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Biomedical subjects

C Cavallotti

Publications and source records attributed to C Cavallotti.

At least 37 records · Page 2Linked to original sources
PubMed1999

Occurrence of adrenergic nerve fibers and of noradrenaline in thymus gland of juvenile and aged rats.

Adrenergic nerve fibers (ANF) were studied in juvenile, adult and old rats by biochemical and morphological methods and by quantitative analysis of images (QAI). After chemical sympathectomy with neurotoxin 6-OH dopamine, the greater part of ANF disappeared. The whole thymus was drawn in juvenile normal or sympathectomized rats, in adult normal or sympathectomized rats and in old normal or sympathectomized rats. Thymuses from the above-mentioned animals were weighed, measured and dissected. Thymic slices were stained with eosin orange for the detection of the microanatomical details and with Bodian's method for the recognition of the whole nerve fibers. Histofluorescence microscopy was used for staining of ANF while immunofluorescence microscopy was employed for staining of neuropeptide Y (NPY)-like immunoreactivity. Biochemical dosage of proteins and of noradrenaline amount was performed. Finally, all morphological results were subjected to QAI. Our results suggest that: (1) total innervation of the thymus increases with age; (2) ANF do not change with age; (3) the content of noradrenaline in the thymus increases with age; and (4) NPY-like immunoreactive structures in the thymus decrease with age. Biochemical results are in accordance with the morphological ones and both are confirmed by means of QAI. The probable function of sympathetic innervation of rat thymus is also discussed.

Adrenergic Fibers↗
PubMed1999

Occurrence of gamma-aminobutyric acid-transaminase activity in nerve fibers of human thymus.

The specific localization of gamma-aminobutyric acid-transaminase (GABA-t) in the thymus of young and elderly men was studied. Our results show a specific vascular localization of GABA-t in the human thymus, and deal with the amount and distribution of GABA-t and its changes with age. Samples of human thymus were harvested throughout of 12 autopsies in infants (n = 3), as well as young (n = 3), adult (n = 3) and elderly (n = 3) men. Histologic staining of the human thymus was performed with eosin-orange, while histologic staining of nerve fibers was performed with the Bodian method. Histochemical and biochemical demonstration of GABA-t, including protein dosage, was performed by the methods of Van Gelder and Jung, respectively. Finally, quantitative analysis of images was performed. Staining with eosin-orange reveals the micro-anatomical details of the thymic micro-environment. The Bodian method shows the nerve fibers and neurofibrils. Histochemical staining for GABA-t shows an increase of this enzyme with age and a marked localization in the nerve fibers of the thymus in infant, young, adult, and elderly men, as well as specific vascular localization of this enzyme. These biochemical data are in accordance with the histoenzymatic results and confirm all of our previous observations. Finally, quantitative analysis of images performed on slices let us confirm all the morphological changes induced by age. We can conclude that GABA is an inhibitory neurotransmitter of the human thymus, while GABA-t plays an important role in GABA metabolism.

4-Aminobutyrate Transaminase↗
PubMed1999

Determination of dopamine D1 receptors in the human uveo scleral tissue by light microscope autoradiography.

The aim of this paper is to clarify the distribution of Dopamine D1 (DA D1) receptors in the uveo-scleral tissue of human eyes with or without elevated intraocular pressure (IOP) and to study the relationships between DA D1 receptors and uveo-scleral tissue. Samples of human uveo-scleral tissue were taken from seven men undergoing eye surgery for a traumatic lesion of the anterior segment of the eye, without involvement of the iris-corneal angle and /or from eye donors. The subjects (in whom one eye bulb had been surgically enucleated) had been previously enrolled in our medical protocols because they suffered for increased IOP, while the eye donors (of both eye bulbs) had a normal IOP. Frozen sections from the uveo-scleral tissue were submitted to biochemical characterization and to morphological autoradiographic techniques for detection of DA-D1 receptors. [3H]-SCH-23390 was used as a ligand of Dopamine D1 receptors. [3H]-SCH 23390 was bound by sections of the human uveo-scleral tissue. The pharmacological profile of the binding was consistent with the labeling of D1 receptors. Light microscope analysis was used for localization of D1 receptors and revealed an accumulation of the radioligand in the human uveo-scleral tissue. In eyes with normal IOP there is a high reaction. The Bmax of radioligand decreases in the eyes with increased IOP. The possibility that dopaminergic receptors play a role in the controlling uveo-scleral tissue functions is suggested.

Adult↗
PubMed1999

Localization of dopamine receptors in the rabbit cornea.

