scholarly journals Induction of pinocytosis in rat hepatocytes by partial hepatectomy.

1977 ◽  
Vol 72 (3) ◽  
pp. 695-706 ◽  
Author(s):  
M Mori ◽  
A B Novikoff

Rat hepatocytes, normally not highly pinocytic cells, becomes so after partial hepatectomy when about two-thirds of the liver is removed. Droplets, up to 20 mum in diameter, develop, initially by addition to smaller pinocytic structures and later by fusion with lysosomes. The droplets contain a material with an electron microscope periodicity characteristic of fibrin; they are periodic acid Schiff-positive as is plasma. It is therefore reasonable to consider plasma glycoproteins to be major components of the droplets. The droplets are at all times membrane delimited, an observation possible only after perfusion fixation. The droplets are positive for three lysosomal hydrolases identified cytochemically: acid phosphatase, N-acetyl-beta-glucosaminidase, and beta-glucuronidase. From light and electron microscopy it is evident that these activities are acquired by fusion with lysosomes, mostly autophagic vacuoles and residual bodies both of which become very numerous after partial hepatectomy. Pinocytic structures are seen relatively infrequently in the hepatocytes of normal rats but a great many are present after partial hepatectomy. They are most easily observed if horseradish peroxidase (HRP) is intravenously injected before sacrifice and sections are incubated for HRP cytochemistry. The low dose of HRP employed (10 mg/100 g body weight) does not induce pinocytosis in controls, either untreated rats or rats subjected to laparotomy, including palpation of the liver. However, in partially hepatectomized rats even a much smaller dose of intravenous HRP (3.3 mg/100 g) visualizes the pinocytic structures in hepatocytes (coated vesicles, channels, cuplike bodies, and droplets). Kupffer cells pinocytose much HRP in both control and partially hepatectomized rats.

1966 ◽  
Vol 14 (12) ◽  
pp. 884-897 ◽  
Author(s):  
SERGEI P. SOROKIN

Lungs from marsupials, bats and rodents were studied by light and electron microscopy. In all three groups, the great alveolar cells exhibit similar morphologic and cytochemical characteristics. Cytoplasmic vacuoles seen in these cells by light microscopy correspond to cytosomes that are demonstrable in them by electron microscopy. Such cytosomes are osmiophilic, periodic acid-Schiff-positive and stainable with Sudan black after acetone extraction. After fixation in a mixture of aldehydes, followed by extraction in chloroform-methanol and postfixation in osmium tetroxide, cytosomes lose their osmiophilia. The cytoplasm of the great alveolar cell is notable for a loosely ordered granular endoplasmic reticulum, an extensive Golgi apparatus and numerous multivesicular bodies. Many forms transitional in appearance between multivesicular bodies and cytosomes are present. In these, osmiophilic matter occupies the intervesicular space. It is proposed that these bodies are the precursors of cytosomes. The cytosomes are interpreted to be products of the "lysosomal" system in this cell. Ultimately they are secreted onto the alveolar surface.


Author(s):  
S. Yamashiro ◽  
D. Wilson ◽  
J. St. George ◽  
D. Hyde ◽  
C. Plopper ◽  
...  

In the past, ozone inhalation studies have focused on the lower airways and lung parenchyma. The purpose of this study was to evaluate the effects of ozone on submucosal glands of upper airways. Six adult male bonnet monkeys were exposed to 0.64 ppm ozone continuously for 7 days, and three were exposed to chamber conditions without ozone. The animals were exsanguinated under barbiturate anesthesia. The trachea and lung were fixed by airway infusion of Karnovsky's fixative, which was adjusted to pH 7.4 and 440 milliOsmols. Sagittal sections of ventral trachea were embedded in glycol methacrylate and Araldite 502 for light and electron microscopy. One micrometer methacrylate sections were stained with Alcian blue-periodic acid Schiff (AB/PAS). Selected areas of Araldite-embedded tissue were sectioned for transmission electron microscopy, stained with uranyl acetate and lead citrate and examined with a Zeiss EM 10. Volume percentages of the lumen, granular and nongranular regions of fhe gland and the duct wall, respectively, were estimated by stereologic methods on AB/PAS stained sections.


