Search PubMed⌕ Search

Biomedical subjects

C Cavallotti

Publications and source records attributed to C Cavallotti.

At least 73 records · Page 4Linked to original sources
PubMed1989

Effect of acetyl-L-carnitine treatment on the density of muscarinic receptors in the brain of methylazoxymethanol-microencephalic rats.

The effect of methylazoxymethanol (MAM), administered on the 15th gestational day, on the density and pattern of muscarinic cholinergic receptors in some brain areas was assessed using combined radioreceptor binding and autoradiographic techniques. The effect of 15 days' treatment with acetyl-L-carnitine on the same parameter was also assessed. The density of muscarinic cholinergic receptors was found to be increased in the brain of MAM-microencephalic rats. Acetyl-L-carnitine administration caused a significant reduction in the density of receptors under study. A possible role of acetyl-L-carnitine in restoring central cholinergic neurotransmission is discussed.

Acetylcarnitine↗
PubMed1989

Effect of acetyl-L-carnitine treatment on brain ribonucleic acid levels in methylazoxymethanol-microencephalic rats.

The effects of methylazoxymethanol acetate (MAM) administered on the 15th gestational day, and of acetyl-L-carnitine treatment, on rat brain total and ribosomal RNA levels, were studied. In the brain of MAM-treated rats both total and ribosomal RNA concentrations were significantly reduced. Acetyl-L-carnitine treatment restored total and ribosomal RNA levels. The frontal cortex and the hippocampus were the brain areas most sensitive to acetyl-L-carnitine administration. Histochemical demonstration of tissue stores of nucleic acids showed that the loss of RNA induced by MAM occurs primarily within the cytoplasm of nerve cells in various telencephalic areas. Neuronal cytoplasmatic RNA is also sensitive to acetyl-L-carnitine treatment.

Acetylcarnitine↗
PubMed1988

Increase in substance P levels in the lung of old rats.

Substance P levels in the lung of young (3-month-old), adult (12-month-old), senescent (20-month-old) and aged (28-month-old) male Wistar rats were determined by radioimmunoassay. Levels of substance P were constant until 28 months of age when these become significantly higher (approximately more than 2 times, p less than 0.001) than the values found in younger rats. Whether the increase of substance P content in the lung of old rats may reflect changes in the density of substance P containing nerve fibres or in the content of the peptide in single nerve fibres is discussed.

Aging↗
PubMed1988

Autoradiographic localization of the GABAA receptor agonist [3H]-muscimol within rat kidney.

By the use of combined radioreceptor binding and autoradiographic techniques, the pharmacological characteristics of (3H)-muscimol binding and the localization of the label were studied. (3H)-Muscimol was bound by sections of rat kidney in a manner consistent with the existence of specific gamma-aminobutyric acid 'A' (GABAA) receptors with KD and Bmax values of 23.7 nmol/l and 1.15 pmol/mg tissue, respectively. (3H)-Muscimol was bound by convoluted tubules of the renal cortex and by the collecting tubules. Our findings demonstrating the existence of recognition sites for the GABAA receptor agonist muscimol in the kidney suggest that GABA has a role in renal function.

Animals↗
PubMed1988

The peptidergic innervation of the guinea pig uterine artery in pregnancy.

The influence of pregnancy on the density and pattern of the peptidergic innervation of the guinea pig uterine artery was studied. Whole mount stretch preparations of the uterine artery from estrus and late pregnant guinea pigs were processed for the immunohistochemical demonstration of neuropeptide Y (NPY)-, vasoactive intestinal polypeptide (VIP)-, calcitonin gene-related peptide (CGRP)- and substance P (SP)- immunoreactive nerve fibres. In late pregnancy the density of NPY- and CGRP- containing nerve fibres was remarkably decreased, while that of VIP- and SP- immunoreactive nerves showed a moderate reduction. The meaning and the possible physiological relevance of the decreased density of peptide-immunoreactive nerves in the uterine artery in late pregnancy are discussed.

Animals↗
PubMed1987

Dopamine receptors mediating the stimulation and the inhibition of adenylate cyclase in rat prostate gland.

The effect of dopamine on the 3',5'-cyclic adenosine monophosphate (cAMP) generating system of membrane particles of rat prostate gland was studied. Dopamine increased the concentration of cAMP in a dose-dependent manner. The selective D1 receptor inhibitor SCH 23390 caused a decrease in dopamine-elicited cAMP levels. Any effect of dopamine on prostatic cAMP concentration was abolished by the simultaneous addition to the incubation medium of SCH 23390 and of the D2 receptor blocking agent (-)-sulpiride. Also the D2 receptor agonist bromocriptine decreased cAMP levels. The present data indicate the existence, in the rat prostate gland, of two types of dopamine receptors mediating, respectively, the activation (D1 effect) and the inhibition (D2 effect) of adenylate cyclase activity.

