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Biomedical subjects

G Paino

Publications and source records attributed to G Paino.

At least 19 recordsLinked to original sources
PubMed2002

Pituitary adenylate cyclase activating peptide (PACAP) immunoreactivity and mRNA expression in the duck gastrointestinal tract.

The presence and distribution of pituitary adenylate cyclase activating peptide (PACAP) immunoreactivity were studied in the duck gastrointestinal tract using immunohistochemistry and radioimmunoassays. Expression and distribution of PACAP mRNA were also studied using reverse transcriptase polymerase chain reaction (RT-PCR) and hybridization techniques. In addition, a partial coding sequence (cds) of the duck growth hormone-releasing hormone (GRF)/PACAP gene was identified. The presence of both PACAP-38 and PACAP-27 was demonstrated, the former being the predominant form. PACAP immunoreactivity was found in neurons and fibers of the enteric nervous system (ENS), in endocrine cells and in the gut associated lymphoid tissue (GALT). Double immunostaining showed that PACAP is almost completely colocalized with vasoactive intestinal peptide (VIP) in the ENS. Moreover, PACAP was also found in nitric oxide synthase (NOS)-containing neurons and nerve fibers. Radioimmunoassay (RIA) performed on denervated gut showed that more than one-half of the duodenal PACAP is extrinsic in origin. RT-PCR, Northern blot analysis and in situ hybridization confirmed the immunohistochemical data. The findings of the present study suggest that, in birds, PACAP may have multiple roles in regulating gastrointestinal functions.

Animals↗
PubMed2001

Pituitary adenylate cyclase activating peptide (PACAP) immunoreactivity in the ureter of the duck.

The presence, distribution and colocalisation of pituitary adenylate cyclase activating peptide (PACAP) immunoreactivity have been studied in the duck ureter by using Western blot analysis, radioimmunoassays (RIA) and immunohistochemistry. The presence of both PACAP-38 and PACAP-27 was demonstrated, PACAP-38 being the predominant form. PACAP-immunoreactive fibres and neurons were found in all the ureteral layers. Double immunostaining showed that PACAP was almost completely colocalised with vasoactive intestinal peptide (VIP). Moreover, PACAP was found in substance P (SP)-containing ureteral nerve fibres and in SP-containing dorsal root ganglion neurons. RIA performed on denervated ureters demonstrated that almost half of the ureteral PACAP was extrinsic in origin. These findings suggest that, in birds, PACAP has a role in diverse nerve-mediated ureteral functions.

Animals↗
PubMed2001

The weaver mutant mouse: a model to study the ontogeny of dopamine transmission systems and their role in drug addiction.

Dopaminergic neurons and their projection-systems are important in some fundamental human activities like locomotion, feeding and sex, essential for survival and procreation, and are relevant to pathologies like Parkinson's disease and drug abuse. Three main dopaminergic projection-systems, namely the nigrostriatal, mesocortical and mesolimbic pathways are the major targets of the neuropharmacological actions of psychomotor stimulants such as cocaine and amphetamine. Studies on knockout mice for dopamine or its receptors provide substantial information but fail to reveal the role of individual dopaminergic projection-systems. Mutant animals with defects specific to one or more projection-systems might be useful for studying the role of individual dopaminergic projection-systems. We propose the weaver mutant mouse, with a defective nigrostriatal dopaminergic projection-system and dopamine depletion in the dorsal striatum but with intact mesocorticolimbic projection-systems, as a suitable model to study the role of individual dopaminergic systems in diverse biological processes including Parkinson's disease and drug abuse.

Animals↗
PubMed2000

Maternal morphine alters parvalbumin immunoreactivity patterns in neonatal mouse brain.

The influence of chronic maternal morphine on the parvalbumin immunoreactive patterns in developing mouse brain was studied. Female Swiss mice were administered daily saline or morphine (30 or 60 mg/kg) for a period of 7 days before mating, gestation, and 21 days postpartum. Their pups were sacrificed on postnatal day 18 and the brains were examined histologically and immunohistochemically for parvalbumin-positive neurons. Histological observations revealed no significant changes in the cell number of the morphine-exposed neonatal forebrain, whereas the number of parvalbumin-positive neurons increased in layers II-IV of the parietal cortex I. Moreover, the number of parvalbumin-positive dendrites increased remarkably in the cingulate and parietal I cortices of the morphine-exposed neonates, indicating the region-specific increase in the PV immunoreactive profiles. These results are consistent with the key roles played by the above brain regions in the altered behavioral patterns of the maternally addicted neonates, such as impaired somatosensory and cognitive performances. The mechanism of morphine action on parvalbumin expression in neonatal mouse brain is not evident, but alterations in the expression patterns of parvalbumin in specific regions of the developing brain might be one of the cellular mechanisms by which addictive drugs modify the functional aspects of the developing CNS.

