We have previously demonstrated that mitogen-activated protein kinase phosphatase 1, Mkp1, is expressed in the developing and rat adult substantia nigra and striatum, where it promotes the growth of nigral dopaminergic neurons. Mkp1 may therefore have therapeutic potential for Parkinson's disease. In the present study, we have assessed the expression of Mkp1 and TH in the substantia nigra and s...

In the present study, changes in the neuronal activity of serotonergic neurons in the dorsal raphe nucleus (DRN) and the effect of the selective 5-HT1A receptor antagonist WAY-100635 in a rat model of Parkinson’s disease (PD) were investigated by using extracellular single unit recording. Rat model of PD was produced by microinjection of 6-hydroxydopamine (6-OHDA) into the substantia nigra pars...

Iron may play an important role in Parkinson's disease (PD) since it can induce oxidative stress-dependent neurodegeneration. The objective of this study was to determine whether the iron chelator, phytic acid (IP6) can protect against 6-hydroxydopamine- (6-OHDA-) induced apoptosis in immortalized rat mesencephalic dopaminergic cells under normal and iron-excess conditions. Caspase-3 activity w...

Parkinson's disease (PD) involves an initial loss of striatal dopaminergic terminals evolving into a degeneration of dopaminergic neurons in the substantia nigra (SN), which can be modeled by 6-hydroxydopamine (6-OHDA) administration. Since ATP is a danger signal acting through its P2X7 receptors (P2X7R), we now tested if a blood-brain barrier-permeable P2X7R antagonist, Brilliant Blue G (BBG),...

Astragalus membranaceus is a medicinal plant traditionally used in China for a variety of conditions, including inflammatory and neural diseases. Astragalus polysaccharides are shown to reduce the adverse effect of levodopa which is used to treat Parkinson's disease (PD). However, the neuroprotective effect of Astragalus polysaccharides per se in PD is lacking. Using Caenorhabditis elegans mode...

These experiments were designed to test Kasamatsu and Pettigrew's (1979, 1983, and see below) hypothesis that plasticity in the visual cortex requires cortical norepinephrine (NE). Kittens were treated with various doses of intraventricular 6-hydroxydopamine (6-OHDA) or vehicle solution. Cortical NE content was measured with high-performance liquid chromatography with electrochemical detection....

Nonimmunosuppressant immunophilin ligands have been found previously to stimulate neurite growth in culture and to promote regeneration of peripheral and central nerve fibers in vivo. To further characterize the effectiveness of these ligands, we have investigated the effect of the immunophilin ligand GPI-1046 in 6-hydroxydopamine (6-OHDA)-lesioned rats. In unlesioned rats, tetanic stimulation ...

Parkinson's disease (PD) patients and the 6-hydroxydopamine (6-OHDA) lesioned rat model share blink abnormalities. In view of the evolutionarily conserved organization of blinking, characterization of blink reflex circuits in rodents may elucidate the neural mechanisms of PD reflex abnormalities. We examine the extent of this shared pattern of blink abnormalities by measuring blink reflex excit...

OBJECTIVE High frequency stimulation (HFS) of the subthalamic nucleus (STN) is recognized as an effective treatment of advanced Parkinson's disease. However, the neurochemical basis of its effects remains unknown. The aim of this study is to investigate the effects of STN HFS in intact and 6-hydroxydopamine (6-OHDA)-lesioned hemiparkinsonian rat model on changes of principal neurotransmitters, ...

In postnatal tissues, angiogenesis occurs in nontumoral conditions on appropriate stimuli. In the nervous tissue, hypoxia, neural graft, increased neural function, and synaptic activity are associated with neoangiogenesis. We have investigated the occurrence of neoangiogenesis in the superior cervical ganglia (scg) of newborn rats treated for 8--21 days with 6-hydroxy-dopamine (6-OHDA), nerve g...