Author(s):  
B. Giammara ◽  
T. Romaine ◽  
W. Ambrose ◽  
J. Hanker

Many variations of the periodic acid-Schiff(PAS) reaction have been utilized for electron microscopy based on the Gomori periodic acid-silver methenamine reaction (1) or the periodic acid-thiocarbohydrazide-osmium tetroxide(PATCO) reaction (2,3). These reactions are widely employed and have been very useful for the demonstration of one or more biomacromolecules or structures such as glycogen, basement membranes, reticular fibers or lipopolysaccharide. However, these reactions have various drawbacks such as complexity of methodology, ability to stain only a limited number of these components, or lack of adaptability for both light and electron microscopy. Our newly devised PATS reaction is relatively easy to perform. A full description of the details must await the outcome of a pending patent application. It consists essentially of a stepwise treatment of the sample with periodic acid, thiocarbohydrazide(TCH) and silver methenamine.


Author(s):  
B. Giammara ◽  
E.J. Burkes ◽  
R. Scruggs ◽  
G. Greco ◽  
P. Yates ◽  
...  

In a recent study of 400 subgingival plaque samples from over 110 adult periodontitis patients, spirochetes were the overwhelming microbial type, averaging about 45% of the microbial count. This finding supports earlier arguments that spirochetes are pathognomonic in periodontal disease. Other studies had shown clear-cut differences in the microbial composition of healthy and diseased subgingival sites — the proportion of spirochetes being significantly higher in the latter. Another study indicated that periodontal deterioration at these sites could be predicted better by increased proportions of motile rods and spirochetes than by clinical measurements. However, spirochetes of all sizes and species do not show the same degree of association with periodontal breakdown. Moreover, spirochetes are usually difficult to culture and stain; they are generally monitored by darkfield or phase contrast microscopy.The PATS reaction, a modified periodic acid-Schiff(PAS) reaction which deposits silver for light and electron microscopy appears to stain Gram(-) bacteria positively as well as neutrophils and activated macrophages. When studying the stained Gram(-) bacteria on coverslip smears of subgingival plaque or crevicular fluid samples of patients by light microscopy, varying numbers of intensely stained spirochetes of different sizes were observed (Figs. 1,2). More spirochetes were usually seen in samples from diseased sites. After drying replicate PATS-stained coverslips with hexamethyldisilazane they were sputter coated with gold, and. then examined by the SEI and BEI modes of scanning electron microscopy (Figs. 3-6). A permanent record of the proportions of large, medium and small spirochetes at each site could thus be obtained. Generally, greater numbers of gram negative bacteria including some spirochetes were stained in samples from diseased sites. At some sites, however, spirochetes were the predominant microbes in both crevicular fluid and subgingival plaque (Fig. 1).


1969 ◽  
Vol 43 (3) ◽  
pp. 575-603 ◽  
Author(s):  
Susan G. Langreth

Spermiogenesis in Cancer crabs was studied by light and electron microscopy. The sperm are aflagellate, and when mature consist primarily of a spherical acrosome surrounded by the nucleus with its short radiating arms. The acrosome forms by a coalescence of periodic acid-Schiff-positive (PAS-positive) vesicles. During spermiogenesis one edge of the acrosomal vesicle invaginates to form a PAS-negative central core. The inner region of the acrosome bounding the core contains basic proteins which are not complexed to nucleic acid. The formation of an elaborate lattice-like complex of fused membranes, principally from membranes of the endoplasmic reticulum, is described. These membranes are later taken into the nucleus and subsequently degenerate. In late spermatids, when most of the cytoplasm is sloughed, the nuclear envelope and the cell membrane apparently fuse to become the limiting boundary over most of the sperm cell. In the mature sperm the chromatin of the nucleus and arms, which is Feulgen-positive, contains no detectable protein. The chromatin filaments appear clumped, branched, and anastomosed; morphologically, they resemble the DNA of bacterial nuclei. Mitochondria are absent or degenerate in mature sperm of Cancer crabs, but the centrioles persist in the nucleoplasm at the base of the acrosome.


