RESUMEN
In order to determine whether all the extrinsic salivary glands synthesize transferrin mRNA, the polyadenylated ribonucleic acids [poly(A)+ RNAs] from parotid, submandibular, and sublingual glands, liver, midbrain, testis, spleen, heart, kidney, and the mucosae of oesophagus and stomach from adult male baboons were analysed, using oligo(dT)-cellulose chromatography, agarose gel electrophoresis, followed by transfer of the mRNAs to nitrocellulose filters and identification with transferrin and tubulin cDNA probes. Transferrin and tubulin mRNAs were visualized by autoradiography and analysed by measuring specific activity from beta emitting nuclides following transfer to nitrocellulose filters and hybridizing with [alpha-32P]-labelled human transferrin and tubulin cDNA probes. The results indicate that transferrin mRNA is present in all the extrinsic salivary glands (submandibular, sublingual, parotid) of baboons.
Asunto(s)
ARN Mensajero/biosíntesis , Glándulas Salivales/metabolismo , Transferrina/biosíntesis , Animales , Northern Blotting , Regulación de la Expresión Génica , Masculino , Mesencéfalo/metabolismo , Membrana Mucosa/metabolismo , Especificidad de Órganos , Papio/metabolismo , Testículo/metabolismo , Transferrina/genética , Tubulina (Proteína)/biosíntesis , Tubulina (Proteína)/genética , Vísceras/metabolismoRESUMEN
The distribution of the cell adhesion proteins vitronectin, fibronectin, tenascin, and laminin as well as several integrin subunits, alpha 2, alpha 5, and alpha v, was studied in primate periodontal tissues. Full baboon mandibular sections were analyzed by immunohistochemical methods in order to localize the molecules studied in both soft and hard tissues. Vitronectin was associated with the connective tissue of the marginal gingiva, the periodontal ligament, as well as the endosteum and periosteum. A notable finding was the particularly high staining intensity of vitronectin in the periodontal ligament. Fibronectin was widely distributed in the periodontal connective tissue and was also localized to the pericellular matrix of osteocytes and blood vascular elements. Epithelial basement membranes stained positively for both fibronectin and tenascin. These proteins were also expressed in the periosteal and endosteal connective tissues and the periodontal ligament. The staining intensity for tenascin was higher in zones along the cementum and bone surfaces. Laminin was, characteristically, limited to basement membranes of epithelium and endothelium. The distribution of fibronectin, tenascin, and laminin is related to previous findings in other species. The localization of the several integrin alpha-subunits is also described in full baboon mandibular sections. The vitronectin receptor (alpha v) had a uniquely strong expression in osteoclasts of the alveolar bone and was found, at lesser intensity, on periodontal ligament fibroblasts. The fibronectin receptor alpha subunit, alpha 5, was also observed on osteoclasts, and, in addition, was widely distributed on fibroblasts, cementoblasts, and osteoblasts.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Moléculas de Adhesión Celular/análisis , Integrinas/análisis , Periodoncio/ultraestructura , Proceso Alveolar/química , Proceso Alveolar/ultraestructura , Animales , Proteínas Portadoras/análisis , Moléculas de Adhesión Celular Neuronal/análisis , Colágeno/análisis , Tejido Conectivo/química , Tejido Conectivo/ultraestructura , Cemento Dental/química , Cemento Dental/ultraestructura , Proteínas de la Matriz Extracelular/análisis , Femenino , Fibronectinas/análisis , Encía/química , Encía/ultraestructura , Glicoproteínas/análisis , Inmunohistoquímica , Laminina/análisis , Papio , Ligamento Periodontal/química , Ligamento Periodontal/ultraestructura , Periodoncio/química , Periostio/química , Periostio/ultraestructura , Receptores de Superficie Celular/análisis , Receptores de Colágeno , Receptores de Fibronectina , Receptores Inmunológicos/análisis , Receptores de Vitronectina , Tenascina , VitronectinaRESUMEN
Ten mouse monoclonal antibodies were prepared against cultured bovine periodontal ligament cells to be used as reagents for the study of periodontal disease and wound healing. Using standard immunohistochemical methods, these antibodies were found to recognize cell surface antigens in formalin-fixed bovine periodontium. Three of the 10 monoclonal antibodies (i.e., PDL-1, PDL-2, and PDL-10) cross-reacted with cells found in primate periodontium. While the isolated monoclonal antibodies appeared to distinguish subpopulations of cells located in the supporting tissues of teeth, immunohistological examination of other organs (dermis, kidney, skeletal muscle, thyroid, and parotid gland) indicated that a number of cell types of mesenchymal origin share an antigen(s) found on periodontal cells. The monoclonal antibodies described in this report should prove to be useful in studies of periodontal disease and guided tissue regeneration by providing both analytical reagents and immunochemical methods for isolating selected cell populations of the periodontium.
