BACKGROUND AND PURPOSE Serotonin released from platelets has been suggested as one substance causing the vasospasm following subarachnoid hemorrhage. We studied whether such serotonin is able to constrict pial vessels. METHODS We studied the uptake of serotonin in pial perivascular nerves by immunohistochemistry. We measured the contractile response in rat basilar artery after in vitro incuba...

We have previously described a rat model that responds to repetitive episodic hypoxia (FiO2 nadir 3-5% for 12 seconds every 30 seconds for 7 hr/day for 35 days) with chronic increase in arterial blood pressure. The purpose of the current study was to determine if peripheral sympathetic nervous system denervation blocks this persistent blood pressure elevation. Chemical sympathetic denervation w...

6-Hydroxydopamine administration for 28 days (8 microg/2 microL) reduced the number of tyrosine hydroxylase (TH)-immunopositive neurons to 40.2% in the substantia nigra compared to the intact contralateral side. Dopamine, 3,4-dihydroxyphenylacetic acid, homovanillic acid and norepinephrine levels were reduced to 19.1%, 52.3%, 47.1% and 67.4% in the striatum of 6-hydroxydopamine-lesioned rats co...

6-hydroxydopamine, 1-methyl-4-phenyl-pyridinium (MPP+), and rotenone cause the death of dopaminergic neurons in vitro and in vivo and are widely used to model Parkinson's disease. To identify regulated genes in such models, we performed serial analysis of gene expression on neuronal PC12 cells exposed to 6-hydroxydopamine. This revealed a striking increase in transcripts associated with the unf...

Brain derived neurotrophic factor (BDNF) has been shown to exert trophic effects on dopaminergic neurons against 6-hydroxydopamine (6-OHDA) in young rat. Since the degeneration of substantia nigra dopaminergic neurons that occurs in Parkinson's disease is more often than not confined to elderly individuals, it is of interest to determine whether the effects of BDNF against 6 hydroxydopamine (6-...

Performance maintained by differential-reinforcement-of-low-rate operant schedules has been found to be sensitive to antidepressant drugs. Tricyclic antidepressants, monoamine oxidase inhibitors and atypical antidepressants reduce response rate and increase reinforcement rate under long differential-reinforcement-of-low-rate schedules. In order to study the neurochemical mechanism by which the ...

High-frequency stimulation of the subthalamic nucleus (STN-HFS) is widely used as therapeutic intervention in patients suffering from advanced Parkinson's disease. STN-HFS exerts a powerful modulatory effect on cortical motor control by orthodromic modulation of basal ganglia outflow and via antidromic activation of corticofugal fibers. However, STN-HFS-induced changes of the sensorimotor corte...

Parkinson's disease presents nonmotor complications such as autonomic dysfunction that do not respond to traditional anti-parkinsonian therapies. The lack of established preclinical monkey models of Parkinson's disease with cardiac dysfunction hampers development and testing of new treatments to alleviate or prevent this feature. This study aimed to assess the feasibility of developing a model ...

Parkinson's disease is one of the most common neurodegenerative disorders. There are many documents about the effects of oxidative stress in Parkinson's disease etiology. Angiotensin II activates NADPH dependent oxidases and causes superoxides formation. Peganum harmala L. extract, which has angiotensin converting enzyme (ACE) inhibitory effect, is considered to evaluate oxidative stress inhibi...

Mitragynine is a major alkaloidal constituent of young leaves of Mitragyna speciosa Korth, that is known to exhibit narcotic-like activity. In this study, we investigated the roles of central monoaminergic systems in the antinociceptive action of mitragynine by means of the tail-pinch and hot-plate tests in mice. Mitragynine (1.0-10 micrograms) injected i.c.v. exerted a dose-dependent antinocic...