No abstract available.
Models, Animal* ; Oxidopamine* ; Parkinsonian Disorders*

No abstract available.
Animals ; Neurons* ; Oxidopamine* ; Rats* ; Substantia Nigra*

OBJECTIVE: In this experimental study, authors evaluated the effect of repeated graft of the fetal midbrain cells on rat model of hemiparkinsonism. MATERIALS AND METHODS: Following injection of the 6-hydroxydopamine into striatum, we examined the behavior (turning response to amphetamine and apomorphine) at 2, 4 and 8 weeks. Their turning behavior persisted until 8 weeks after lesion making. Only those with turning behavior of more than average 6.2turns/minute by amphetamine test were selected for transplantation. Three different methods of transplantation were assigned into three groups and compared with each other to evaluate their efficiencies in improving behavioral responses. In first method, the volume of the transplanted cells were equivalent to that of one fetal midbrain. The volume of the transplanted cells were twice as much as that of one fetal midbrain in a group with second method. The last group consisted of repeated transplantation. Here, we transplanted the same amount of fetal midbrain cells as the in group 2 with two divided doses in one month interval. RESULTS: The second and third group improved from amphetamine test significantly(p<0.05), whereas first group failed to show any significant improvement from same test. The results from second and third group were not significantly different from each other. CONCLUSION: This results suggest that transplantation of two volumes of the fetal midbrain is needed to improve the turning behavior of this model of parkinsonism. This volume can be tansplanted at once or it may be transplanted in two divided volumes with time interval, with similar effect.
Amphetamine ; Animals ; Mesencephalon ; Models, Animal* ; Oxidopamine* ; Parkinsonian Disorders ; Rats* ; Transplants*

OBJECTIVE: The aim of this study was to investigate voluntary wheel running behavior in the unilateral 6-hydroxydopamine (6-OHDA) rat model. METHODS: Male Sprague-Dawley rats were assigned to 2 groups : 6-OHDA group (n=17) and control group (n=8). The unilateral 6-OHDA rat model was induced by injection of 6-OHDA into unilateral medial forebrain bundle using a stereotaxic instrument. Voluntary wheel running activity was assessed per day in successfully lesioned rats (n=10) and control rats. Each behavioral test lasted an hour. The following parameters were investigated during behavioral tests : the number of running bouts, the distance moved in the wheel, average peak speed in running bouts and average duration from the running start to the peak speed. RESULTS: The number of running bouts and the distance moved in the wheel were significantly decreased in successfully lesioned rats compared with control rats. In addition, average peak speed in running bouts was decreased, and average duration from the running start to the peak speed was increased in lesioned animals, which might indicate motor deficits in these rats. These behavioral changes were still observed 42 days after lesion. CONCLUSION: Voluntary wheel running behavior is impaired in the unilateral 6-OHDA rat model and may represent a useful tool to quantify motor deficits in this model.
Animals ; Humans ; Male ; Medial Forebrain Bundle ; Models, Animal* ; Oxidopamine* ; Parkinson Disease* ; Rats ; Rats, Sprague-Dawley ; Running*

BACKGROUND: Apomorphine-induced rotational behavior of unilateral 6-hydroxydopamine (OHDA) lesioned rat is widely used to develop anti-Parkinsonian treatments including drugs, neuroprotective therapy, and neural graft. Time course of changes in rotational behavior after lesioning, however, has not been fully elucidated. The aim of this study was to observe the chronological changes in the rotational response and to find the optimal period when this model is used for investigation of various therapies. METHODS: 6-OHDA was stereotaxically delivered to the unilateral substantia nigra in 13 rats. Rotational responses to apomorphine administrations were counted in the rotomotor on 2, 4, 8, 12, and 14 weeks after lesioning. RESULTS: The total turns for two hours increased continuously up to eight weeks, and then plateaued. CONCLUSIONS: Apomorphine-induced rotations increase until eight weeks after 6-OHDA lesioning. Therefore, this Parkinsonian model should be used at least eight weeks after lesioning. Even though priming was not excluded as an explanation in the experiment, we reason that progressive degeneration of dopaminergic neurons may explain the chronological changes in rotational behavior.
Animals ; Apomorphine* ; Dopaminergic Neurons ; Neuroprotective Agents ; Oxidopamine* ; Rats* ; Substantia Nigra ; Transplants