Asunto(s)
Anticuerpos Monoclonales/aislamiento & purificación , Ligamento Periodontal/inmunología , Animales , Anticuerpos Monoclonales/biosíntesis , Especificidad de Anticuerpos , Líquido Ascítico/inmunología , Western Blotting , Bovinos , Línea Celular , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente , Humanos , Técnicas para Inmunoenzimas , Ratones , Ratones Endogámicos BALB C , PapioRESUMEN
Nuclear uptake and retention of 3H-estradiol by luteinizing hormone (LH) and prolactin (PRL) cells was examined in three species of rodents (guinea pigs, hamsters and gerbils) using the combined techniques of immunocytochemistry and autoradiography. Castrated animals were injected with 3H-estradiol and decapitated 1.5 h later. The pituitary glands were processed for thaw-mount autoradiography followed by conventional immunocytochemical staining for LH and PRL. 3H-estradiol accumulated in more than 80% of the anterior pituitary cells in the gerbils, while only 33 and 22% of the cells accumulated 3H-estradiol in the hamsters and guinea pigs, respectively. A varying percentage of immunoreactive LH and PRL cells in all three species were found also to contain binding sites for estradiol. Some LH and PRL cells in hamsters and guinea pigs and only some in PRL cells of gerbils were found to be devoid of grains. Quantitative analysis revealed that the number of grains per nucleus differed considerably from cell to cell. LH cells of guinea pigs accumulated much larger amounts of 3H-estradiol than did the PRL cells, while the LH cells in the hamsters and gerbils accumulated only slightly more 3H-estradiol than the PRL cells. These results confirm the previous observations in rats and baboons that demonstrated tremendous species differences in percentage of cells in the anterior pituitary gland that accumulated 3H-estradiol. Also, these data suggest that there are functionally heterogeneous cell types among the LH and PRL cells in hamsters, guinea pigs and gerbils as has been previously demonstrated in rats and baboons.
Asunto(s)
Estradiol/metabolismo , Adenohipófisis/metabolismo , Receptores de Estradiol/metabolismo , Receptores de Estrógenos/metabolismo , Animales , Autorradiografía , Núcleo Celular/metabolismo , Núcleo Celular/ultraestructura , Cricetinae , Gerbillinae , Cobayas , Inmunoensayo , Hormona Luteinizante/análisis , Masculino , Mesocricetus , Orquiectomía , Adenohipófisis/citología , Prolactina/análisis , Especificidad de la Especie , TritioRESUMEN
Sex steroids have been shown to have a marked effect on the physiologic activities of the liver and the gastrointestinal tract. We performed autoradiographic studies using [3H]estradiol and [3H]dihydrotestosterone on male and female baboons for the purpose of identifying estrogen or androgen receptors, or both, in the liver, pancreas, stomach, and small and large intestines of baboons. Evidence for the presence of estrogen and androgen receptors was made apparent by high concentrations of silver grains over the nuclei of the cells of these tissues. Androgen receptors were largely confined to the nuclei of the smooth muscle cells of the tunica muscularis of the gut wall and the connective tissue interstitial cells of the liver, pancreas, stomach, and intestines. Estrogen receptors were prominent in the nuclei of the vascular smooth muscle cells in the liver, pancreas, gut, and the majority of the endocrine islet cells. These observations suggest that a variety of different cell types of the liver, pancreas, and gastrointestinal tract contain estrogen and androgen receptors that might modulate their cellular activities and influence several different physiologic processes.
