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E Bronzetti

Publications and source records attributed to E Bronzetti.

87 records · Page 5Linked to original sources
PubMedDate not supplied

Lactate dehydrogenase, succinate dehydrogenase and nucleotide tetrazolium reductase histochemical activities in the mesentric arteries and arterioles of young and old rats.

Age-related changes of the metabolic characteristics of large, medium and small brances of the rat superior mesenteric artery were investigated in young (4 month) and old (25 month) male Wistar rats, using enzyme histochemical techniques. The following enzymatic activities were examined: lactate dehydrogenase (LDH) and succinate dehydrogenase (SDH); NADPH(2)-tetrazolium reductase (NADPHD) and NADH(2)-tetrazolium reductase (NADHD). The intensity of enzymatic reactions within the tunica media of the large, medium and small branches and within the tunica intima of the large and medium branches of the artery was assessed microphotometrically. In young rats the reactivity of enzymes investigated is similar in both the tunica media and the intima with the exception of SDH which reacts stronger in the media than in the intima. LDH and NADHD displayed the most intense reaction whereas SDH reaction was less intense. In old rats LDH and NADPHD reactivity decreased, SDH reactivity increased in the intima of large and medium branches; and SDH increased in the media of large branches. The possibility is discussed that an impaired endothelial function may represent one of the most consistent phenomena of aging of the superior mesenteric artery.

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Age-related changes of glutamate dehydrogenase in the rat hippocampus: an enzyme histochemical study.

Enzyme histochemical techniques associated with microphotometry were used to evaluate the reactivity of glutamate dehydrogenase (GDH) in the hippocampus of young (3 month) adult (12 month) and old (26 month) male Sprague-Dawley rats. In young rats the highest level of enzymatic reactivity was found in the stratum oriens of the CA-1-CA-4 fields followed in descending order by the molecular layer of fascia dentata, and by the layer of mossy fibers. In all the layers investigated GDH reactivity was higher in adult that in young rats. The older animals exhibited lower GDH reactivity than adult rats in almost all of the layers and higher enzymatic reactivity than in young rats in the stratum oriens of the CA-1-CA-4 fields. The hippocampus is known to be involved in the acquisition of two-way avoidance learning and is thought to utilize glutamate as one of its main neurotransmitters. These data suggest a possible relationship between hippocampal glutamatergic transmission and impairment of acquisition of avoidance learning occurring with age. Moreover, the possibility that a decreased glutamate catabolism occurring in old rats may contribute to the neuronal loss described in the hippocampus of aged rats is discussed.

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Age-related changes of the noradrenergic innervation of the uterine vasculature: a fluorescence histochemical study.

Age-related changes in the density of the noradrenergic perivascular plexus supplying the uterine artery and its intrauterine branches were studied in rats 4, 12 and 24 months old using the glyoxylic acid fluorescence technique. Moreover, uterine noradrenaline levels were determined by means of high pressure liquid chromatography with electrochemical detection. No changes in the density of noradrenergic innervation or in uterine noradrenaline levels were noticeable in 12 month in comparison with 4 month rats. In contrast, a significant decrease in the density of the noradrenergic perivascular plexus of uterine artery and of its intrauterine branches as well as decrease in noradrenaline concentrations of uterine horns and cervix were observed in 24 month rats. The above findings indicate an age-related impairment of uterine noradrenergic innervation.

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Nucleus basalis magnocellularis lesions impair mossy fiber system in rat hippocampus: a quantitative histochemical and ultrastructural study.

Lesions of the nucleus basalis magnocellularis (NBM) cause depletion of choline acetyltransferase (ChAT) in the cerebral cortex and behavioral changes consisting of impaired ability to learn avoidance tasks. Since hippocampal mossy fibers (MF) are involved in the elaboration of passive avoidance responses, we analyzed MF by means of Timm's histochemical technique and electron microscopy, to find out whether monolateral lesions of NBM had any effect on MF system. NBM-lesioned rats, 3 weeks after lesioning, showed a significant and progressive decrease in the density of Timm staining as well as significant changes of the morphology of synapic boutons of the MF. These results suggest that, although NBM does not send direct projections to the hippocampus, lesions of this nucleus may have a neurodegenerative effect on the intrahippocampal pathway involved in avoidance responses.