PURPOSE: To analyze the pharmacologic profile and the anatomic localization of the dopamine D1 and D2 receptors in sections of the rabbit cornea in normal conditions. METHODS: Samples of rabbit cornea were drawn. Biochemical and autoradiographic techniques were used on frozen sections. [3H]SCH-23390 was used as a ligand of dopamine D1 receptors and [3H]spiroperidol as a ligand of dopamine D2 receptors. RESULTS: [3H]SCH-23390 and [3H]spiroperidol were bound by sections of the rabbit cornea. The pharmacologic profile of the binding was consistent with the labeling of D1 and D2 receptors, respectively. Light microscopic analysis of the localization of D1 and D2 receptors revealed an accumulation of the two radioligands in the epithelial and in the endothelial layers of the cornea. CONCLUSION: A possible role of the dopaminergic system in the control of the corneal functions is suggested.

Animals↗
PubMed1999

Occurrence of GABA-transaminase in the thymus gland of juvenile and aged rats.

The occurrence and distribution of GABA-transaminase (GABA-t) activity were examined in the thymus of juvenile, adult and aged rats, using enzyme-histochemical and biochemical methods. Quantitative image analysis showed that specific GABA-t reactivity was localized in the wall of the arteries and, to a lesser extent, to the veins. Only a low activity could be observed in association with the subcapsular and medullary part of the parenchyma of the thymus. Many structures resembling nerve fibers also showed low positive reactivity. Biochemical results gave the following decreasing order of GABA-t activity: arteries, veins, whole thymus and parenchyma. Histoenzymatic staining and related values of quantitative analysis of images, are in agreement with the biochemical results; moreover, they demonstrated that the intensity of histoenzymatic staining for GABA-t in thymus of rats strongly decreases with age. GABA-t in thymic tissue is concentrated in blood vessels and particularly in the arteries. Therefore, our findings do not support the earlier assumptions that GABA-t is exclusively concentrated in cerebral vessels. Moreover, the decrease of GABA-t activity during age in thymic tissues may be related to the decrease of thymic microvessels as consequence of the thymic involution. On the contrary, the thymic macrovessels show an elevated staining in all ages with an apparent increase due to the thymic involution.

4-Aminobutyrate Transaminase↗
PubMed1998

Nerve fibers--mast cells correlation in the rat parietal pleura.

Our results show that a morphological correlation exists between catecholaminergic nerve fibers and mast cells in the rat parietal pleura. Mast cells are found in proximity to catecholaminergic nerve fibers. Moreover we have demonstrated that mast cells and nerve fibers in the perivascular areas of rat parietal pleura show the same formaldehyde fluorescence. In rats previously sympathectomized with neurotoxin 6-OHDA the nerve fibers appear disarranged and poorly fluorescent and related mast cells show a low fluorescence. The importance of this correlation and the possible role of mast cells are discussed.

Animals↗
PubMed1998

Venous drainage of the stomach in the golden hamster (Mesocricetus auratus) and the guinea pig (Cavia aperea f. porcellus).

Venous drainage patterns of the stomach were studied in 30 golden hamsters (Mesocricetus auratus) and in 30 guinea pigs (Cavia aperea f. porcellus). In golden hamsters the most frequent group had a v. gastroepiploica dextra (85.6% of cases). The v. gastroepiploica sinistra was found in 63.3% of cases. In the second group, the venous drainage pattern was without a v. gastroepiploica dextra (13.3% of cases). The only constant venous channel from the stomach was the v. gastrica sinistra. Other veins draining the stomach were vv. gastricae (tributaries of the v. lienalis) and interorgan venous anastomoses with neighbouring organs. A venous arch along the curvatura ventriculi major was not observed in any of the cases. In the guinea pig, the first group with a v. gastroepiploica dextra accounted for 90.0% of cases while the second group without this vein represented 10.0% of cases. The only constant venous channel was, once again, the v. gastrica sinistra. Other veins of the stomach were similar to those in the golden hamster. A venous arch along the curvatura ventriculi major was found in 76.6% of cases. Some differences in the venous pattern between the two animal species can be explained by zoological differences in these mammals. The results obtained also stimulate interest in the study of possible variations in venous patterns of the stomach in man.

Animals↗
PubMed1998

Venous drainage of the stomach in the domestic rabbit (Oryctolagus cuniculus f. domestica, breed large Chinchilla) and the domestic cat (Felis catus L. f. domestica).