Asunto(s)
Sistema Digestivo/metabolismo , Mucosa Gástrica/metabolismo , Hígado/metabolismo , Páncreas/metabolismo , Papio/metabolismo , Receptores Androgénicos/metabolismo , Receptores de Estrógenos/metabolismo , Animales , Autorradiografía , Femenino , MasculinoRESUMEN
Autoradiographic studies using the synthetic progestin [3H]ORG-2058 (16 alpha-ethyl-21-hydroxy-19-nor-[6,7-3H]pregn-4-ene-3,20-dione) were conducted on female baboons. Numerous silver grains from the exposed photographic emulsion appeared discretely localized over the nuclei of the islets of Langerhans of the pancreases of baboons injected with [3H]ORG-2058. These observations indicate that islet cells might contain receptors for progestins and, combined with clinical observations by others, suggest that progestins have a direct effect on the islet cells and may modulate the release of insulin and/or other islet hormones.
Asunto(s)
Islotes Pancreáticos/metabolismo , Receptores de Progesterona/metabolismo , Animales , Autorradiografía , Núcleo Celular/metabolismo , Femenino , Insulina/metabolismo , Secreción de Insulina , Papio , Pregnenodionas/metabolismoRESUMEN
Biopsy samples of gastric mucosa were obtained at endoscopy from patients suspected of having intestinal metaplasia. These samples were prepared for light microscopy and scanning electron microscopy. Observations of the luminal surface of the gastric mucosa in the scanning electron microscope revealed distinct topographic differences in the intestinalized and nonintestinalized regions. The latter area showed features consistent with those described in chronic gastritis, i.e., the exaggeration of the "cobblestone relief" appearance of the luminal surface of the stomach and the presence of numerous short, stubby, bulbous microvilli which project from the free border of the surface mucous cells toward the lumen of the stomach. The intestinalized region revealed a plush microvillous (striated) border periodically interrupted by apical openings of goblet cells. The scanning electron microscope is a useful research aid for examination of cell membrane expressions of the surface cells of the gastric mucosa not totally appreciated by light microscopy and transmission electron microscopy.
Asunto(s)
Mucosa Gástrica/patología , Gastritis/patología , Endoscopía , Humanos , Intestino Delgado , Metaplasia , Microscopía Electrónica de RastreoRESUMEN
Previous reports have indicated that certain sex steroids are intimately involved in the physiologic activities of the gastrointestinal tract. We performed autoradiographic studies using [3H]estradiol and [3H]dihydrotestosterone on male and female baboons for the purpose of identifying estrogen or androgen receptors, or both, in the lower and midregions of the esophagus. Discrete sites of localization of exposed photographic emulsion were observed over nuclei of skeletal muscle and interstitial cells of male baboons injected with the estrogen. No localization of receptors was observed in these same cells in females given estrogen nor in any male and females injected with the androgen. These observations suggest that skeletal muscle and interstitial cells of the male baboon contain specific high-affinity estrogen receptors that might have a direct effect on the skeletal muscle cells and may modulate their cellular activities.
Asunto(s)
Autorradiografía , Esófago/análisis , Papio , Receptores Androgénicos/análisis , Receptores de Estrógenos/análisis , Receptores de Esteroides/análisis , Animales , Femenino , MasculinoRESUMEN
Previous clinical studies have indicated that during pregnancy and following administration of contraceptives women show altered carbohydrate metabolism. We performed autoradiographic studies using 3H-estradiol-17 beta and 3H-dihydrotestosterone on male and female baboons. Discrete sites of localization of exposed photographic emulsion were observed over nuclei of cells of the islets of Langerhans of the pancreases of baboons injected with estrogen but not over those of baboons injected with androgen. These observations that islet cells contain specific receptors for estrogen when combined with the clinical observations, suggest that estrogens have a direct effect on the islet cells that may modulate the release of insulin.
