Substantia Nigra, Pars Compacta


Adult male Wistar rats with bilateral substantia nigra, pars compacta (SNc) lesion induced by intranigral administration of 0.5 mumol 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were used as a model of early phase Parkinson's disease (PD).  

In order to study neuronal death in Parkinson's disease, neurons of the substantia nigra, pars compacta in rats were exposed to elevated levels of glutamate and decreased levels of energy in vivo and consequences for behavior and neuronal morphology were studied. Thereafter, the cytoarchitecture of the substantia nigra, pars compacta of the brains of these rats was described.The L-THA plus malonate injected rats did not differ in their behavior from carrier injected rats, except for rigidity: their scores were higher than that of carrier and L-THA injected rats (P < 0.05), while L-THA injected rats did not differ from carrier injected controls. Observations on cresyl violet sections revealed, that, although many neurons with a shrunken nucleolus and faintly stained cytoplasm were present in both L-THA and L-THA plus malonate treated rats, the ventral edge of the substantia nigra, pars compacta containing modified cells was longer in L-THA plus malonate than in L-THA injected rats (P < 0.05). This indicates, that a minimum amount of damage to neurons in the ventral part of the substantia nigra, pars compacta might be required for the expression of rigidity..  

tyrosine hydroxylase-positive) neurons of the rat substantia nigra, pars compacta.  

The effects of neurotensin and neurotensin analogues on dopamine neurones were studied in an in vitro slice preparation of rat substantia nigra, pars compacta using extracellular and intracellular recording techniques.  

Electrical stimulation of the substantia nigra, pars compacta, of albino rats while they were learning a simple foot shock task of withdrawal and response suppression disrupted retention of that task 24 hours after original learning. Stimulation through electrodes in the medial lemniscus, red nucleus, or brainstem regions surrounding the substantia nigra, pars compacta, was also ineffective. Posttrial stimulation in the substantia nigra, pars compacta, but not in adjacent structures, also disrupted retention performance..  


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