Hypertrophy Of Epithelial Cells Research Articles

1] Methods of bursectomy

This chapter explores that bursectomy helps to reduce or eliminate humoral immunity. It reviews historical and recent experiments with the bursa. It also critiques the various methods of bursectomy such as surgical bursectom and hormonal bursectomy. The chapter discusses that surgical bursectomy performed at hatch is more effective than the bursectomy performed at later ages. However, numerous investigators have reported that chicks bursectomized at hatch respond to a secondary and tertiary injection of antigen. The chapter also discusses that hormonal bursectomy may be effected by dipping eggs in steroid solutions. The dipping technique will either eliminate the bursa in the hatched chick or markedly reduce its size with general hypertrophy of epithelial cells and inhibition of bursal lymphopoiesis.

Ultrastructure of Feline Mammary Hypertrophy

The ultrastructure of feline mammary hypertrophy was studied in a five-month-old female which had aborted recently, a ten-year-old female which was one month postestrus, and a four-year-old progestin-treated neutered male. Morphologic comparisons were made to normal mammary tissue from a one-year-old female cat. Hypertrophied mammary tissue had the same cell types and spatial relationships as did the normal gland. Major differences included a more highly developed duct system composed of metabolically active cells which often were arranged in multiple cell layers, and periductular stroma with increased fibroblasts and vascularization. Hypertrophied epithelial cells were characterized generally by smooth-contoured nuclear membranes, more evenly dispersed heterochromatin, prominent nucleoli, increased polyribosomes, and elongated mitochondria. Secretory activity was developed significantly only in the cat that had aborted recently. Modifications in myoepithelial cells included: more evenly dispersed nuclear heterochromatin, thicker bundles of cytoplasmic filaments, more straight plasma membranes along the basal lamina, and elongated hemidesmosomes. Multilayering of the basal lamina was accentuated. Stromal fibroblasts had nuclear heterochromatin distributed similarly to that of epithelial and myoepithelial cells, and increased rough endoplasmic reticulum. Myoepithelial cells did not contribute to the increased stromal cellularity. No significant ultrastructural differences were noted between mammary hypertrophy in young, old, and progestin-treated cats.

Morphology of the Epididymal Region of Turkeys Producing Abnormal Yellow Semen

Male turkeys producing abnormal yellow-colored semen (YS) had hypertrophied epithelial cells in the ductuli efferentes. The cells were engorged with cytoplasmic, lipid-like (lipoid) droplets, a morphological abnormality found exclusively in this area of the epididymal region. The testes, epididymal region, ductus deferens, and abdominal fat were relatively yellow compared to turkeys producing normal white semen (WS). Adipose tissue within the abdominal cavity and lining the ductus deferens was more abundant in the YS producers.In addition to increased lipoid droplets, nonciliated cells of the ductuli epithelia contained larger and more numerous electron-dense lysosomal bodies than similar nonciliated cells in WS males. Resorption of morphologically normal and abnormal spermatozoa by the epithelia of the ductuli efferentes was prevalent in the YS males but was not observed in the WS turkeys. The seminal fluids in the epididymal region of the YS males contained abnormal spermatids, cellular debris, and increased amounts of electron-dense proteinaceous material.

Agonistic and antagonistic effects of clomiphene citrate and its isomers.

The agonistic and antagonistic properties of clomiphene citrate (CL) and its isomers were examined in the rat uterus. Immature rats (21 days old) were injected with various doses of estradiol benzoate (EB), CL, zuclomiphene (ZUC, cia isomer), and enclomiphene (ENC, trans isomer), and uterine weight or epithelial cell height was measured. EB treatment produced a typical doseresponse curve for uterine weight with a steep slope, while the curves resulting from treatment with CL, ZUC, or ENC were attenuated with a very shallow slope. These differences in shapes of the dose-response curves render the determination of relative potency estimates inaccurate and misleading. In contrast, the shapes of the dose-response curves for epithelial cell hypertrophy were similarforallfour compounds. EB was more potent than any form of clomiphene;however,the maximum extent of cellular hypertrophy was not as great. The half maximal dose for each compound was EB, 0.35 ± 0.04 Mg; ENC, 25.0 ± 2.0 Mg; CL, 35.0 ± 3.1 Mg; and ZUC, 65.0 ± 7.1 ug. The ability of these drugs to antagonize the action of EB was examined by injecting EB plus CL, ZUC, or ENC and measuring the uterine weight or epithelial cell hypertrophy 72 h later. All three forms of the drug were antagonistic to EB-induced uterine weight gain over the same dose ranges in which they were agonistic by themselves. No antagonistic effects were observed on estradiol stimulation of epithelial cell hypertrophy. These data show that CL and its isomers are fully capable of stimulating epithelial cell hypertrophy in the rat uterus, and thus, valid relative potency estimates can be obtained with this response. This is not true when uterine weight gain is used because differential cell stimulation is not taken into account. In addition, CL and its isomers are agonistic and antagonistic over the same dose ranges when uterine weight gain is used; however, no antagonism of estrogen-stimulated cellular hypertrophy is measured. Therefore, broad generalizations concerning the estrogenicity or antiestrogenicity of these compounds are not warranted and can be made only when specific endpoints are evaluated.