Asunto(s)
Islotes Pancreáticos/análisis , Receptores de Estrógenos/análisis , Animales , Autorradiografía , Núcleo Celular/análisis , Dihidrotestosterona/metabolismo , Estradiol/metabolismo , Femenino , Islotes Pancreáticos/metabolismo , Masculino , Papio , Receptores de EstradiolRESUMEN
Little is known about the specific effects of defined formula diets (DFD) on mucosal growth of the small intestine, pancreas, or liver. In the present study male Sprague Dawley rats weighing 220 to 250 g were fed isocaloric amounts of DFD (61 kcal/day) by continuous intragastric infusion. The diets fed were Vivonex, Vivonex-HN, Flexical, and Ensure. Oral chow-fed rats with intragastric water infusions served as reference. All groups gained weight: chow 50.50 g, Vivonex 21.17 g (P < 0.005), Vivonex-HN 25.40 g (P < 0.005), Flexical 30.5 g (P < 0.01), Ensure 39.29 g (NS). After 2 weeks rats were killed, the small bowel excised, rinsed, and divided into eight equal segments. Mucosal weight, DNA, and protein concentration per centimeter segment were measured. The pancreas was also removed, homogenized, and amylase activity assayed (units/g). Livers were excised, weighed, lipid content measured, and liver histology was examined by light microscopy. Mucosal weight, DNA, and protein concentrations per segment were decreased significantly in most bowel segments of DFD fed rats. Amylase activity per gram pancreas was significantly reduced in rats fed Vivonex, Flexical, and Ensure, Serum amylase activity was also lowered in animals on DFD. There was significant accumulation of lipid in the liver of Vivonex and Flexical animals (P < 0.01). Liver histology confirmed the striking increase in fat in the Vivonex and Flexical groups. These effects may result from differences in DFD absorption, mucosal metabolism, stimulation of enteric hormone release, and/or bile and pancreatic secretions.
Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Fenómenos Fisiológicos del Sistema Digestivo , Alimentos Formulados/normas , Adaptación Fisiológica , Animales , Nutrición Enteral , Mucosa Intestinal/fisiología , Intestino Delgado/fisiología , Hígado/citología , Hígado/fisiología , Masculino , Páncreas/fisiología , RatasRESUMEN
The proliferation of gastric mucosal cells was studied in male Sprague-Dawley rats after a 50% resection involving the proximal small intestine. Two months after the operation, resected and control animals were given either a single or four successive intraperitoneal injections of 1 muCi of [3H]thymidine per g of body weight. Animals from each group were killed 1 hr after the single injection and 3, 7, 30, and 60 days after the first multiple dose injection [3H]thymidine. The number of labeled parietal, chief, and mucous cells of the gastric glands were measured. At the 3-, 30-, and 60-day periods, the percentages of labeled parietal and chief cells were significantly increased in animals with small bowel resection when compared with corresponding controls. The percentages of labeled mucous cells of the gastric glands were also increased in animals with small bowel resection at the 3- and 7-day periods. One hour after a single injection of [3H]thymidine, the percentage of labeled gastric mucosal progenitor cells in animals with small bowel resection, although increased, was not significantly different from that in controls. It is, therefore, believed that the increases in percentage labeling of gastric glandular epithelial cells at 3, 7, 30, and 60 days could not solely be explained on the basis of an increased turnover rate of gastric progenitor cells. Rather, it might be concluded that the increase in glandular epithelial cells is accomplished, in part, by increased differentiation of gastric progenitor cells.
