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Tokuma Yanai Haruaki Taniguchi Hiroki Sakai Kazunori Yoshida Naoto Kimura Akira Katou Yuji Oishi Toshiaki Masegi 《Journal of medical primatology》1996,25(4):309-312
Abstract: A rare case of bilateral adrenal myelolipomas in a female cotton-top tamarin is reported. Large bilateral masses in the adrenal glands were composed of mature adipose cells containing varying amounts of hematopoietic cells of the myeloid, erythroid, and megakaryocyte series. The gross and histologic features of this case closely resemble human “giant” adrenal myelolipomas. 相似文献
84.
Kohtaro Asayama Kazushige Dobashi Yasusuke Kawada Takaya Nakane Akira Kawaoi Shinpei Nakazawa 《The Histochemical journal》1996,28(1):63-71
Summary To quantitate the developmental changes in selenium-dependent cellular glutathione peroxidase during the perinatal period,
tissue sections from foetal (day 12 to day 22) and neonatal (day 6) rats were stained immunohistochemically using specific
polyclonal antiserum. The intensity of the staining was quantified by fluorescence microscopy image analysis. There was a
general trend of enriched glutathione peroxidase in the epithelial linings and metabolically active sites. Significant fluorescence
was detected in cardiomyocytes, hepatocytes, renal tubular epithelium, bronchiolar epithelium and intestinal epithelium at
day 15. The intensity increased in a stepwise manner therafter. The overall increase in the intensity of staining in the heart,
liver, kidneys, lungs and intestine was 1.5-, 2.3-, 1.6-, 1.7- and 3.0-fold, respectively. The phase of most rapid increase
occurred during the foetal period in the liver, intestine and heart. In the kidneys and lungs, glutathione peroxidase increased
significantly during foetal life, and to a similar extent postnatally. These results suggest that the intracellular H2O2-scavenging system develops during the foetal period as an essential mechanism for living under atmospheric oxygen conditions.
The late development observed in the kidneys and lungs is consistent with the relative biological immaturity of these organs
in full-term neonates. 相似文献
85.
Eiji Matsui Masanori Hoshino Akiko Matsui Akira Okahira 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1995,668(2)
High-performance liquid chromatography with a successive column-switching technique was developed for simultaneous determination of citalopram and its four metabolites in plasma. Plasma samples were injected directly, and the target compounds were purified and concentrated with an inexpensive commercial octadecyl guard column. Then, the six-port valve was switched, and the compounds retained in the column were eluted by the back-flush method using 20 mM phosphate buffer (pH 4.6)-acetonitrile (70:30, v/v) containing 0.1% diethylamine and separated with an ODS column. The compounds were assayed with a fluorescence detector at an excitation wavelength of 249 nm and an emission wavelength of 302 nm. At least 30 plasma samples could be treated with an octadecyl guard column. The limits of quantitation of this method were 2.0 ng/ml for citalopram, desmethylcitalopram, didesmethylcitalopram, citalopram propionic acid and citalopram N-oxide. This method was applied to a pharmacokinetic study in dogs and a toxicokinetic study in rats. 相似文献
86.
87.
Akira Akabayashi C.T.B.V. Zaia James I. Koenig Steven M. Gabriel Ivan Silva Sarah F. Leibowitz 《Peptides》1994,15(8):1437-1444
The peptide galanin (GAL), when injected into the rat hypothalamus, is known to stimulate feeding behavior and affect the secretion of various hormones, including insulin and the adrenal steroid, corticosterone. To determine whether endogenous peptide levels shift in relation to natural rhythms of feeding and circulating hormone levels, rats were sacrificed at different times of the light/dark cycle, and their GAL levels were measured, via radioimmunoassay, in medial hypothalamic dissections and micropunched hypothalamic areas. The results suggest the existence of two distinct diurnal rhythms for hypothalamic GAL. One rhythm, detected exclusively in the area of the SCN, is characterized by bimodal peaks of GAL, threefold higher than basal peptide levels, around the onset of the dark and light periods. The second rhythm shows a single peak of GAL towards the middle of the nocturnal feeding cycle, specifically between the third and sixth hour. This latter rhythm is evident in the dorsal region of the medial hypothalamus, localized specifically to the lateral portion of the PVN. Moreover, it is inversely related to circulating insulin but unrelated to the adrenal steroids, suggesting a possible association between this pancreatic hormone and GAL in the PVN. 相似文献
88.