Adenylyl Cyclases↗
PubMed1987

Vasoactive intestinal polypeptide levels and distribution in the penis of old rats.

Vasoactive intestinal polypeptide (VIP) levels and distribution were studied in the penis of young-adult (3-month-old) and old (30-month-old) Wistar rats by radioimmunoassay and immunofluorescence. No significant changes in tissue VIP concentrations or distribution occurred in the penis of old rats compared to young-adult rats. The present data indicate that the age-related impairment of male sexual function is not dependent on modifications of the VIP-ergic innervation of penile tissue.

Aging↗
PubMed1987

The noradrenergic innervation of the vasa nervorum in old rats: a fluorescence histochemical study.

The effect of ageing on the density and pattern of noradrenergic nerves in the perivascular nerve plexus supplying the vasa nervorum of the rat sciatic nerve was studied using combined catecholamine histofluorescence and quantitative image analysis techniques. The density of noradrenergic fibres around arteries and arterioles of the rat sciatic nerve vasa nervorum increased in the old animals. In contrast, no changes in perivascular nerve fibres supplying the veins and venules were found in the vasa nervorum of old rats. The increase in old age of noradrenergic innervation of arteries and arterioles of the vasa nervorum may be related to the pathogenesis of some peripheral nerve diseases.

Age Factors↗
PubMed1987

Quantitative image analysis of the density and pattern of adrenergic innervation of blood vessels of rat spinal cord.

The density and pattern of the noradrenergic innervation of the main extramedullary blood vessels of the rat spinal cord was studied using combined glyoxylic acid histofluorescence and quantitative image analysis techniques. The anterior spinal artery has a perivascular plexus of fine noradrenergic nerves rich in varicosities; the central artery has nerve fibers of various sizes; and the posterior spinal vein has a limited plexus of noradrenergic nerve fibers. The possible significance of the noradrenergic innervation of extramedullary spinal cord blood vessels is discussed.

Animals↗
PubMed1986

Segmental distribution and gestational changes of GABA-transaminase activity in the rat oviduct.

The occurrence and the localization of 4-aminobutyrate:2-oxoglutarate transaminase (GABA-transaminase) in the non-pregnant and pregnant rat oviduct were examined using biochemical and enzyme histochemical techniques. Specific GABA-transaminase activity was detected in the ampullary and isthmic portions of the oviduct as well as in the utero-tubal junction. The enzymic activity was lower in the ampullary than in the isthmic or intramural segments of the oviduct. Pregnancy induced a significant increase of GABA-transaminase activity in each portion of the oviduct. Enzyme histochemistry showed the highest GABA-transaminase reactivity at the level of the epithelial cells of the oviduct irrespective of the portion of the tube examined. A faint specific activity was demonstrated in the smooth muscle of the oviduct while the serosa did not show specific staining. Our findings indicate that: the observed increase of GABA-transaminase activity in the oviduct of the pregnant rat may be responsible for the reduced GABA levels in the oviduct during gestation; and the extraneuronal localization of GABA-transaminase activity does not seem to support the suggestion of a possible GABAergic innervation of the oviduct.

4-Aminobutyrate Transaminase↗
PubMed1986

Effect of acetyl-L-carnitine treatment on some behavioural, histochemical and histological parameters of methylazoxymethanol microencephalic rats.

The effect of methylazoxymethanol (MAM) administration at the 15th gestational day on some behavioural and morpho-functional parameters of rat brain was investigated. The effect of a 13-15-day treatment of acetyl-L-carnitine on the same parameters was also assessed. MAM microencephalic rats showed a significant impairment in water-maze and pole-climbing tests. The histochemical reactivity of the enzyme NADH2-tetrazolium reductase (NADHR) at the level of frontal and occipital cortex, neostriatum and hippocampus was remarkably reduced. Also cholinacetyltransferase (ChAT) immunoreactivity within nerve cell bodies of the pontine tegmentum was decreased in MAM-treated animals. On the contrary, acetylcholinesterase (AChE) reactivity was increased in all the investigated brain areas with the sole exception of the neostriatum. Nissl reactivity was decreased in the cytoplasm of the pyramidal neurons of the frontal cortex and hippocampus, and slightly increased in the cytoplasm of pyramidal neurons of the occipital cortex of MAM microencephalic rats. Acetyl-L-carnitine treatment improved the behaviour of microencephalic rats in water-maze and pole-climbing tests. Moreover the substance stimulated NADHR reactivity in the cerebral cortex and hippocampus as well as ChAT immunoreactivity in the cytoplasm of neurons of the raphe pontine nuclei. Pharmacological treatment reduced AChE reactivity in the cerebral cortex and the hippocampus, and improved the pattern of Nissl reactivity within all brain areas examined.

