-specific ac...

To evaluate the cholinergic and dopaminergic neuronal interaction in the striatum, the effects of scopolamine, a muscarinic cholinergic antagonist, on the striatal dopaminergic system were evaluated multi-parametrically in the conscious monkey brain using high-resolution positron emission tomography in combination with microdialysis. l-3,4-Dihydroxyphenylalanine (l-[beta-(11)C]DOPA) and 2beta-c...

Dopamine beta-hydroxylase (DbetaH) deficiency is a very rare form of primary autonomic failure characterized by a complete absence of noradrenaline and adrenaline in plasma together with increased dopamine plasma levels. The prevalence of DbetaH deficiency is unknown. Only a limited number of cases with this disease have been reported. DbetaH deficiency is mainly characterized by cardiovascular...

We investigated whether semidehydroascorbic acid was an intermediate in norepinephrine synthesis in chromaffin granules and in electron transfer across the chromaffin granule membrane. Semidehydroascorbic acid was measured in intact granules by electron spin resonance. In the presence of intragranular but not extragranular ascorbic acid, semidehydroascorbic acid was formed within granules in di...

The addition of micromolar quantities of dopamine stimulated ion transport in the isolated rabbit corneal epithelium. This response was blocked by pretreatment with the dopamine antagonist, haloperidol, and by the elimination of Cl- from the bathing solutions. The beta-adrenergic antagonist, timolol, was also a potent inhibitor of the epithelial response to dopamine. The presence of the seroton...

In the subthalamic nucleus (STN) of Parkinson's disease (PD) patients, a pronounced synchronization of oscillatory activity at beta frequencies (15-30 Hz) accompanies movement difficulties. Abnormal beta oscillations and motor symptoms are concomitantly and acutely suppressed by dopaminergic therapies, suggesting that these inappropriate rhythms might also emerge acutely from disrupted dopamine...

Ascorbic acid donates electrons to dopamine beta-monooxygenase during the hydroxylation of dopamine to norepinephrine in vitro. However, the possible role of ascorbic acid in norepinephrine biosynthesis in vivo has not been defined. We therefore investigated the effect of newly accumulated ascorbic acid on catecholamine biosynthesis in cultured bovine adrenal chromaffin cells. Cells supplemente...