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Age-related anatomical changes in the rat hippocampus: retardation by choline alfoscerate treatment.

The age-related anatomical changes in the rat hippocampus were evaluated in male Sprague-Dawley rats of 3 (young), 12 (mature) and 24 (aged) months by counting the number of nerve cells in the CA1 and CA3 fields and in the dentate gyrus and by measuring the density of Nissl bodies in the cytoplasm of the pyramidal and granule neurons of the above areas. Moreover, the effect of 3 months choline alfoscerate treatment on the anatomical parameters examined was evaluated. The number of pyramidal neurons of the CA1 field and of granule neurons of the dentate gyrus was not significantly changed between young and mature animals, but it was decreased in aged rats. The number of pyramidal neurons of the CA3 field showed a progressive age-dependent reduction. The density of Nissl bodies was the highest in the cytoplasm of pyramidal or granule neurons in mature rats followed in descending order by young and aged animals. Choline alfoscerate treatment counteracted the age-related loss of nerve cells in the 3 hippocampal portions examined and slow-drown the decrease of Nissl bodies in the cytoplasm of pyramidal or of granule neurons in the hippocampus. The significance of changes induced by choline alfoscerate in the hippocampus of aged rats and the possible mechanism of action of the compound are discussed.

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Changes in the intensity of sulfide staining in fronto-parietal cortex of the rat following nucleus basalis magnocellularis lesions: possible relevance to Alzheimer's disease.

The sulfide staining technique, known also as neo-Timm staining, predominantly stains associational fibres arising from cortical interneurons located primarily in the neuropil of layers I-III of the rat cerebral cortex. The density of these fibres, considered to have a possible role in cognitive and mnemonic processes, has been demonstrated to be related to the density of zinc-containing presynaptic buttons in the cerebral cortex. The unilateral injection of ibotenic acid into the nucleus basalis magnocellularis (NBM) resulted in no changes in the density of sulfide staining in the first 3 weeks after neurotoxin injection and in a significant loss of sulfide staining in the neuropil of cortical layers I-III 4 weeks after NBM lesion in the fronto-parietal cortex ipsilaterally to the lesion. These data suggest that unilateral lesioning of the NMB may cause changes of chemo-specific zinc-containing intracortical pathways. Moreover, they indicate that, in a manner similar to that described in the brain of Alzheimer's disease patients, NBM-lesioned rats show a decrease of zinc tissue stores in the fronto-parietal cortex.

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Effect of choline alfoscerate treatment on changes in rat hippocampus mossy fibres induced by monolateral lesioning of the nucleus basalis magnocellularis.

We have recently demonstrated that monolateral lesions of the Nucleus Basalis Magnocellularis (NBM), which is a nucleus sending cholinergic projections to the fronto-parietal cortex, cause a loss in the intensity of Timm staining in the intrahippocampal pathway of mossy fibres (MF). Moreover, these lesions induce ultrastructural changes consistent with the occurrence of degeneration of presynaptic buttons of MF. The present study was designed to quantify the effects of NBM lesioning on the morphology of the presynaptic buttons of MF. Moreover the effects of 4-week choline alfoscerate (alphaGFC) treatment on the density of Timm staining and on the ultrastructure of presynaptic buttons of MF were assessed, alphaGFC, which was given at an oral daily dose of 100 mg/kg, is a precursor in the biosynthesis of several brain phospholipids which increases the availability of choline in the nervous tissue. Monolateral lesions of NBM cause, 4 weeks after lesioning, a significant decrease in the intensity of Timm staining in the MF area accompanied by a loss of about 23% of presynaptic buttons of MF. Moreover about 40% of presynaptic buttons of MF show an impaired morphology. alphaGFC administration restored the intensity of Timm staining in the MF area. In alphaGFC-treated rats, the loss of presynaptic buttons and the number of impaired buttons were reduced to about 12% and 27%, respectively in comparison with non-treated animals. These results confirm and extend our previous observations indicative of the occurrence of transneuronal degenerations in the MF of the hippocampus after monolateral NBM lesioning. Moreover these findings show that alphaGFC treatment is able to counter in part these degenerative changes.

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Influence of ipsilateral lesions of the nucleus basalis magnocellularis and of choline alphoscerate treatment on histochemically reactive zinc stores and on the ultrastructure of the rat frontal cortex.