Yukio Katori Tomonori Takasaka Makoto Ishikawa Akira Tonosaki 《Cell and tissue research》1994,276(2):245-252
The surface coat, ciliary process, and microvilli of the lamprey neuromast were examined with electron microscopy after tannic acid prefixation and lectin histochemistry. The neuromast was found to exist in the form of a dermal mound with a furrow in the middle. On the bottom of the furrow, the hair cell was characterized by a kinocilium and 15–20 stereocilia, arranged along the longitudinal axis of the furrow. Spanning structures were demonstrated between the kinocilium and stereocilia as well as between stereocilia. The surface coat, enhanced by tannic acid prefixation, was particularly rich over the surface of the supporting cell; by contrast, it was thin over the hair cell. Some lectins (PNA, GS-I, SBA, WGA) showed affinity to the surface coat of the supporting cell as well as the hair cell, and the others (RCA-I, MPA, ConA) showed affinity only to the supporting cell. These differences in the structure and affinities of the surface coat suggest an extracellular milieu highly specialized for the hair cell in this particular form of the mechanoreceptor. 相似文献
89.
Expression of β-actin and β-tubulin mRNA was examined in androgen-sensitive motoneurons of the spinal nucleus of the bulbocavernosus (SNB) in adult male rats by in situ hybridization histochemistry using complementary DNAs encoding chick β-actin and mouse β-tubulin, respectively. Both hybridizable β-actin and βtubulin mRNAs were localized in the somata and proximal dendrites of SNB motoneurons. Removal of androgen by castration significantly reduced the expression levels of both β-actin and β-tubulin mRNAs in the SNB motoneurons, whereas the changes were prevented by testosterone treatment. In contrast, castration or testosterone treatment induced little or no change in the expression levels of these mRNAs in the much less androgen-sensitive motoneurons of the retrodorsolateral nucleus (RDLN). These results suggest that androgen regulates the expression of β-actin and β-tubulin genes in the SNB motoneurons and may provide evidence for the molecular mechanisms of hormonally induced neuronal plasticity in the SNB motoneurons. 相似文献
90.
Characterization of Low pH-induced Catecholamine Secretion in the Rat Adrenal Medulla 总被引:1,自引:0,他引:1
Abstract: Catecholamine (CA) secretion was evoked when the isolated rat adrenal gland was perfused with HEPES-buffered Krebs solution acidified by the addition of HCI or by gassing with 95% O2/5% CO2. The secretion was detectable at pH 7.0 and increased with decreasing pH until at ~6.4. The low pH-induced CA secretion consisted of two phases, an initial transient response followed by a sustained phase. An intracellular Ca2+ antagonist, 3,4,5-trimethoxybenzoic acid 8-(N,N-diethylamino)octyl ester, selectively inhibited the initial phase of secretion. Both of the responses were resistant to nifedipine, a blocker of voltage-gated Ca2+ channel, but were completely inhibited in Ca2+-free (1 mM EGTA containing) solution. Adrenaline was an exclusive component in CAs released by low pH. The time course and extent of intracellular acidification caused either by low pH in the external medium or by the offset of a transitory NH4CI application had no correlation with those of the secretory responses in the corresponding period. These results suggest that extracellular acidification preferentially activates adrenaline secretive cells to evoke CA secretion and that this low pH-induced CA secretion may be mediated by dihydropyridine-insensitive Ca2+ influx. Furthermore, the initial transient phase of the low pH-induced CA secretion might be caused by a Ca2+ release from intracellular stores, which is also induced by the Ca2+ influx. 相似文献