The aim of the present study was to determine hypoxia-induced changes in the long-term expression of tyrosine hydroxylase (TH) mRNA and the steady-state dopamine (DA) levels in rat mesencephalic cell cultures. The cultures were exposed to hypoxia during the early developmental period, and DA content and TH mRNA expression were determined on day in vitro (DIV) 14. Hypoxic exposure of 5-day-old c...

Tyrosine hydroxylase activity of synaptosomes isolated from rat brain was examined. A modified tritium-displacement assay was used, which allowed the measurement of tyrosine hydroxylase activity without the addition of either inhibitors of the metabolism of the hydroxylated products or added exogenous cofactor. The enzyme activity was strongly inhibited by the addition of exogenous catecholamin...

background: free radical formation and oxidative stress might play an important role in the pathogenesis of parkinson's disease (pd). in vitro data indicate that neuromelanin (nm) pigment is formed the excess cytosolic catecholamine that is not accumulated into synaptic vesicles via the vesicular monoamine transporter 2 (vmat2). we designed this study to investigate the neuroprotective eff...

Tyrosine hydroxylase is synthesized de nouo in rat superior cervical ganglia in organ culture. The differential rate of synthesis is not increased significantly by the addition of nerve growth factor to the culture. Prior administration of nerve growth factor in vim. however, leads to an augmented synthesis of tyrosine hydroxylase in ganglia subsequently cultured in vitro. The differential rate...

Loss-of-function DJ-1 mutations have been linked to autosomal recessive early-onset Parikinsonism. However, the putative function of DJ-1 is not completely understood. Previous studies indicate that DJ-1 overexpression results in upregulation of the tyrosine hydroxylase gene. The mechanism by which DJ-1 affects tyrosine hydroxylase expression remains elusive. In the present study, we show that ...

Tyrosine hydroxylase is synthesized de novo in rat superior cervical ganglia in organ culture. The differential rate of synthesis is not increased significantly by the addition of nerve growth factor to the culture. Prior administration of nerve growth factor in vivo, however, leads to an augmented synthesis of tyrosine hydroxylase in ganglia subsequently cultured in vitro. The differential rat...

The ventral tegmental area (catecholaminergic group A10) is a midbrain region characterized by concentrated dopaminergic immunoreactivity. Previous studies in pigeons show that the ventral tegmental area provides a robust projection to the hippocampal formation and to the medial column of the inferior olive. However, the distribution, morphology, and neurochemical content of the neurons that co...

Parkinson's disease (PD) is a common neurodegenerative disorder with no cure. Astragalus membranaceus used in Chinese culture as food supplement to boost immunity. The present study aimed explore the neuroprotective effects of total flavonoids extracted from A. (TFA) and their protective mechanisms. TFA offered neuroprotection against 1-methyl-4-phenyl-1,2,3,6 -tetrahydropyridine (MPT...

Antibodies to tyrosine hydroxylase, dopamine beta-hydroxylase and phenylethanolamine N-methyltransferase were used in an immunocytochemical examination of catecholamines in the cochlea. In cryostat sections, tyrosine hydroxylase and dopamine beta-hydroxylase-like immunoreactivities fibers were seen in the modiolus that did not extend to the organ of Corti. These corresponded to blood vessel-ass...

Drosophila melanogaster is a valuable model organism to study aging and pathological degenerative processes in the nervous system. The advantages of the fly as an experimental system include its genetic tractability, short life span and the possibility to observe and quantitatively analyze complex behaviors. The expression of disease-linked genes in specific neuronal populations of the Drosophi...