PURPOSE: Thioredoxin is an endogenous antioxidant. It regulates the activities of transcriptional factors such as NF-kB(nuclear factor kappa B)and AP-1(activator protein-1) and it increases the synthesis of cytokines, preventing cellular proliferation and apoptosis. The aim of this study was to clarify the role of thioredoxin on apoptosis-inducing neuronal cell injury. We investigated the protective effects of thioredoxin against apoptosis-inducing neuronal cell injury through intracellular mechanism by 6-hydroxydopamine and serum deprivation. METHODS: PC 12 cells were cultured in RPMI 1640 media containing 10% fetal calf serum and subcultured in 96-well plates. Each well contained 30,000 cells. Cells were treated with hydrogen peroxide, diamide or 6-hydroxydopamine 30 minutes after thioredoxin treatment and then incubated for 24 hours. Cytotoxicity and cellular viability were assessed by measuring lactate dehydrogenase(LDH) release and MTT reduction. RESULTS: Thioredoxin increased cytotoxicity of PC cells treated with 6-hydroxydopamine by increasing LDH release and decreasing MTT reduction. In the serum deprivation condition, thioredoxin increased cytotoxicity of PC cells by increasing LDH release. CONCLUSION: Thioredoxin potentiates oxidative injury through intracellular mechanisms by 6-hydroxydopamine and serum deprivation instead of protecting. The cytotoxicity of thioredoxin may be mediated by decreasing the activity of NF-kB, which has been reported recently to protect against cellular apoptosis. Evidence suppors that the cytotoxic effect was not increased in the presence of serum in this study. Therefore, we found that the antioxidant effects of thioredoxin depended on mechanisms of injuries.
Antioxidants ; Apoptosis ; Cell Proliferation ; Cytokines ; Diamide ; Hydrogen Peroxide ; Lactic Acid ; Neurons* ; NF-kappa B ; Oxidopamine ; Thioredoxins*

Fetal dopaminergic or nondopaminergic cortical tissues were implanted directly into the denervated striatum of partial lesioned rat parkinsonian models. After transplantation, at rats were behaviourally tested with apomorphine and sacrificed for tyrosine hydroxylase immunohistochemical stain. The results of this study are summarized as follows : 1) Of 45 rats partially lesioned with 6-hydroxydopamine, 17 rats(37.8%) met a criteria(a minimum of 4 times/min to apomorphine-induced rotation test) of the rat parkinsonian model. 2) Eight weeks after transplantation of the fetal dopaminergic tissues into the striatum of the rat parkinsonian model, transplanted dopaminergic cells were found to be alive. Also reinnervated dopaminergic fibers were found in the previously denervated striatum. And the behavioural study suggested that the transplantation of the fetal dopaminergic neurons had influenced on the apomorphine-induced rotation. 3) Eight weeks after transplantation of the fetal nondopaminergic tissues into the striatum of the rat parkinsonian model, dopaminergic cells were not found in the previously denervated striatum. However, reinnervation of the dopaminergic fibers were found in the preciously denervated striatum. However, reinnervation of the dopaminergic fibers were found in the previously denervated striatum as well as the reduction of the apomorphine-induced rotation compared to the pregraft state. The major finding of this study support a trophic hypothesis for the mechanism of recovery in response to fetal dopaminergic or nondopaminergic tissue. The author conclude that fetal nondopaminergic tissue also had some beneficial effect in reducing apomorphine-induced rotational asymmetry probably by promoting recovery or sprouting of remaining dopaminergic fibers at the previously denervated striatum of the rat parkinsonian model.
Animals ; Apomorphine ; Dopaminergic Neurons ; Oxidopamine ; Rats* ; Tissue Transplantation* ; Transplantation ; Transplants* ; Tyrosine 3-Monooxygenase