Asunto(s)
Mucosa Gástrica/metabolismo , Intestino Delgado/cirugía , Animales , Autorradiografía , Recuento de Células , Mucosa Gástrica/patología , Masculino , Ratas , Timidina/metabolismoRESUMEN
Pure rat bile, mixed with an equal volume of 43% ethanol or distilled water, was intubated into the stomachs of fasted rats. Control rats were intubated with saline solutions or received no intraluminal solutions into the stomachs. Following a 10 min period of exposure of the bile or saline solutions to the luminal surface of the gastric mucosa, samples of the stomachs were processed for routine scanning and transmission electron microscopy and light microscopy. Observations indicated that the bile solutions produced extensive damage to the luminal surface of the stomach. The most prominent alteration was evident as a massive cytolysis of the epithelial cells which line the gastric glands, pits, and luminal surface of the gastric mucosa. Loss of the epithelium revealed the underlying honey-combed structure of the lamina propria. In addition, haemorrhagic areas were often observed throughout the mucosa. The findings of this study indicated that bile mixed with water or ethanol was highly destructive to the gastric epithelium, even more destructive than a solution of ethanol and water; however, the basal lamina and connective tissue fibres of the lamina propria were apparently unaltered by the bile solutions. Furthermore, the presence of an intact lamina propria in many areas where there was not extensive haemorrhage, following exposure of these solutions to the gastric mucosa, suggested the existence of a scaffolding structure for the proper orientation of the reconstruction process of epithelium of the glands, pits, and luminal surface of the altered gastric mucosa.
Asunto(s)
Ácidos y Sales Biliares/farmacología , Mucosa Gástrica/efectos de los fármacos , Animales , Epitelio/efectos de los fármacos , Epitelio/ultraestructura , Femenino , Mucosa Gástrica/ultraestructura , Concentración de Iones de Hidrógeno , Masculino , Microscopía Electrónica de Rastreo , RatasRESUMEN
Male Sprague-Dawley rats (120 to 130 gm), unoperated, sham-operated, and those with a 50% resection of the proximal small intestine, were studied after periods of 3, 6, 9, or 12 months. Differences in body weight and in the surface area, thickness, volume, and cellular content of the gastric mucosa between these three groups of animals were compared and statistically analyzed. After an initial loss in body weight, animals with small bowel resection and sham-operated animals attained weights equivalent to unoperated controls. Comparison of the groups for mucosal surface areas of the body of the stomachs showed no significant differences at the 3-, 6-, or 9-month periods. However, 12 months after surgery, the mucosal surface area of stomachs from resected animals was significantly greater than in corresponding controls. At 3, 6, and 9 months after resection, the thickness and volume of the gastric mucosa and the epithelial cell populations (parietal and nonparietal) of the gastric glands were significantly greater than in controls. However, at 12 months, there was no significant difference in any of these parameters between the controls and the experimental animals. The DNA content of the gastric mucosa was significantly greater for animals with small bowel resection than for corresponding controls at 1 and 6 months after surgery. It is concluded that hyperplasia of the gastric glands exists for at least 9 months after proximal small bowel resection in the rat. This hyperplastic response may be responsible for the previously observed (N Engl J Med 272:509-514, 1965; Surgery 65:292-297, 1969) gastric hypersecretion associated with extensive small bowel resection.
Asunto(s)
Mucosa Gástrica/patología , Intestino Delgado/cirugía , Animales , Peso Corporal , ADN/metabolismo , Mucosa Gástrica/metabolismo , Hiperplasia , Intestino Delgado/patología , Masculino , RatasRESUMEN
Parietal cells of the stomach of the hamster show extensive amounts of dense material in a variety of organelles after prolonged exposure to a solution of osmium tetroxide. Conspicuous amounts of reduced osmium compounds are evident within the granular endoplasmic reticulum, perinuclear cisterna, and vesicular elements of the Golgi complex. Dense material is also apparent within cristae of the mitochondria, the surface coat of the microvilli of the intracellular canaliculus, and vesicular elements of the multivesicular bodies. Multivesicular bodies, containing numerous small osmiophilic elements, are often seen surrounding and/or in close contact with mitochondria. The proximity of the multivesicular bodies to the mitochondria appears to be related to an autophagic process involving degradation of mitochondria. The distribution and intensity of the precipitates within the organelles of the parietal cells vary in different regions of the gastric glands. The findings of this study emphasize that cell structures other than the Golgi complex may contain large concentrations of reduced osmium compounds after prolonged exposure to a solution of osmium tetroxide.