Aging↗
PubMed2000

The distribution and colocalisation of nicotinamide adenine dinucleotide phosphate reduced-diaphorase (NADPH-d)-/nitric oxide synthase (NOS)-containing neurons in the innervation of the duck ureter.

ensp;The distribution and colocalisation of nicotinamide adenine dinucleotide phosphate reduced-diaphorase (NADPH-d)-/nitric oxide synthase (NOS)-containing (nitrergic) neurons in the innervation of the duck ureter have been studied using histochemistry and immunohistochemistry. Quantitative analysis showed that nitrergic neurons made up 60% and 70% of the total intramural and adventitial neuronal populations, respectively. About 40% of intramural nitrergic neurons expressed VIP-immunoreactivity, and about 75% of nitrergic adventitial neurons expressed TH-immunoreactivity. The density of nitrergic adventitial neurons was significantly greater in the lower tract than in the upper and intermediate tracts. Nerve lesioning experiments showed that the majority of ureteral nitrergic innervation was extrinsic in origin; nitrergic adventitial neurons primarily projected caudocranially, whereas NOS-immunoreactive and NOS-/VIP-immunoreactive intramural neurons primarily projected craniocaudally. These findings suggest that, in birds, the nitrergic innervation plays a role in ureteral functions such as epithelial mucosecretion, muscular motility, and the closing and/or opening of the ureteral papilla.

Animals↗
PubMed1999

The innervation of the ureter in the duck (Anas platyrhynchos). A morphological and quantitative study.

The morphology and distribution of the innervation in the duck ureter were studied using AChE histochemistry and PGP 9.5 immunohistochemistry. The density of AChE positive ganglia and neurons was calculated in the adventitial and muscular layers both in young and adult birds. Moreover, in order to investigate regional differences in neuronal density, separate neuron counts and neuron density calculations were performed for the upper, intermediate and lower parts of the ureter, and the data were statistically evaluated. Three nerve plexuses located in the tunica adventitia, in the tunica muscularis and in the lamina propria respectively, were observed. Both in young and adult ducks, the density of adventitial neurons was significantly greater in the lower tract than in the upper and intermediate tracts. The findings of the present study suggest that, in birds, the innervation may play a role in ureteric functions such as epithelial mucosecretion, muscular motility, and closure and/or opening of the ureteric papilla.

Acetylcholinesterase↗
PubMed1999

Postnatal development of intestinal endocrine cell populations in the water buffalo.

The frequency and distribution of 11 endocrine cell populations were studied in the intestine of differently aged buffalo, grouped on the basis of diet: 2-d-olds (suckling), 5-mo-olds (weaning) and 5-y-olds (ruminant adult diet). The endocrine cell populations were identified immunocytochemically using antisera against 5-hydroxytryptamine (5-HT), somatostatin, gastrin, cholecystokinin (CCK), COOH-terminal octapeptide of gastrin/CCK, neurotensin, motilin, gastric inhibitory polypeptide (GIP), secretin, glucagon/glicentin (GLU/GLI) and polypeptide YY (PYY). In adult buffalos the regional distribution of endocrine cells is similar to that of other adult ruminants. During postnatal development, these cell types showed the following changes in their frequency and distribution: (1) 5-HT, neurotensin and gastrin/CCK immunoreactive cells (i.c.) showed a decrease in frequency with age; (2) somatostatin i.c. frequency remained stable with age; (3) motilin, GIP, secretin and CCK i.c. showed a slight increase in frequency with age; (4) GLU/GLI and PYY i.c. decreased in frequency with age in the small intestine, caecum and proximal colon and an increase in frequency in the rectum. It was hypothesised that the endocrine cell types, whose presence and localisation is substantially stable in all examined ages, probably contain substances that are strictly necessary for intestinal function. In contrast the hormones contained in the cell populations that decreased with age, are probably involved in physiological needs during the milk and weaning diet or play a role in intestinal growth.

Aging↗
PubMed1998

Chronic morphine alters calbindin D-28k immunostaining patterns in mouse forebrain.