Stimulatory and inhibitory effects of estrogen and antiestrogen on uterine cell division.

Acute administration of 17 beta-estradiol or the antiestrogen nafoxidine to immature rats produces quantitatively similar responses in the uterine stroma and myometrium, although the responses to nafoxidine occur at slightly later times. Both the hormone and drug cause nuclear translocation of equivalent amounts of estrogen receptor in these two cell types, although receptor translocation is slower with nafoxidine, and nuclear receptor levels remain elevated for an extended time. Based upon labeling and mitotic indices, however, the response of the luminal epithelium to a maximum dose of nafoxidine is much lower than that produced by estradiol, although nafoxidine treatment causes massive hypertrophy of luminal epithelial cells and causes nuclear translocation of estrogen receptors in this cell type. If nafoxidine is administered 30 min after administration of estradiol, cell division in the luminal epithelium is inhibited. Furthermore, multiple injections of estradiol itself within a 24-h period decrease cell division in the luminal epithelium relative to controls receiving a single injection of the hormone. These results indicate that estradiol and the antiestrogen can have both inhibitory and stimulatory effects on the luminal epithelium and that cell division in different uterine cell types can be differentially affected.

Development of Amphibian Thymus. II. Sequential Occurence of Two Epithelial Cell Types in the Urodele Pleurodeles Waltlii.

Sequential occurence of epithelial cell types was studied at the ultrastructural level during ontogenesis in the urodele amphibian Pleurodeles waltlii. From stage 38 to 42, reticular epithelial cells -orma network, the meshes of which are filled by free recently infiltrated lymphoid stem cells. From stage 43 to 45, numerous contacts between reticular cells and differentiating lymphocytes are observed. At stage 56, reticular cells show typical aspects of dense reticular cells, their long cytoplasmic processes enclosing numerous dividing lymphocytes. At stage 53, highly secreting and clustered hypertrophic epithelial cells differentiate. Their secretory products are found in large vacuoles or cysts. Dense reticular cells may play a role in situ in lymphocyte blastic transformation and multiplication. Hypertrophic epithelial cells may secrete humoral factors acting at the peripheral level for subsequent T cell maturation.

Pathological changes in rats fed the Crambe meal-glucosinolate hydrolytic products, 2S-1-cyano-2-hydroxy-3,4-epithiobutanes (erythro and threo) for 90 days.

2S-1-Cyano-2-hydroxy-3,4-epithiobutanes (erythro and threo) isolated from the seed of Crambe abyssinica, were fed to groups of six weanling rats at levels of 0, 75, 150 or 300 ppm in the diet for 90 days. The higher dose groups showed poor growth and increased serum levels of alkaline phosphatase, total bilirubin, glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase and ornithine carbamyl transferase. The severity and occurrence of renal and hepatic lesions were dose-dependent. Renal alterations consisted of hypertrophy of proximal tubular epithelial cells with prominent karyomegaly. Hepatic lesions consisted primarily of megalocytosis of the hepatocytes and bile-duct hyperplasia with disruption of the normal hepatic architecture. Half of the rats in the high-dose group had karyomegaly of pancreatic acinar cells.