Author(s):  
Odell T. Minick ◽  
Hidejiro Yokoo ◽  
Fawzia Batti

Vacuolated cells in the liver of young rats were studied by light and electron microscopy following the administration of vitamin A (200 units per gram of body weight). Their characteristics were compared with similar cells found in untreated animals.In rats given vitamin A, cells with vacuolated cytoplasm were a prominent feature. These cells were found mostly in a perisinusoidal location, although some appeared to be in between liver cells (Fig. 1). Electron microscopy confirmed their location in Disse's space adjacent to the sinusoid and in recesses between liver cells. Some appeared to be bordering the lumen of the sinusoid, but careful observation usually revealed a tenuous endothelial process separating the vacuolated cell from the vascular space. In appropriate sections, fenestrations in the thin endothelial processes were noted (Fig. 2, arrow).


Author(s):  
D. E. Philpott ◽  
W. Sapp ◽  
C. Williams ◽  
Joann Stevenson ◽  
S. Black

The response of spermatogonial cells to X-irradiation is well documented. It has been shown that there is a radiation resistent stem cell (As) which, after irradiation, replenishes the seminiferous epithelium. Most investigations in this area have dealt with radiation dosages of 100R or more. This study was undertaken to observe cellular responses at doses less than 100R of X-irradiation utilizing a system in which the tissue can be used for light and electron microscopy.Brown B6D2F1 mice aged 16 weeks were exposed to X-irradiation (225KeV; 15mA; filter 0.35 Cu; 50-60 R/min). Four mice were irradiated at each dose level between 1 and 100 rads. Testes were removed 3 days post-irradiation, fixed, and embedded. Sections were cut at 2 microns for light microscopy. After staining, surviving spermatogonia were identified and counted in tubule cross sections. The surviving fraction of spermatogonia compared to control, S/S0, was plotted against dose to give the curve shown in Fig. 1.


1972 ◽  
Vol 11 (1) ◽  
pp. 249-260
Author(s):  
J. ALWEN ◽  
JENNIFER J. GALLHAI-ATCHARD

A method for preparing suspensions of adult rat hepatocytes suitable for maintenance in vitro is described. Cultures were established from the cell suspensions by the squash technique. Cells were examined by light and electron microscopy; histochemically for glycogen, bile, lipid and glucose-6-phosphatase; and by autoradiography for DNA, RNA and protein synthesis. Hepatocytes could be maintained in vitro for at least 3 days and began to aggregate after 1 day. Uridine and leucine were incorporated, but not thymidine. Cultures consisted mainly of hepatocytes, though reticulo-endothelial cells were sometimes present.


2018 ◽  
Vol 56 (2) ◽  
pp. 322-331
Author(s):  
Rani S. Sellers ◽  
S. Radma Mahmood ◽  
Geoffrey S. Perumal ◽  
Frank P. Macaluso ◽  
Irwin J. Kurland

Lipin-1 ( Lpin1)–deficient lipodystrophic mice have scant and immature adipocytes and develop transient fatty liver early in life. Unlike normal mice, these mice cannot rely on stored triglycerides to generate adenosine triphosphate (ATP) from the β-oxidation of fatty acids during periods of fasting. To compensate, these mice store much higher amounts of glycogen in skeletal muscle and liver than wild-type mice in order to support energy needs during periods of fasting. Our studies demonstrated that there are phenotypic changes in skeletal muscle fibers that reflect an adaptation to this unique metabolic situation. The phenotype of skeletal muscle (soleus, gastrocnemius, plantaris, and extensor digitorum longus [EDL]) from Lpin1-/- was evaluated using various methods including immunohistochemistry for myosin heavy chains (Myh) 1, 2, 2a, 2b, and 2x; enzyme histochemistry for myosin ATPase, cytochrome-c oxidase (COX), and succinyl dehydrogenase (SDH); periodic acid–Schiff; and transmission electron microscopy. Fiber-type changes in the soleus muscle of Lpin1-/- mice were prominent and included decreased Myh1 expression with concomitant increases in Myh2 expression and myosin-ATPase activity; this change was associated with an increase in the presence of Myh1/2a or Myh1/2x hybrid fibers. Alterations in mitochondrial enzyme activity (COX and SDH) were apparent in the myofibers in the soleus, gastrocnemius, plantaris, and EDL muscles. Electron microscopy revealed increases in the subsarcolemmal mitochondrial mass in the muscles of Lpin1-/- mice. These data demonstrate that lipin-1 deficiency results in phenotypic fiber-specific modulation of skeletal muscle necessary for compensatory fuel utilization adaptations in lipodystrophy.


