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541.
O Nada  K Hirata 《Histochemistry》1976,50(2):111-117
The foliate, vallate and fungiform papillae of the rabbit's tongue were studied fluorescence-histochemically under normal and experimental conditions. In normal animals a yellow fluorescence suggesting the presence of a serotonin-like monoamine was demonstrated only in taste bud cells of the foliate papilla, though its intensity was very weak. The fluorescence disappeared completely following reserpine treatment, while it was significantly enhanced by the treatment with nialamide. The fluorescence of taste bud cells could be clearly distinguished from that of catecholamines by the treatment with alpha-MMT followed by nialamide. When 5-HTP, 5-HT and 5,6-DHT were administered separately, each of these drugs was selectively taken up in taste bud cells of the foliate and vallate papillae, but no fluorescent cells were observed in the fungiform papilla. From the present results, it seems reasonable to conclude that the fluorigenic amine of taste bud cells may be 5-HT (serotonin), or at least an indoleamine derivative. Also, it is suggested that the taste bud of the vallate papilla contains a cell type which can potentially synthesize a biogenic amine in situ, or is actually synthesizing it in a very small amount just like in the case of the taste bud of the foliate one.  相似文献   
542.
A new approach has been developed and used to minimize the timeand more carefully monitor and control the seed-train expansionprocess of recombinant mammalian cell lines. The process uses 50or 100 ml cryo-bags that contain frozen cells at high cell densities of 20 × 106 ml-1 (100 ml bags) or 40 × 106 cells ml-1 (50 ml bags). The frozen bag cell suspension is thawed and transferred directly into a bioreactorthat has been modified such that pH, DO and temperature can becontrolled at the initial volume of two liters (the working volume eventually increases to 12 l). The successful use of thesecryo-bags and the modified `inoculation' bioreactor to initiate anew seed train expansion of rBHK or rCHO cells is described herein. The interval between cell thawing and the accumulation ofsufficient cell mass to inoculate a production reactor is reducedby at least 25 to 30 days compared to the conventional method that begins with the thaw of 1–2 ml cryo-vials. This `one-step'technology leads to a much more consistent scale-up by reducingmanual operations and avoiding subjective decisions during the scale-up phase. The cell metabolic rates and product integritywere similar to the control experiments. Furthermore, it was found that it is not necessary to include a wash step to removeDMSO prior to the inoculation.  相似文献   
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Summary— Zebrafish hepatocytes respond to stimulation with estradiol 17β (E2) with an extreme enlargement of the endomembrane system, especially the endoplasmic reticulum (ER), and when stimulation is stopped with a rapid degradation of enlarged endomembranes. Two pathways for degradation of ER were studied: a) the autophagy which was evaluated by stereological measurement; and b) the activity of cytosolic phospholipase B (PL-B) measured by a titration method. After a 30-day treatment with E2 a six-fold increase of the surface density of ER was accompanied by an increase of both autophagy and PL-B activity. 2 days after stopping the stimulation with E2 the ER vesiculated and its surface density decreased to the half value. Interestingly, at the same time autophagic vacuoles (AV) almost disappeared from hepatocytes, while the activity of PL-B reached its maximum at which it persisted for a further 4 days. After 4–6 days without E2 the cistern of ER became flattened again and new AVs reappeared. The data suggest that the regulation mechanisms of endomembrane degradation by PL-B and autophagy do not depend on each other and also that the appearance of AV is strongly related to the shape of ER.  相似文献   
545.
Effects of suckling on the structure of mammotrophs and the release of prolactin, were studied in rats on the 10th day of lactation with the use of electron microscopy and radioimmunoassay techniques. Nursing animals were separated from their young for 8 hr and subsequently united and permitted to nurse for 1, 5, 15, 30 min; or 1, 2 and 4 hr. Blood samples were obtained prior to and throughout the suckling interval and pituitary glands were processed for electron microscopy. Control animals consisted of normal lactating females and animals separated from their young for 8 hr. Normally lactating controls had high prolactin serum levels (501 +/- 95 ng/ml) and synthetically active appearing mammotrophs. An 8 hr separation from the pups induced a dramatic lowering of serum prolactin (32 +/- 5 ng/ml), an increase in secretory granule storage, and a great dilation of rough endoplasmic reticulum (RER) cisternae. Five min of renewed suckling resulted in a rise of plasma prolactin levels (605 +/- 183 ng/ml) which remained high thereafter. The major ultrastructural changes observed during the first 30 min of suckling were as follows: 1) at 1 min, the RER became cmone?); 2) AT 5 MIN, AND MUCH MORE OBVIOUSLY AT 15 AND 30 MIn, a massive discharge of secretory granules was observed; and 3) at 15 min, the collapsed RER underwent transformation for 1,2 and 4 hr) induced new hormone synthesis as suggested by the presence of hypertrophied Golgi elements and numerous immature granules. This was accompanied by a new transformation of the RER from the vesicular into a lamellar form now consisting of very slender cisternae lined with numerous ribosomes, presumably involved in the renewal of the synthetic process. The morphologic findings described correlate well with the time table of prolactin release. In addition, the dramatic early changes in the structure of the RER suggest a possible involvement of this organelle in the storage and release of a proposed rapidly releasable pool of prolactin.  相似文献   
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Summary A specific formaldehyde-induced yellow fluorescence, suggesting the presence of serotonin-like monoamine has been demonstrated in the gustatory cells of the frog.The fungiform papillae of frogs were examined fluorescence-histochemically after intraperitoneal injection of 5,6-dihydroxytryptamine. The results indicated that the fluorophore of gustatory cells was affected selectively by the drug injection: the yellow fluorescence was transiently enhanced 3 hours after the drug injection, thereafter being reduced rapidly. The effect of 5,6-dihydroxytryptamine was long-lasting with the reduction of the yellow fluorophore persisting at least for the experimental duration of 14 days. A single injection of 6-hydroxydopamine induced a complete depletion of noradrenaline fluorescence from adrenergic nerve terminals, while the fluorescence of gustatory cells was not affected by a high dose of the drug.The present results with pharmacologic treatments further support the view that the gustatory cell of the frog contains a serotonin-like monoamine.  相似文献   
550.
Summary Three kinds of nucleoside phosphatases were demonstrated histochemically in the cat carotid body with nucleoside triphosphate, nucleoside disphosphate and nucleoside monophosphate as substrates. Each of these enzyme activities exhibited the substrate specificity respectively. The nucleoside triphosphatase activity showed specific localization in association with the parenchymal cells of the carotid body.The electronmicroscopy revealed that the reaction product was located on and between the two apposing plasma membranes of type I and type II cells, of a type II cell and its wrapping axons and of the intricate basal infolding of a type II cell itself.Some possible functions of the adenosine triphosphatase in the carotid body are discussed.  相似文献   
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