Reversal by Testosterone of Atrophy of Accessory Genital Glands of Castrated Male Sheep

The histologic features of male accessory genital glands of entire sheep (group I), castrated sheep (group II), castrated sheep treated with 40 daily intramuscular injections of 50 milligrams testosterone propionate (group III), and castrated sheep treated with 600 milligrams testosterone propionate 72 hours before death (group IV) were compared. Sheep were castrated at 3 months old and all sheep were killed when 15 months old. Volume fractions of glandular tissue, intralobular fibromuscular tissue and perilobular fibromuscular tissue of the seminal vesicles and Cowper's glands fluctuated significantly (P less than 0.05) during postcastration atrophy and after repeated testosterone treatment. Atrophy in sheep in group II was least in the prostate but greatest in Cowper's glands, seminal vesicles and ampullae of vasa deferentia. Seminal vesicle plexi, whose cytons had a statistically significant (P less than 0.05) degree of shrinkage, also were atrophied. After treatment with testosterone the postcastration atrophy of plexal neurons was almost reversed in sheep in group III. There also was hypertrophy of epithelial cells but the testosterone treatment failed to reduce to normal the fibromuscular volume fraction of the accessory genital glands. Testosterone propionate treatment of sheep in group IV failed to elicit appreciable morphologic changes. These results are compared with our previous findings on the content and uptake of zinc by the accessory genital glands. It is suggested that accumulation of zinc in the accessory genital glands of sheep is not necessarily closely linked to normal histologic appearance.

An inhalation toxicity study of chlorine in Fischer 344 rats following 30 days of exposure

A subacute study was completed in groups of 10 male and 10 female Fischer 344 rats exposed to air (controls), 1, 3, or 9 ppm chlorine for 6 hr/day, 5 days/week, for 6 weeks. Concentration related decreases in body weight gain were seen at all exposure concentrations in females and at 3 and 9 ppm in males. Additionally, three females at 9 ppm died before the end of Day 30 of exposure. Urinalysis, hematology, and clinical chemistry evaluations were completed on the surviving animals. The urine specific gravity was elevated at all exposure concentrations in the females and at 3 and 9 ppm in the males. The hematocrit and white blood cell count were increased in the females exposed to 9 ppm. Elevations in alkaline phosphatase activity, blood urea nitrogen, γ-glutamyl transpeptidase, and serum glutamic-pyruvic transaminase occurred at 9 ppm; alkaline phosphatase was elevated at 3 ppm in rats of both sexes. Widespread evidence of inflammation was seen throughout the respiratory tract with hyperplasia and hypertrophy of epithelial cells of the respiratory bronchioles, alveolar ducts, and alveoli of male and female rats exposed to 9 ppm. Changes in male rats at 3 or 1 ppm consisted of focal inflammation of the nasal turbinates and a slight to moderate inflammatory reaction around the respiratory bronchioles and alveolar ducts. Increased eosinophilic cytoplasmic homogeneity and decreased granularity of the epithelial cells of the proximal convoluted tubules were seen in the kidneys of male rats exposed to 9 ppm. The livers of rats of both sexes at 9 or 3 ppm had an increased hepato-cellular cytoplasmic vacuolation. These data indicated that repeated exposure of Fischer 344 rats to chlorine resulted in pulmonary effects at all levels of chlorine used, and hepatic and renal effects at 9 and 3 ppm.

Electron microscopic observations of renal lesions caused by lithium carbonate: Hypertrophy of endothelial and epithelial cells

The effects of lithium carbonate on the ultrastructure of the rat kidney were studied. Fifteen male rats of the Sprague-Dawley strain were given aqueous lithium carbonate by mouth, 74mg/kg/day. These rats were killed on days 5, 10 and 15. Six control rats were given NaCl solution equivalent in volume and tonicity to the lithium dosage. Blood analyses were performed on both experimental and control animals. Test animals with a serum level of 0.5mEq/L showed marked hypertrophy of endothelial and epithelial cells in the glomeruli. The capillary lumens and urinary spaces were almost completely occluded by these enlarged cells. Among the prominent features of these cells were the hypertrophy of the Golgi apparatus and an increase in the rough endoplasmic reticulum. Similar proliferation of the Golgi apparatus was also observed in the epithelial cells of the proximal, distal and collecting tubules.