The influence of chronic morphine treatment on the brain of adult mouse has been studied. Female Swiss mice were daily administered saline or morphine (30 or 60 mg/kg body weight) for a period comprising 7 days before mating, during gestation and until 21 days post-partum. Their brains were then perfusion-fixed and examined for histology and calbindin D-28k protein-immunoreactivity. Histological observations revealed no significant changes in the various brain regions; whereas a reduced number of calbindin-positive cells was encountered in the cingulate and parietal cortices and the lateral septal regions of morphine-treated brains compared with those of controls. The alteration in the expression-patterns of this neuroprotective calcium-binding protein in specific regions of the adult brain might be one of the mechanisms by which the addictive drugs modify the functional aspects of the CNS.

Animals↗
PubMed1994

[The microvascularization of the choroid plexus of the lateral ventricles in the goat (Capra hircus)].

The goat choroid plexus angioarchitecture of the lateral ventricles was studied under the SEM using the method of "microvascular corrosion casts". The whole plexus is semilunar shaped and directed in an antero-posterior, latero-median fashion. In the plexus the lateral extremity is larger than the median one. All the components of the vascular bed (arteries, veins and capillaries) of the choroid plexus have interesting morpho-structural features. In particular, the capillaries are more developed than the other components and they are variously located on both sides of the plexus. The capillary network has a various organization in different zones of each side of the plexus.

Animals↗
PubMed1991

Recent progress in vertebrate limb morphogenesis.

Morphogenesis of vertebrate limb, specifically that of the chick wing, has been recognized as a suitable model to study the cellular and molecular mechanisms of pattern formation. The importance of cellular inductive phenomena and the relevance of the processes such as cell division and cell death in the above model are discussed. These studies have revealed the retinoic acid (RA) and retinols as convincing candidates for vertebrate morphogens. The recent discovery that the RA receptors belong to the steroid hormone receptor superfamily might indicate the universality of the RA morphogen and might enlighten the possible mode of its action. Identification and characterization of the 1d locus genes associated with the mouse limb morphogenesis and the possible involvement of the homeobox proteins in chick wing development have opened new prospects in understanding the molecular mechanisms of vertebrate morphogenesis.

Animals↗
PubMed1991

[SEM study on the mucosa of the pre-stomach in Bubalus buffalus].

Morpho-structural features of pre-stomach mucosa in the first period of post-natal life in Bubalus buffalus have been studied by SEM. The rumen presents a well defined morpho-structural architecture from 10 to 100 days of life, while in reticulum and in omasum numerous morphological variations have been noticed. During the development, in fact, in these organs the establishment of a typical morphological pattern has been observed.

Animals↗
PubMed1990

Transplantation of Lewis lung carcinoma in mouse uterus.

Earlier studies have shown that pregnant and nonpregnant mammalian uteri respond differently to tumor cell invasion, colonization and metastasis, but the biological basis of such differential uterine response has not been clarified. In the present study we have investigated the role of the metastatic potential of the tumor in the differential response of different stages of mouse uteri, using a highly metastatic tumor. The results obtained were compared with earlier data obtained using low metastatic or nonmetastatic tumors. Lewis lung carcinoma (LLC) cells were infused nonsurgically into nonpregnant uteri of various estrus stages and into pregnant uteri on day 3 postcoitum. Response of the uteri and embryos was studied histologically on days 2, 5 and 18 posttreatment (p.t.). The embryonic development was severely inhibited resulting in extensive resorption. In the tumor cell-treated animals, despite an early and uniform invasion the patterns of tumor cell colonization and metastasis differed remarkably from the pregnant to nonpregnant uteri. On day 5 p.t. 66% of nonpregnant animals showed tumor cells in the endometrium and 40% had tumor metastasis in other organs. Though 40% of the pregnant animals had tumor cells in the uteri, none had metastasis in other organs. By day 18 p.t., despite the absence of tumor cells in the uteri, 75% of nonpregnant animals showed metastasis in lung and liver. In pregnant animals, tumor cells were seen neither in uteri nor in other organs studied. These results indicate the refractory nature of both the pregnant and nonpregnant mouse uteri to the survival and colonization of LLC cells, but the mechanisms by which the tumor cells are eliminated differ between these two types of uteri.

Animals↗
PubMed1989

The vascularization of the Bursa cloacalis (of Fabricius) in the duck.

