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E C Hirsch

Publications and source records attributed to E C Hirsch.

At least 145 records · Page 8Linked to original sources
PubMed1991

Mesencephalic cholinergic nuclei in progressive supranuclear palsy.

Using an antibody against choline acetyltransferase (ChAT), mesencephalic cholinergic cell nuclei were studied in autopsy material from 3 cases of progressive supranuclear palsy (PSP) and 4 controls. ChAT-immunoreactive neurons were quantified in sections that spanned the rostrocaudal extent of each nucleus. In PSP, there was a significant decrease in the number of neurons with detectable immunoreactivity for ChAT in and adjacent to the central gray substance in the following nuclei: the nucleus of Edinger-Westphal (69%); the rostral interstitial nucleus of the medial longitudinal fasciculus (97%); the interstitial nucleus of Cajal (78%). A cell loss was also evident in a group of neurons found in the deep layers of the superior colliculus (93%). In contrast, the estimated number of ChAT-immunoreactive cell bodies in cranial nerves III and IV, in the mesencephalic reticular formation, and in the parabigeminal nucleus was not different from that of controls. The results are compatible with the notion that, in PSP, there is a regionally selective destruction of cholinergic neurons.

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PubMed1991

Progressive supranuclear palsy: loss of choline-acetyltransferase-like immunoreactive neurons in the pontine reticular formation.

We performed a quantitative immunocytochemical study using a polyclonal antibody directed against choline acetyltransferase (ChAT) in the lower pontine reticular formation in four control subjects and three patients with progressive supranuclear palsy (PSP). In the normal brains, there was detectable ChAT-like immunoreactivity in the nucleus papillioformis, a precerebellar reticular nucleus, and in the nucleus pontis centralis caudalis. In PSP patients, the mean estimated total number of ChAT-like immunoreactive cells was 54% of controls in nucleus papillioformis and 40% of controls in nucleus pontis centralis caudalis. The demonstration of ChAT-like immunoreactivity in nucleus papillioformis is consistent with studies suggesting an extrinsic cholinergic innervation of the cerebellar cortex. Loss of cholinergic cells in nucleus pontis centralis caudalis that corresponds largely to the paramedian pontine reticular formation may be related to disturbances of horizontal saccades in PSP patients.

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PubMed1990

Compartmental ordering of cholinergic innervation in the mediodorsal nucleus of the thalamus in human brain.

The cholinergic innervation of the mediodorsal (MD) nucleus of the thalamus was visualized immunohistochemically in human brain postmortem, using an antibody against human choline acetyltransferase (ChAT). The ChAT staining of the MD nucleus was more intense than in the surrounding thalamic nuclei but weaker than that of the striatum. No ChAT-positive cell bodies were detected. The ChAT-positive neuropil was unevenly distributed, with patches of dense immunoreactivity contrasting with a weaker surrounding matrix. In adjoining sections stained for ChAT immunoreactivity and for acetylcholinesterase (AChE) activity, the zones enriched in ChAT-immunostained neuropil corresponded to AChE-rich regions. The three-dimensional reconstruction of the richest zone in AChE/ChAT activity evidenced a cylindrical organization throughout the rostrocaudal axis of the MD nucleus. Counts of ChAT-positive varicosities confirmed an inhomogeneous distribution; the density of varicosities was 30% higher in ChAT-rich regions than in surrounding matrix. These findings suggest that the activity of intrinsic neurons within the nucleus may be differentially regulated by cholinergic systems.

Acetylcholinesterase↗
PubMed1990

Does adrenal graft enhance recovery of dopaminergic neurons in Parkinson's disease?

A 54-year-old man with a 5-year history of Parkinson's disease was treated with and autograft of adrenal medulla into the right caudate nucleus and died 4 months after surgery. Postmortem examination revealed that the graft was necrotic. It consisted mainly of reticulin and collagen fibrosis without catecholaminergic cell bodies identified either by immunohistochemistry or by in situ hybridization with labeled human tyrosine hydroxylase (TH) cDNA probe. Sparse TH-immunoreactive fibers, which did not stain for dopamine-beta-hydroxylase (DBH), ran through the graft. In contrast, intense staining for these catecholaminergic markers was found in the untransplanted adrenal medulla. Densely packed TH-positive, DHB-negative fibers were found in a restricted zone of the host striatum at the periphery of the graft. This effect was selective since the density of other neurons was not modified. The present study describes an additional patient in whom adrenal medulla autotransplantation failed to improve the parkinsonian disability. It suggests, however, that adrenal medulla grafts may stimulate the sprouting of striatal dopaminergic fibers in a limited zone of the grafted striatum.

Adrenal Medulla↗
PubMed1990

Decreased tyrosine hydroxylase messenger RNA in the surviving dopamine neurons of the substantia nigra in Parkinson's disease: an in situ hybridization study.