Two basic patterns of venous drainage of the stomach were found in rabbits. In the first, which is highly prevalent (27 cases-90.0%), the v. gastroepiploica dextra is present while no such vein is present in the second one. Other venous channels are represented by the v. gastrica sinistra and by tributaries of the v. lienalis. In cats there are also two basic patterns of the stomach venous drainage. The first highly prevalent type without the v. gastroepiploica dextra was found in 23 cases (76.0%); in the second type this vein was present. In rabbits the v. gastroepiploica sinistra was observed in 25 cases (82.5%), in cats in only two cases (6.6%). The v. gastroepiploica dextra in the rabbit is usually a tributary of the v. portae, while in cats it is a tributary of the v. lienalis. In ten rabbits (33.3%) there was a venous arch around the curvatura ventriculi major, while in cats it was absent. The great difference in the stomach venous pattern in rabbits and cats can be explained by the different zoological position of these two kinds of animals.

Animals↗
PubMed1998

Occurrence of cholinergic nerve fibers in the human uveoscleral tissue.

We have studied the cholinergic nerve fibers (CNF) of human uveoscleral tissue in normal and pathological conditions (intraocular pressure: (IOP) of various degrees ) and have performed a quantitative image analysis of CNF with the aim of studying an hypothetical association between IOP and the uveoscleral level of cholinergic neurotransmitter in nerve fiber of the enucleated human eyes. Eleven patients, previously enrolled in our medical protocols are affected by an increase of IOP of various degrees, were subjected to surgical enucleation of one eyeball for traumatic or neoplastic reasons and were the donors of samples of the uveoscleral tissue for CNF demonstration. The samples were also submitted to quantitative image analysis. An enzymatic activity, Acetylcholinesterase (AChe), is present in nerve fibers that innervate the human uveoscleral tissue. The AChe-positive nerve fibers represent about 7.2% of the observed area in normal conditions, while in patients with elevated IOP AChe activity is about 20.3% of the total observed area. The increase of AChe activity in our experiments, all performed under the same conditions, and therefore, with comparable results, may be related with the increase of IOP.

Acetylcholinesterase↗
PubMed1998

Cerebral dura mater and cephalalgia: relationships between mast cells and catecholaminergic nerve fibers in the rat.

The aim of the present study was to examine whether mast cells have the same variations as the related catecholaminergic nerve fibers. Chemical sympathectomy or surgical removal of right superior cervical ganglion induced a rapid decrease of fluorescence in both nerve fibers and mast cells, as confirmed by quantitative analysis (nerve fibers 19 +/- 1.1 vs 1.3 +/- 0.6; mast cell 10.8 +/- 1.9 vs 2.1 +/- 0.3). The results of quantitative analysis after nerve fiber stimulation (electrical), however, showed an increase of the fluorescence in both the nerve fibers and the mast cells (nerve fibers 43.4 +/- 2.4; mast cells 18.6 +/- 1.6). Moreover, we found that the basal zone is more innervated (regarding catecholaminergic nerve fibers) than the apical one, and that the fluorescence level decreases passing from the vasal zone to the perivasal and intervasal zones. Further studies are needed in order to clarify the role of fluorescent nerve fibers and mast cells of cerebral dura mater in cephalalgia.

Animals↗
PubMed1998

Catecholaminergic innervation of the human dura mater involved in headache.

The catecholaminergic innervation of cranial dura mater in humans was studied by examining several dural zones (vascular, perivascular, intervascular) in different regions (basal, calvarial, occipital, frontal, tentorial, parietal, temporal). The results demonstrate that catecholaminergic nerve fibers are present in human cranial dura mater and that these fibers, after exposure to formaldehyde vapors, show the specific fluorescence of catecholamines. There are more dural catecholaminergic nerve fibers in the basal region than in the calvarial region. Moreover, these nerve fibers are more abundant in the perivascular dural zone than in the intervascular zone. We hypothesize that these catecholaminergic nerve fibers may be involved in headache.

Aged↗
PubMed1998

Catecholaminergic nerve fibres in normal and alkali-burned rabbit cornea.

BACKGROUND: In recent years anatomic research has demonstrated the presence of various types of nerve fibre in the cornea. The purpose of this study was to investigate the distribution of catecholaminergic fibres in various corneal layers and to study the effects of an experimental superficial corneal lesion on the pattern of catecholaminergic nerve fibre distribution in the various corneal layers. METHODS: Three weeks after the creation of an alkali burn in the centre of the right cornea of five albino rabbits, the animals were killed, and histologic sections from the cornea of both eyes were stained for observation of catecholaminergic nerve fibres and photographed on black-and-white film. The photographs were examined using the Quantimet image analyser (Leica). RESULTS: Catecholaminergic nerve fibres were observed in the corneal epithelium and the deep stromal layers. Sections from injured cornea showed a drastic reduction in epithelial and superficial stromal catecholaminergic nerve fibres, whereas the nerve fibres in the endothelium and deep stroma were not damaged. INTERPRETATION: Although catecholaminergic nerve fibres were observed in all corneal layers, the pattern of catecholaminergic fibres following the creation of a superficial lesion of the cornea seems to suggest that the superficial and deep nerve fibres may have a different distribution.