The morphological and structural features of the vascular component of the bursa of Fabricius in the duck are described. By means of an intravasal perfusion of suitably colored neoprene Latex or Microscopaque, or a perfusion of Indian ink, it was possible to follow visually the routes of arteries, veins and the microcirculation; this last represents a major characteristic of the bursal follicle in the duck. The microcirculation has its origins in several roots arising from the follicular arterioles, which in the region of the cortex constitute an open vascular layer. From these pre-capillary arterioles, adjacent to the limiting layer between cortex and medulla, a dense capillary network is formed. With the aid of an electron microscope the presence of a cortico-medullary barrier of an epithelio-reticular nature was revealed; close to it there are the terminal branches of the intrafollicular network. The barrier appears to be structurally more compact than that of the cortical capillaries of the mammalian thymus.

Animals↗
PubMed1989

Chromogranin- and somatostatin-containing neuroendocrine cells in the porcine uterus. An immunocytochemical study.

Endocrine cells scattered in organic mucosae were defined "Neuroendocrine" (NE) cells because they constitute a section of the Diffuse Neuroendocrine System (DNES). Such cells have never been evidentiated in the normal endometrium. By means of histochemical and immunohistochemical techniques, NE cells, some of which contain the hormone somatostatin, are described in the glandular epithelium of the uterine horn in non-pregnant, non-castrated, young and adult sows. As is known, the uterine horn is the organ of pregnancy in the pig. The localization, distribution and morphology of the uterine NE and somatostatin-containing cells are reported and the importance of their function, in the pregnant and non-pregnant porcine uterus, is discussed.

Animals↗
PubMed1989

Invasion and metastasis of Lewis lung carcinoma in the mouse uterus.

Patterns of Lewis lung carcinoma (LLC) cell invasion, colonization and metastasis were studied in C57 mouse uteri. LLC cells (5 X 10(4) in 0.05 ml) were infused nonsurgically into nonpregnant and pregnant uteri, 3 days postcoitum. The fate of cells was studied histologically on days 2, 5 and 18 posttreatment (PT). Despite a large degeneration of LLC cells in the lumina of both the pregnant and nonpregnant mice, in 38% of these uteri, tumor cells had invaded the endometrium by day 2 PT. However, subsequent distribution of tumor cells differed remarkably between the pregnant and the nonpregnant uteri. By day 5 PT, in 66% of the nonpregnant mice, tumor cells were common in the endometrium and metastases in other organs were seen in 40% of the animals. But in the pregnant mice only 40% uteri showed tumor cells and no metastasis was recorded. On day 18 PT tumor cells were rare in the nonpregnant uteri, but significantly, 75% of those animals showed lung and liver metastases. In pregnant mice, tumor cells neither survived in the uteri nor metastasized to other organs. LLC cells, infused into nonpregnant uteri, promptly metastasized to lungs without colonizing the uteri: this unique system may provide insight into the effects of organ-specific host factors on the growth and metastatic potential of tumor cells.

Animals↗
PubMed1989

[Morphostructural features of the pleural lymphatic circulation in the pig].

The morphostructural features of the lymphatic circle of swine visceral pleura were investigated by means of vital dye injection in the pleural cavity. In the animals treated as mentioned previously it was possible to observe that in the visceral pleura the superficial lymphatic network had formed the very thick mesh, while the underlying pulmonary parenchyma was not interested. This behaviour lets us suppose that the drainage of the visceral pleura is mainly a direct one.

Animals↗
PubMed1988

Influence of mouse uterus on the metastatic patterns of tumour cells.

Metastatic patterns of fibrosarcoma (FS) and Lewis lung carcinoma (LLC) cells transplanted into mouse uteri of various reproductive stages, were investigated. Tumour cells were infused non-surgically into the lumen of 3-day post coitum pregnant uterus or into non-pregnant uterus of known estrus stage. The fate of these tumour cells was studied histologically on days 2, 5 and 10 post treatment. No significant difference in the metastatic patterns of the FS or the LLC cells was seen between the non-pregnant uteri of various estrus stages. FS cells in few cases of non-pregnant uteri displayed the tendency to migrate and grow outside the myometrium without colonizing in the endometrium, but in pregnant uteri they colonized within the endometrium. LLC cells in the non-pregnant uteri promptly metastasized to distant organs like liver and lung; but those in the pregnant uteri rarely metastasized to other organs. These observations imply that the metastatic patterns of uterine tumour might depend on both the physiological state of the uterus and the tumour cell type.

Animals↗