The effect of dietary vitamin A on NO 2 exposure on the hamster lung

The effect of dietary vitamin A and NO 2 exposure on the hamster lung was evaluated by histopathology, electron microscopy, and thymidine uptake studies. Hamsters were maintained on deficient (0 μg), adequate (100 μg), and high (200 μg) dose levels of vitamin A while being exposed repeatedly to 10 ppm of NO 2 for 5 hours once a week over an 8-week period. Hamsters of the deficient group exhibited clinical and morphologic changes characteristic of vitamin A deficiency. Animals maintained on adequate and high dose levels of vitamin A were not affected by vitamin A deficiency. Hypertrophy and hyperplasia of the epithelial cells of the terminal bronchiolar alveolar region of lungs of adequately and highly dosed animals were greater than those observed in the deficient animals, when NO 2 exposure was given. However, the extent of the lesions observed in all three groups was less than that seen in normal hamsters given a single, 5-hour NO 2 exposure. Ultrastructural changes observed in vitamin A-deficient hamsters exposed to NO 2 were hypertrophy and hyperplasia of bronchiolar epithelial cells, diffuse loss of cilia, membrane damage, and mitochondrial damage manifested by calcium deposition. Tritiated thymidine uptake studies of lungs of animals exposed repeatedly revealed a rather erratic cell renewal pattern following NO 2 exposure in comparison to the group of animals exposed singly.

Synthesis and migration of glycoproteins in cells of the rat thymus, as shown by radioautography after 3H-fucose injection.

Young male rats received a single intravenous injection of 3H-fucose and were killed after various time-intervals. Light- and electron-microscopic radioautographic studies of the thymus in animals killed shortly after injection showed that all of the different cell types present incorporated 3H-fucose label. The heaviest uptake occurred in macrophages and in hypertrophic epithelial cells located near the cortico-medullary border. Somewhat lighter incorporation was observed in medullary and cortical stellate epithelial cells and in cells designated as special cells, while the lightest reaction appeared over lymphocytes. In all cells the label was localized initially to the Golgi apparatus, where, presumably, it was incorporated into glycoproteins. With time, some of the labeled putative glycoproteins in all cell types migrated to the plasma membrane. In macrophages, much of the label migrated to lysosomal bodies, while in the special cells the label migrated to dense bodies which may also be of lysosomal nature. In stellate and hypertrophic epithelial cells much of the label migrated to characteristic vacuoles. The possible relationship between the observed glycoprotein synthesis in these cells and hormone production is discussed.

Role of estrogen receptor binding and transcriptional activity in the stimulation of hyperestrogenism and nuclear bodies.

The effects of estradiol and nafoxidine on nuclear estrogen receptor binding, RNA polymerase activities, and uterine ultrastructure were studied. Animals were either injected with estradiol, implanted with estradiol/paraffin pellets, or injected with nafoxidine. Animals treated with nafoxidine or estradiol implants showed sustained long-term nuclear retention of estrogen receptor and increased nuclear RNA polymerase activities for up to 72 hr. A single injection of estradiol caused initial increases in these variables which returned to control levels by 24 hr after hormone treatment. Uterine tissue was examined by light and electron microscopy 72 hr after hormone treatments. Uteri from eith estradiol-implanted or nafoxidine-treated animals showed markedly increased hypertrophy of the luminal epithelial cells. Nuclei in sections of the uteri of these hyperestrogenized animals displayed a large number and wide array of nuclear bodies composed of a filamentous capsule and granular cores. We conclude that hyperestrogenization, a condition that eventually results in abnormal cell growth, is correlated with increased and sustained nuclear binding of the estrogen receptor, increased and sustained RNA polymerase activity, and the appearance of nuclear bodies.

The effect of prolonged Kale feeding on the thyroid glands of sheep

Four groups of sheep were fed the following rations: Group I Kale ad lib., Group II Kale ad lib.+0·22 kg. blood meal/flaked maize mixture, Group III Kale ad lib.+0·22 kg. blood meal/flaked maize mixture and 10 mg. Kl weekly by mouth, Group IV 0·9 kg. hay+0·22 kg. blood meal/flaked maize mixture. They were fed these rations for 17 weeks when the sheep were killed. The thyroids were removed, weighed and pieces were taken for histological examination. The kale had a goitrogenic effect which was overcome by the iodine supplementation. The group receiving kale showed only a three-fold increase in thyroid weight whereas the group receiving the blood meal/flaked maize mixture in addition to the kale showed a six-fold increase in weight. The mixture had no goitrogenic effect when fed without kale to the control group. The mixture appears to increase the goitrogenicity of the kale. The histology shows considerable hypertrophy of follicular epithelial cells and a diminution in colloid and this accounts for the weight incrase of the glands.

Evaluation of the role of oestrogen contamination in functional studies with uterine RNA from oestradiol-treated rats.