Parkinson's disease is associated with a massive loss in melanized dopaminergic neurons in the substantia nigra resulting in a severe striatal dopaminergic denervation. The hyperactivity which develops in the remaining striatal dopaminergic terminals may be related to an increased rate of tyrosine hydroxylation. This could be related to changes in the level of expression of the gene coding for tyrosine hydroxylase. Thus, the detection of tyrosine hydroxylase messenger RNA was looked for at cellular levels by in situ hybridization histochemistry. Image analysis shows that the hybridization signal was significantly reduced in the surviving neurons when compared to control. The subnormal tyrosine hydroxylase messenger RNA content may express a change in level of tyrosine hydroxylase gene transcription, possibly in relation to sustained suffering of the neurons still present at late stages of the disease.

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PubMed1990

Microtopography of D1 dopaminergic binding sites in the human substantia nigra: an autoradiographic study.

The autoradiographic distribution of D1 dopaminergic binding sites was studied in the human ventral mesencephalon using the D1 antagonist [3H]SCH 23390. [3H]SCH 23390 binding was characterized by a single class of sites with a Kd of 2.5 nM and a Bmax of 31 fmol/mg of tissue. The density of [3H]SCH 23390 binding sites was high in the substantia nigra, moderate in the ventral tegmental area and low in the peri- and retrorubral field (catecholaminergic region A8). Binding densities were similar in pars compacta and pars reticulata of the substantia nigra, except for a peak value of high [3H]SCH 23390 in the pars reticulata, at a level just ventral to a zone of hyperdensity of melanized dopaminergic neurons in the pars compacta. The anatomical organization of the human ventral mesencephalon was analysed on adjacent sections stained for acetylcholinesterase histochemistry and tyrosine hydroxylase, substance P, dynorphin B, somatostatin and methionine-enkephalin immunohistochemistry, respectively. The similarity in distribution of [3H]SCH 23390 binding sites and substance P or dynorphin B immunoreactivity suggests that D1 binding sites are mainly located on the striatonigral projections. In accordance with these results: (1) the density of [3H]SCH 23390 binding sites was reduced in the substantia nigra of a patient with Huntington's chorea, a disease associated with a degeneration of striatonigral neurons; (2) the density of [3H]SCH 23390 binding sites was unaffected in the substantia nigra of a patient with Parkinson's disease, a disorder characterized by a marked loss in nigral tyrosine hydroxylase-positive neurons. [3H]SCH 23390 binding sites showed a characteristic, heterogeneous distribution within the human ventral mesencephalon, confirming data obtained in other species. The preferential localization of D1 dopamine receptors on striatonigral projections in human brain suggests that pharmacological manipulation of these receptors modulates the activity of striatonigral pathways, thereby affecting the various outputs of the nigral complex.

Acetylcholinesterase↗
PubMed1990

Catecholaminergic systems in the medulla oblongata in parkinsonian syndromes: a quantitative immunohistochemical study in Parkinson's disease, progressive supranuclear palsy, and striatonigral degeneration.

We investigated tyrosine-hydroxylase (TH)-immunoreactive neurons in the medulla oblongata corresponding to the A1 and A2 cell groups in autopsy tissue of patients with Parkinson's disease (PD) (n = 3), progressive supranuclear palsy (PSP) (n = 3), striatonigral degeneration (SND) (n = 2), and in controls (n = 4). The estimated total number of TH-positive neurons in the A1 and the A2 regions was normal in PD and PSP patients. The sparing of medullary catecholaminergic cells in PD and PSP may be related to their minor degree of melanization and the possibility that intermediate compounds associated with the oxidative catabolism of norepinephrine and epinephrine may be less cytotoxic than those generated by degradation of dopamine. Patients with SND showed a marked loss of TH-immunoreactive cells in the A1 and the A2 groups, which may contribute to the impairment of vasomotor control characteristic of the disease.

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PubMed1990

The nigrostriatal system in Parkinson's disease.

Patterns of dopaminergic cell loss in the midbrain and patterns of mesostriatal fiber loss in the caudate nucleus and putamen are described for cases of idiopathic Parkinson's disease. Neither cell loss nor fiber loss is homogeneous. In the midbrain, quantitative analysis points to a selective vulnerability of neurons in the most heavily pigmented dopaminergic cell groups. In the striatum, a dorsolateral-to-ventromedial gradient of loss appears to characterize both the caudate nucleus and the putamen. These patterns of loss and sparing have implications both for analysis of the clinical symptoms of Parkinson's disease and for study of the etiology of this disease.

Animals↗
PubMed1989

Localization of copper-zinc superoxide dismutase mRNA in human hippocampus by in situ hybridization.