Animals↗
PubMed1997

Venous drainage of the stomach in the laboratory mouse (Mus musculus v. alba) and the laboratory rat (Rattus norvegicus v. alba).

The authors studied the venous drainage pattern of the stomach in 30 adult laboratory mice (Mus musculus v. alba) and in 31 adult laboratory rats (Rattus norvegicus v. alba) of both sexes. In mice, two basic patterns of the venous drainage of the stomach have been found, the first one (50.0% of cases) with a vena gastroepiploica dextra, while in the second pattern (50.0% of cases) the vena gastroepiploica dextra is absent and the venous blood from the curvatura major ventriculi and fundus ventriculi is drained only via the v. lienalis. In rats, three basic patterns of venous drainage of the stomach were found, the first group (35.2%) with the v. gastroepiploica dextra, the second group (38.4%) with prevalence of the v. gastrica sinistra and the third group with various tributaries of the v. lienalis from the stomach (25.6%). The vena gastrica sinistra is the only constant venous channel in both animals examined. Between interorganic venous anastomoses in the mouse and the rat no great differences exist. In spite of the great variability of veins the results indicate that it is possible to differentiate some basic patterns of the venous drainage of the stomach in the animals studied.

Animals↗
PubMed1997

Evidence of a kallikrein inhibitor in human kidney. A new ring of the kallikrein-renin-angiotensin-aldosterone chain.

By means of immunohistochemical reactions, the authors proved the inhibitor II-related immunoreactivity in distal convoluted tubules of human kidney. A sharp inhibitor II-related immunoreactivity was also present in the blood vessels' wall. On the contrary, in the wall of proximal tubules and glomeruli only low reactivity was found. The demonstration of an inhibitor II-related immunoreactivity in the distal convoluted tubules and vessels of human kidney represents a strong evidence that an inhibitor of kallikrein exists and acts also in humans as an important key in the kallikrein-renin-angiotensin-aldosterone chain and hitherto confirms the experimental data of the literature. The proved inhibitor in the human kidney may intervene in the modulation of the kallikrein-kinin system and thus represents a key role in the intrarenal mechanisms related to the blood flow and arterial pressure regulation.

Blood Pressure↗
PubMed1997

Angiomegaly.

The authors report a clinical and ultrastructural study on a group of patients with angiomegaly, a vascular disorder characterized by elongated and distended blood vessels affecting the arterial (arteriomegaly) and/or venous system (venomegaly). The arterial group, drawn from a large arteriographic series, focuses on a comparison between atherosclerotic arteriopathy and arteriomegaly. The venous group, drawn from a large ultrasound series of vein disorders, is made up of patients with venomegaly. Venomegaly gives rise to few or no symptoms and it appears to be less frequent than arteriomegaly but as the latter proved to be associated in the majority of cases studied. Based on ultrastructural findings, the chief abnormality of angiomegaly seems to lie in a specific alteration of the elastic component of the vessel wall. We found slightly osmiophil amorphous elastic material neighbouring the basement membrane of the myocytes of the vessel walls. In the superficial parts of these myocytes occurred a great number of pinocytotic vesicles indicating for a rich creation of the new elastic material. Middle or highly osmiophil thick elastic fibers with irregular side protrusions were also found among myocytes remembering the moth-eaten picture. Results from a large ultrasonographic study on patients' relatives suggest an inheritability of this vascular disorder.

Aged↗
PubMed1995

Influence of long-term treatment with the dihydropyridine-type calcium antagonist nicardipine on renal microanatomical changes in spontaneously hypertensive rats.

1. The influence of hypertension and treatment with the dihydropyridine-type Ca2+ antagonist, nicardipine, on the structure of the kidney was assessed in spontaneously hypertensive rats (SHR) of 12 weeks of age. Treatment went for 8 weeks with a daily oral dose of 1 mg/kg of nicardipine. 2. Control SHR exhibited hypertension and microanatomical vascular and glomerular changes. Vascular changes consisted of a thickening of the tunica media and decreased luminal area of medium- and small-sized intrarenal artery branches. Glomerular changes included glomerulosclerosis and atrophy of varying degrees. 3. Administration of nicardipine significantly reduced blood pressure. The drug also decreased the thickening of tunica media and luminal narrowing of renal artery branches as well as the degree of glomerular injury in SHR. 4. These data indicate that nicardipine treatment is able to control elevated blood pressure in SHR, and to counter hypertension-dependent microanatomical impairment of the kidney. This suggests that the compound exerts a protective effect on hypertensive kidney.

Animals↗