The influence of ipsilateral lesions of the nucleus basalis magnocellularis (NBM) and of choline alphoscerate treatment on histochemically reactive zinc stores and on the ultrastructure of the neuropil of layer III of the frontal cortex were investigated in the rat. In control animals a dark-brown staining was developed in the neuropil of layers I-III of the frontal cortex. Lesions of the right NBM caused a marked reduction in the density of sulphide-silver staining in the right frontal cortex 4 weeks post lesion. Moreover, changes in the morphology and in the density of synaptic buttons in the neuropil of layer III of the cerebral cortex were also noticeable. Concomitant treatment for 4 weeks with choline alphoscerate restored the density of sulphide-silver staining in the right frontal cortex and countered in part changes of synaptic buttons of the neuropil of layer III of the frontal cortex. These findings suggest that the loss of cerebrocortical histochemically reactive zinc stores occurring in NBM-lesioned rats is due to the alterations of synaptic contacts in the frontal cortex and that treatment with choline alphoscerate may counter these degenerative changes.

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The noradrenergic innervation of spinal cord blood vessels in old rats.

The density and pattern of the sympathetic noradrenergic innervation of the extramedullary and intramedullary blood vessels of the spinal cord was studied in 3-, 12- and 25-month-old male Wistar rats using combined catecholamine histofluorescence and quantitative image analysis techniques. The study of innervation of intramedullary vessels was accomplished in spinal cord-transected rats to avoid the interference of descending spinal monoamine fibres in the observations. No age-related changes in the density of noradrenergic innervation of the anterior spinal artery or of sympathetic fibres associated with spinal cord blood vessels occurred. These results suggest that unlike perivascular noradrenergic nerves supplying the cerebrovascular tree, the sympathetic innervation of spinal cord blood vessels does not undergo age-dependent changes. It cannot be excluded that the lesser vulnerability of the spinal compared to the cerebral vascular tree to certain kinds of age-related diseases, may depend on the unchanged sympathetic trophic regulation of spinal vessels with age.

Adrenergic Fibers↗
PubMedDate not supplied

In situ hybridization and immunocytochemistry of alpha1-adrenoceptors in human peripheral blood lymphocytes.

1 alpha1-Adrenoceptor subtypes were investigated in cytospin centrifuged preparations of human peripheral blood lymphocytes by in situ hybridization and immunocytochemistry. 2 In situ hybridization cytochemistry revealed alpha1A-, alpha1B-, and alpha1D-receptor mRNA in human peripheral blood lymphocytes. Lymphocytes hybridized for alpha1A receptor subtype represented approximately 30% of total lymphocytes, those hybridized for alpha1Beta- and alpha1D-receptor subtypes averaged 42 and 25% of total lymphocytes, respectively. 3 Cytospin centrifuged lymphocytes exposed to anti-alpha1A-, alpha1Beta- or alpha1D-receptor protein antibodies, developed specific immunostaining. Approximately 27% of total lymphocytes were immunoreactive for alpha1A-receptor protein, 40% displayed alpha1B-receptor protein immunoreactivity and 22% alpha1D-receptor protein immunoreactivity. Analysis of percentages as well as of lymphocyte morphology of in situ hybridized and immunolabelled lymphocytes suggests the co-expression of mRNA receptor signal and protein receptor immunostaining in the same lymphocyte. 4 The demonstration of both alpha1-adrenoceptor mRNA and receptor protein subtypes suggests that alpha1-adrenoceptors may have a role in regulating lymphocyte function. 5 The possibility of demonstrating receptor protein immunoreactivity in a small amount of blood, such as that required for preparing cytospin-centrifuged lymphocytes, may stimulate research to evaluate the role of these receptors in lymphocytes and to establish if assessment of lymphocyte alpha1-adrenoceptors may represent a marker of their status in health and disease.

Adult↗
PubMedDate not supplied

Dopamine receptor immunohistochemistry in the rat choroid plexus.