The cellular localization of copper-zinc superoxide dismutase (CuZn SOD) mRNA was determined in the human hippocampus by in situ hybridization with a 35S-labelled DNA probe complementary to human CuZn SOD mRNA. A positive hybridization signal was detected in pyramidal cell layers CA1-CA4 of Ammon's horn (CA), pyramidal cells of subiculum and in the granule cells of the dentate gyrus. The fact that CuZn SOD gene expression is important in neurones which are preferentially vulnerable in neurodegenerative processes such as Alzheimer's disease, suggests a role played by oxygen free radicals in the mechanism of nerve cell death.

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PubMed1989

Striosomes and extrastriosomal matrix contain different amounts of immunoreactive choline acetyltransferase in the human striatum.

Cholinergic neuropil and cell bodies were identified in the human striatum by immunohistochemistry carried out with a polyclonal antibody raised against choline acetyltransferase (ChAT). The cholinergic neuropil was not uniformly distributed in the striatum, and especially in the caudate nucleus ChAT-poor zones corresponding to acetylcholinesterase (AChE)-poor striosomes were identified. Striosomal organization of ChAT-positive neuropil was also detected in striatal tissue from patients who had suffered parkinsonian and choreic disorders.

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PubMed1989

Selective loss of cholinergic neurons in the ventral striatum of patients with Alzheimer disease.

Cholinergic neurons were studied by immunohistochemistry with an antiserum against human choline acetyltransferase in the caudate nucleus, putamen, and ventral striatum (including the nucleus accumbens) of three patients with Alzheimer disease and three control subjects. Immunoreactive cell bodies were mapped and counted. In the ventral striatum of patients with Alzheimer disease, a 60% decrease in the number of cholinergic neurons was observed, whereas in the caudate nucleus and putamen values for control subjects and patients were similar. To determine whether all neurons in the ventral striatum were affected, neuropeptide Y-containing neurons were also immunostained, mapped, and counted. The number of these neurons was the same in control subjects and patients with Alzheimer disease, indicating that neuronal loss is not generalized in the ventral striatum and may be specific to the cholinergic population.

Acetylcholinesterase↗
PubMed1989

Selective vulnerability of pigmented dopaminergic neurons in Parkinson's disease.

From a neuropathological point, the diagnosis of Parkinson's disease is confirmed by a neuronal cell loss and the presence of Lewy bodies in the substantia nigra. In Parkinson's disease, the precise type of nigral neuron which degenerate still remains unknown. Are all types of neuron similarly injured, are only subpopulations of neurons vulnerable? In an attempt to answer the question, a qualitative and quantitative analysis of the distribution of dopaminergic cells, as identified by immunohistochemistry with a specific antibody against tyrosine hydroxylase, was performed in the ventral mesencephalon of control subjects and patients who died with a clinical diagnosis of Parkinson's disease. In control brains, two types of catecholaminergic neurons were evidenced; some contain visible-neuromelanin, others do not. In patients with Parkinson's disease, the tyrosine hydroxylase positive cells which contained the pigment were the most vulnerable.

Humans↗
PubMed1987

Differences in tyrosine hydroxylase-like immunoreactivity characterize the mesostriatal innervation of striosomes and extrastriosomal matrix at maturity.

Tyrosine hydroxylase [TyrOHase, tyrosine 3-monooxygenase, L-tyrosine, tetrahydropteridine:oxygen oxidoreductase (2-hydroxylating), EC 1.14.16.2] is the rate-limiting enzyme in the synthetic pathway of catecholamines and is expressed by neurons containing dopamine, norepinephrine, and epinephrine. TyrOHase is present in high concentrations in the caudate nucleus and putamen, where nearly all of it is contained in axons of the dopaminergic mesostriatal pathways. We have employed three different polyclonal antibodies directed against TyrOHase, one tested here for specificity by two-dimensional gel electrophoresis, to reexamine the anatomic distribution of fibers expressing TyrOHase-like immunoreactivity in the striatum of mature human, monkey, and cat brains. The findings suggest that this distribution is distinctly inhomogeneous. The macroscopic compartments known as striosomes have low TyrOHase-like immunoreactivity relative to the surrounding extrastriosomal matrix. These observations add to evidence that dopaminergic modulation of neural processing in the mature striatum is organized in accordance with striosomal architecture and suggest that part of the mechanism for such differentiation may involve presynaptic differences in enzymatic regulation of dopamine content in and out of striosomes.

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PubMed1987

Neuronal loss in the pedunculopontine tegmental nucleus in Parkinson disease and in progressive supranuclear palsy.