Acetylcarnitine↗
PubMed1985

The adrenergic innervation of rat uterine tubes in old age: a fluorescence histochemical study.

The effect of ageing on the density and pattern of adrenergic innervation of rat uterine tubes was studied using combined glyoxylic acid induced fluorescence and quantitative image analysis techniques. With age a reduction in the number of nerve fibers of the circular muscle layer of the isthmic portion was observed. No significant differences in the density of innervation were found at the level of blood vessels associated with uterine tubes.

Adrenergic Fibers↗
PubMed1985

Stimulatory effect of neonatal beta-estradiol treatment on aspartate-aminotransferase activity within rat cerebellar cortex.

The effect of neonatal beta-estradiol treatment on the Aspartate-aminotransferase (Asp-T) activity within rat cerebellar cortex has been studied using a semi-quantitative histochemical technique. The Asp-T, localized chiefly at the level of nerve fiber-like structures in the molecular layer as well as around the perikaryon of Purkinje neurons, is significantly stimulated after estrogenization. The nerve fibers localized in the molecular layer were the Asp-T cerebellar structures more remarkably influenced by beta-estradiol treatment.

Animals↗
PubMed1985

Histoautoradiographic localization of (-)-3H-dihydroalprenolol in rabbit aorta.

The distribution pattern of (-)-3H-dihydroalprenolol (3H-DHA) binding sites within the thoracic and abdominal aorta was studied using a histoautoradiographic technique. Frozen sections of rabbit aorta were incubated with 3H-DHA in the presence or absence of 1 mumol/l (-)-propranolol and of increasing concentrations of various adrenergic agents. After washing, the same secretions were placed in scintillation vials and counted to evaluate the pharmacological characteristics of 3H-DHA binding or processed for histoautoradiography. 3H-DHA was bound by sections of the rabbit aorta in a manner consistent with the presence of beta-adrenoceptors. The binding was reversible, saturable and of high affinity, with a dissociation constant Kd of 1.0 nmol/l and a maximum binding capacity Bmax of 17 fmol/mg tissue (wet weight). It was inhibited only by beta-adrenoceptor blocking drugs. Histoautoradiographic studies revealed that beta-adrenoceptors are located primarily in the media and then in the intima. The lowest density of 3H-DHA was found in the adventitia. The distribution pattern of beta-adrenoceptors in the media suggests the possible existence of two groups of beta-adrenoceptors within this layer of the aorta. The first group was found in the outer portions of the media and may be controlled by the adrenergic nerves that supply the artery. The second group was found in the portions of the media closest to the intima and is likely under the control of catecholamines coming from the lumen of the aorta.

Alprenolol↗
PubMed1984

Age-associated decrease of dopamine-sensitive adenylate cyclase in rabbit renal artery.

Using renal arteries from young (6 months), mature (18 months) and old (70 months) rabbits, the effect of dopamine on 3',5'-cyclic adenosine monophosphate (cAMP) generation was studied. No significant differences in basal adenylate cyclase values were found in homogenates of renal artery from young, mature or old rabbits. The protein content of the renal artery was also unchanged during the lifespan. Dopamine stimulated the production of cAMP. The stimulatory effect of dopamine was similar in the renal artery of young and mature rabbits but was lower by about 40% in old rabbits. The present results led us to hypothesize an impairment of the peripheral dopaminergic system in old age similar to that described for the central dopaminergic system.

Adenylyl Cyclases↗
PubMed1984

Dopamine-sensitive cAMP generating system in rat extracerebral arteries.

The effect of dopamine (DA) on the 3',5'-cyclic adenosine monophosphate (cAMP) generating system in rat extracerebral arteries was studied in order to identify DA receptors. The carotis interna and the basilar artery as well as the arteries of the circle of Willis were homogenized and centrifuged. This extracellular arterial preparation was used for studying the effect of DA, norepinephrine and of drugs interfering with alpha- and beta-adrenergic as well as with dopaminergic receptors on cAMP production. DA increased the concentration of cAMP. The DA-elicited increase of cAMP levels was inhibited by dopamine receptor blocking agents (phenothiazine derivatives and butyrophenones) but unaffected by alpha- or beta-adrenoceptor blocking drugs or by the ergot-like DA agonist bromocriptine, or by sulpiride. The findings appear to be indicative of the existence of only D1 receptors within the blood vessels studied.

Animals↗