1. Earlier studies have demonstrated a high density of dopamine D1-like receptor binding in the choroid plexus by light microscope autoradiography, but the dopaminergic specificity of this binding was questioned. 2. In this study the localization of dopamine receptor subtypes was investigated in the rat choroid plexus by Western blot analysis and immunohistochemistry using antibodies raised against dopamine D1-D5 receptor protein. 3. Western blot analysis revealed reactivity with immune bands of approximately 50 and 51 KDa corresponding to dopamine D1 and D5 receptors, respectively. Dopamine D1-like (D1 and D5) receptor protein immunoreactivity insensitive to superior cervical ganglionectomy was located in smooth muscle of choroid arteries and to a larger extent within choroid plexus epithelium. 4. Western blot analysis revealed reactivity with immune bands of approximately 53 KDa and 40-42 KDa corresponding to dopamine D2 and D4 receptors, respectively, and no dopamine D3 receptor reactivity. Dopamine D2-like receptor protein immunoreactivity displayed a distribution similar to that of tyrosine-hydroxylase (TH)-immunoreactive sympathetic fibres and disappeared after superior cervical ganglionectomy. It consisted in the expression of dopamine D2 and to a lesser extent of D4 receptor protein immunoreactivity perivascularly and associated with choroid epithelium. No D3 receptor protein immunoreactivity was found in rat choroid plexus. 5. The above results indicate that rat choroid plexus expresses dopamine receptor protein, being dopamine D1-like receptors predominant in epithelium and arterial smooth muscle and D2-like receptors in sympathetic nerve fibres supplying choroid plexus epithelium and vasculature. 6. These findings suggests that dopamine receptors with a different anatomical localization may modulate production of cerebrospinal fluid.

Animals↗
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Neurotrophins and neurotrophin receptors in human pulmonary arteries.

The localization of neurotrophins (NTs) and NT receptors was analyzed in sections of human extra- and intrapulmonary arteries by Western blot analysis and immunohistochemistry. In extrapulmonary branches of human pulmonary artery, NT and NT receptor immunoreactivity was located in the tunica intima, within endothelium, in the tunica media, within smooth muscle and in the tunica adventitia. In different sized intrapulmonary arteries, NT and NT receptor immunoreactivity was observed primarily in the tunica adventitia. A faint NT and NT receptor immunoreactivity was observed in the tunica media of large-sized branches of intrapulmonary arteries, but not within medium- or small-sized intrapulmonary vessels or in tunica intima of different sized intrapulmonary arteries. These findings suggest that NTs may have a role in the control of vascular responses in the pulmonary system acting as local paracrine or autocrine mediators. The possible relevance of the NT system in human pulmonary vasculature identified in this study is discussed.

Adolescent↗
PubMedDate not supplied

Dopamine D1-like receptor subtypes in the rat kidney: a microanatomical study.

The microanatomical localization of dopamine D1A and D1B receptor subtypes was investigated in sections of rat kidney using immunohistochemicals techniques with antidopamine D1A and D1B receptor antibodies. Microanatomical analysis was limited to the various components of nephron. Dopamine D1A receptor immunoreactivity was found primarily in the epithelium of loop of nephron (loop of Henle) and of collecting tubules. A less intense immunoreactivity was observed within proximal and distal convoluted tubules as well as in juxtaglomerular complex. Dopamine D1B receptor immunoreactivity was found primarily in proximal and distal convoluted tubules and within the juxtaglomerular complex. A less intense immunoreactivity was observed in the epithelium of collecting tubules followed by the loop of nephron. The demonstration of the localization of dopamine D1A and D1B, receptor subtypes along the nephron may contribute to better define their significance in physiological and pathological conditions.

Animals↗
PubMedDate not supplied

[Inflammatory pseudotumor of the bladder: etiopathologic and clinical features].

The Authors present a case of inflammatory pseudotumour (IPT) of the urinary bladder occurring in a 57-year-old female patient, who was referred to our department with haematuria, stranguria and hypogastric pain. Ultrasonographic, radiological and endoscopic examinations showed a sessile, ulcerated, easily bleeding bladder formation; urinary cytology revealed no atypical transitional cells. Abdomino-pelvic computed tomography analysis showed thickening of the bladder walls and infiltration of the perivesical fat. Histopathologically, the formation was indicated as an inflammatory pseudotumour (IPT) of the bladder. The patient underwent TURB (transurethral resection of the bladder) and was discharged clinically healed on postoperative day 4. A one-year follow up revealed no evidence of recurrence. On the basis of their experience and a thorough review of the literature review, the Authors discuss the clinico-pathological features of IPT of the bladder and the possible factors involved in the malignant transformation of IPT. In conclusion, the benign nature of the lesion is stressed.

Female↗