2013 ◽  
Vol 4 (3) ◽  
Author(s):  
Poppy M Lintong ◽  
Carla F Kairupan ◽  
Priska L N Sondakh

Abstract: Gentamycin, a frequently used aminoglycoside antibiotics, has a nephrotoxic effect to human beings and animals. The purpose of this research was to find out the microscopic changes of wistar rat kidneys after gentamycin induction. This was an experimental study, using five adult wistar rats, divided into three groups. Group I was the control group; group II consisted of two rats, injected with gentamycin 0,3 ml/day (dose of 60 mg/kg body weight/day) intraperitoneally for seven days; and group III consisted of two rats, injected with gentamycin 0,3 ml/day intraperitoneally for 10 days. Group I and II were terminated at day-8, and group III at day-11. Their kidneys were processed for microscopic slides, stained with hematoxylin eosin and Periodic Acid Schiff. In microscopic evaluation, group II and III showed oedema, necrosis, apoptosis, and basal membrane destruction of tubular epithelial cells. Group III also showed fat vacuoles in these epithelial cells (macrovesicular fatty changes). Conclusion: wistar rats injected with gentamycin 60 mg/kg body weight/day for 7 and 10 days showed oedema, necrosis, apoptosis, and basal membrane destruction of tubular epithelial cells; and macrovesicular fatty changes after 10 days of gentamycin.Key words: gentamycin, necrosis tubular epithelial cells, fatty changesAbstrak: Gentamisin termasuk antibiotik golongan aminoglikosida berspektrum luas yang bersifat nefrotoksik terhadap manusia dan hewan. Tujuan penelitian ini untuk melihat perubahan mikroskopik struktur ginjal tikus Wistar setelah diberikan gentamisin. Metode penelitian eksperimental dengan menggunakan lima ekor tikus Wistar dewasa yang dibagi atas tiga kelompok. Kelompok I tanpa perlakuan; kelompok II terdiri dari dua ekor tikus perlakuan yang diinjeksi dengan gentamisin 0,3 ml/hari (dosis 60 mg/kgBB/hari) secara intraperitonial selama tujuh hari; dan kelompok III terdiri dari dua ekor tikus perlakuan yang diinjeksi dengan gentamisin 0,3 ml/hari secara intraperitonial selama 10 hari. Tikus Wistar kelompok I dan II diteminasi hari ke-8, sedangkan kelompok III diterminasi hari ke-11. Ginjal tikus kelompok I -III kemudian dibuat preparat histopatologik dengan pengecatan rutin hematoksilin eosin dan Periodic Acid Schiff (PAS). Hasil penelitian menunjukkan tikus Wistar perlakuan yang diberikan gentamisin 0,3 ml/hari selama 7 sampai 10 hari secara mikroskopik memperlihatkan pembengkakan, nekrosis, apoptosis, dan destruksi membrana basalis sel epitel tubulus; dan pada hari ke-10 terlihat vakuol-vakuol lemak pada sel epitel sehingga inti terdesak ke tepi (perlemakan makrovesikuler). Simpulan: pemberian gentamisin pada tikus Wistar dengan dosis 60 mg/kg BB/hari selama 7-10 hari menunjukkan pembengkakan, nekrosis, apoptosis sel epitel tubulus, dan membrana basalis tubulus rusak; dan setelah hari ke-10 juga terlihat perlemakan makrovesikuler.Kata kunci: gentamisin, nekrosis sel epitel tubulus, perlemakan makrovesikuler


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