Numerous studies have shown that uterine RNA obtained from oestradiol stimulated rats (U-RNA) reproduces the effects of oestradiol on the uterine epithelium of spayed rats. The present work was aimed at clarifying whether oestrogen contamination of the RNA preparations could be responsible for the hormone- like effects. U-RNA and vaginal RNA were prepared from rats treated with 10 μg of oestradiol-17β-6.7-3H. These labelled RNA preparations were then assayed for oestrogen contamination and for their biological activity in the uterine horn of spayed rats. The following observations were made: 1. U-RNA and vaginal RNA preparations were contaminated with tritium label. Assuming that this is all in the form of oestradiol, U-RNA would contain 5.10-7 μg oestradiol/100 μg RNA, and vaginal RNA 6.10-7 μg/100 μg RNA. 2. In biological tests, U-RNA only was active in stimulating hypertrophy of the luminal epithelial cells. This activity was lost after treatment of the U-RNA with ribonuclease. 3. Intraluminal administ...

The cellular site of virus replication in the intestine of chicks infected with an avian adenovirus.

The terminal ileum from 10 chicks infected orally with strain 93 avian adenovirus and 5 uninfected chicks were examined by the fluorescent antibody technique and conventional histologic methods. In the infected birds, cells containing viral antigen were scattered, relatively few in number, and present only in the epithelial layer forming the surface of the villi. Both columnar and goblet cells were infected. Neither clusters of infected cells nor contiguous infected cells were observed. On stained sections examined with the light microscope, hypertrophied epithelial cells containing nuclear inclusions were seen to have essentially the same sparse and scattered distribution as cells containing viral antigen as shown by fluorescence techniques. The overall architecture of the epithelium was normal and no lymphoid hyperplasia or inflammatory reaction was present. The fluorescent antibody localization and inclusions implicate the nuclei of epithelial cells as the site of viral replication in the intestine with the particular model employed.

魚類における蛋白同化ステロイドの成長促進効果に関する生理学的研究-I

It is recognized that the growth rate of the goldfish treated with 4-Cl was about two times higher than that of the control, and the optimum dose for the sish was 0.5mg per fish in both sexually active and inactive seasons. Such and effective anabolic action was not recognized in the case of MAD and T. P. mainly because of strong secondary effects of these steroids. Renotrophic action and suppresseve one to gonadal maturation were also observed in the case of 4-Cl. 4-Cl has the renotrophic action, i. e. hypertrophy of epithelial cells and thrir nuclei of kidney tubules. However, in fish unlike in rat, this action is not available as an index of bioassay of anabolic action. The supperssive action of 4-Cl to gonadal maturation in the goldfish is chiefly attributable to inhibition of yolk deposition in the oocytes.

The fine structure of compensatory growth in the rat kidney after unilateral nephrectomy

AbstractThe structural changes in the nephrons of the rat kidney during compensatory growth were observed for 96 hours following unilateral nephrectomy. Hypertrophy of tubular epithelial cells involves dilation of the cisternae of rough endoplasmic reticulum, proliferation of Golgi membranes and agranular reticulum, and increase in number of cytoplasmic ribosomes. The appearance of absorption droplets and microtubules, that are polarized along the cell axis, coincides with maximal hypertrophy of proximal tubule cells. Premitotic dedifferentiation of these cells involves flattening of the basal infoldings of the plasmalemma, decrease in number and disorientation of mitochondria, loss of apical compartments, and the reduction in number of microvilli. Cilia appear on the apical borders of some cells. Bundles of 30–50 Å filaments occupy the cytoplasm at the base of proximal tubule cells.In distal tubule cells that are undergoing mitosis, numerous mitochondria remain intimately associated with infoldings of the basal plasmalemma. This persistence of the differentiated basal region prevents complete cell division, and binucleate and multinucleate cells arise as a result of failure of cytoplasmic cleavage after normal karyokinesis. During mitosis, the chromosomes and apical vesicles are restricted to organelle‐free masses of cytoplasm that project into the lumen.In collecting tubules, both intercalated and lining cells undergo mitosis during compensatory growth. By 72 hours, a less differentiated cell type, that is active mitotically, appears in the cortical portion of collecting tubules. The number of binucleate epithelial cells increases in the compensating kidney tubules. Unilateral nephrectomy also induces distinct alterations in the fine structure of the glomerulus and the papilla of the contralateral organ.