An apomorphine-induced rotational test has been used in the evaluation of rat parkinsonian models lesioned with neurotoxin 6-hydroxydopamine (6-OHDA). Previous parkinsonian rat models have generally been characterized by unilateral destruction of both nigrosriatal pathway and mesolimbic pathway using 6-OHDA. The authors created partial lesioned rat parkinsonian models using 6-OHDA in which there is destruction of the dopaminergic nigrostriatal pathway and sparing of the mesolimbic pathway. Rats with unilateral lesions of the substantia nigra pars compacta(SNpc) were tested for rotational asymmetry using a cylindrical rotometer device with flat bottom(diameter, 30.5cm) after administration of apomorphine. After completion of the rotation test, the animals were sacrificed and their brains were immunolabeled for tyrosine hydroxylase(TH). Analysis of anatomical and behavioral data suggests that the pattern of rotation(pivotal rotation) is more reliable index for loss of TH-immunoreactive neurons in lesioned SNpc than the total number of rotational responses to apomorphine. The exact cause of the abnormal ipsiversive rotation which some rats showed is unclear. Further research should be pursued to explain this finding.
Animals ; Apomorphine ; Brain ; Models, Animal ; Neurons ; Oxidopamine* ; Parkinson Disease ; Rats* ; Substantia Nigra ; Tyrosine

OBJECTIVE: The purpose of this study is to investigate the effect of ipsilateral subthalamic nucleus(STN) lesioning on the spontaneous behavioral changes and the alteration of neuronal activities of deep cerebral nuclei in the rat parkinsonian model with 6-hydroxydopamine(6-OHDA). METHODS: To identify the spontaneous behavioral changes, apomorphine-induced rotational test and forepaw adjusting step were performed. We subsequently investigated the alteration of neuronal activities in the substantia nigra pars reticulata(SNpr) and globus pallidus(GP), in order to compare them with the behavioral changes in rat parkinsonian models. RESULTS: The STN lesioning in the rat parkinsonian model clearly improved behavioral changes. Compared to the normal control rats, rat PD models exhibited a significant increase in mean firing rates and the percentage of bursting neurons in the STN and SNpr. In the STN-lesioned rat PD models, mean firing rates and the percentage of bursting neurons in the SNpr were reduced and those in the GP increased. CONCLUSION: STN lesioning induced behavior improvement in rat parkinsonian models seems to be consistent with the surgical outcomes of the STN stimulation therapy in advanced Parkinsonn's disease(PD). The alteration of the neuronal activities in the SNpr and GP suggests that these sites are responsible for the improvement of parkinsonian motor symptoms observed following STN lesioning in rat parkinsonian models. The significance of bursting activity in the SNpr and GP remains obscure. Further study is necessary to elucidate the pathophysiological mechanism of PD.
Animals ; Fires ; Globus Pallidus ; Kainic Acid* ; Neurons* ; Oxidopamine* ; Parkinson Disease ; Rats* ; Substantia Nigra ; Subthalamic Nucleus

Unilateral obstruction or injury to the vas deferens can result in significant injury to the contralateral testicle. Although various pathways have been proposed, the mechanism of contralateral testicular deterioration remains controversial. The present animal study was performed to evaluate the effects of unilateral vasectomy on ipsilateral and contralateral testicular histology and fertility in rats that were chemically sympathectomized neonatally. The study comprised 40 male albino rats: 20 received a placebo and the other 20 underwent chemical sympathectomy neonatally. When 60 days old, each group of 20 rats was divided into two groups that underwent either a sham operation or an operation to create unilateral left vasectomy. Eight weeks after surgery, each male rat was housed with two known fertile female rats for 25 days, and then their testes were harvested. Mean seminiferous tubular diameters (MSTD) and mean testicular biopsy scores (MTBS) were determined for each testis. Although MSTD and MTBS were not significantly different between groups, chemical sympathectomy prevented the decrease in total fertility rates of the rats with unilateral left vasectomy in our study. Prevention of this decrease by chemical sympathectomy suggests that the sympathetic nervous system may play a role in the testicular degeneration associated with vasectomy.
Animals ; Female ; Fertility/*drug effects ; Male ; Oxidopamine/toxicity ; Rats ; *Sympathectomy, Chemical ; Testis/drug effects/*pathology ; *Vasectomy