In the brains of humans and other mammals, there are two principal groups of cholinergic nuclei aside from those forming the cranial motor nuclei. One group lies in the forebrain and includes the nucleus basalis of Meynert. The second group lies in the hindbrain and includes the nucleus tegmenti pedunculopontinus (NPP), identified by Mesulam et al. [Mesulam, M.-M., Mufson, E. J., Wainer, B. H. & Levey, A. I. (1983) Neuroscience 10, 1185-1201] as cholinergic cell group Ch5. The basal forebrain cholinergic cell groups, which innervate widespread areas of the neocortex, undergo degeneration in Alzheimer disease and also in parkinsonism associated with dementia. We here report that the hindbrain NPP Ch5 cell group, thought to innervate many nuclei of the extrapyramidal motor system, the superior colliculus, and the substantia innominata, undergoes degeneration in idiopathic Parkinson disease and in the parkinsonian syndrome of progressive supranuclear palsy. These findings strongly suggest that degeneration in the brainstem in Parkinson disease is not confined to catecholamine-containing neurons, but that cholinergic neurons of the NPP are also vulnerable. The findings further raise the possibility that certain symptoms of Parkinson disease and progressive supranuclear palsy have their genesis in pathology of these cholinergic neurons.

Basal Ganglia↗
PubMedDate not supplied

Neurotrophin receptors and selective loss of cholinergic neurons in Alzheimer disease.

The most consistent neuropathological finding in Alzheimer disease (AD) is the loss of cholinergic neurons of the nucleus basalis of Meynert (NbM). Using immunohistochemistry, we have previously shown that cholinergic neurons located in the ventral striatum were affected, whereas those of the caudate nucleus, putamen, and mesencephalon were spared. Since cholinergic neurons that degenerate in AD are sensitive to NGF and those that are spared are not, it has been hypothesized that the loss of neurotrophins receptors may play a role in the death of cholinergic neurons in AD. Using immunohistochemistry, we have detected the presence of TrkA on most cholinergic neurons from the NbM, on some from those of the striatum, but not on those of the mesencephalon in the human brain. In AD patients, the number of neurons that expressed TrkA was markedly decreased in the NbM very likely as a consequence of cholinergic neuronal loss. In the striatum, despite the loss of high-affinity NGF binding previously reported, no loss of TrkA was observed. Taken together, these results suggest a decreased expression of NGF receptors on the striatal cholinergic neurons in AD. This loss may contribute, when it reaches a crucial threshold, to the death of cholinergic neurons occurring in AD.

Alzheimer Disease↗
PubMedDate not supplied

Biochemistry of Parkinson's disease with special reference to the dopaminergic systems.

The cardinal neurochemical abnormality in Parkinson's disease is the decreased dopamine content in the striatum, resulting from the loss of dopaminergic neurons in the mesencephalon. Precise analysis of the dopaminergic neurons in the midbrain demonstrates, however, that this cell loss is not uniform. Some dopaminergic cell groups are more vulnerable than others. The degree of cell loss is severe in the substantia nigra pars compacta, intermediate in the ventral tegmental area and cell group A8, but nonexistent in the central gray substance. This heterogeneity provides a good paradigm for analyzing the factors implicated in this differential vulnerability. So far, the neurons that degenerate have been shown to contain neuromelanin, high amounts of iron, and no calbindin28K, and to be poorly protected against oxidative stress. By contrast, the neurons that survive in Parkinson's disease are free of neuromelanin, calbindinD28-positive, contain low amounts of iron, and are better protected against oxidative stress. The analysis of the pattern of cell loss in Parkinson's disease may thus bring new clues as to the mechanism of nerve cell death in Parkinson's disease.

Brain Chemistry↗
PubMedDate not supplied

Trk neurotrophin receptors in cholinergic neurons of patients with Alzheimer's disease.

Besides cortical pathology, Alzheimer's disease (AD) is characterized by a loss of cholinergic neurons in the basal forebrain but not in the caudate nucleus, putamen or mesencephalon. Since cholinergic neurons which degenerate in AD are sensitive to nerve growth factor (NGF), a link between NGF sensitivity and the vulnerability of cholinergic neurons has been suspected. Levels of NGF are not altered in patients with AD, however. Thus, cholinergic nerve cell death in AD could not result from a deficiency in NGF receptors. Using sequential immunohistochemistry with antibodies that recognize preferentially TrkA, the specific receptor for NGF, and with antibodies directed against choline acetyltransferase we analyzed the expression of neurotrophin receptors in cholinergic neurons from control and AD brains. TrkA was expressed on cholinergic neurons of the striatum and nucleus basalis of Meynert but not on those of the mesencephalon. In AD patients, the number of neurons expressing TrkA was markedly decreased in the nucleus basalis of Meynert, very likely as a consequence of cholinergic neuronal loss. No loss of TrkA-positive neurons was observed in the striatum. Taken in conjunction with our previously published report of loss of high-affinity NGF binding in the striatum of AD patients, our results suggest a reduced expression of TrkA, the specific receptor for NGF, on striatal cholinergic neurons in AD. The loss of neurotrophin receptors may contribute to the alteration of cholinergic neurons occurring in AD.

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