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991.
Taichiro Goto Yajoi Katayama-Kumoi Masaya Tohyama Masao Yoshida 《Cell and tissue research》1992,267(2):215-222
Summary The distribution and development of serotonin-and RFamide-like immunoreactivities in the nervous system of Chaetognatha, Paraspadella gotoi, were examined in whole-mount preparations. In adults, a single serotonin-like immunoreactive (5HTLI) neuron and numerous RFamide-like immunoreactive (RFaLI) neurons were found in the central nervous system. Based on the structure of the fins, hooks, and eyes, seven postembryonic developmental stages were recognized. The most obvious features of the stages are: stage 1, newly hatched young; stage 2, elongation of a continuous lateral tail fin; stage 3, separation of the lateral and tail fins; stage 4, appearance of hooks; stage 5, pigmentation of eyes, stage 6, attachment by tail adhesive fins; stage 7, prey capture. Stage 1 did not show any immunoreactivity. The 5HTLI neuron first appeared at stage 4 and its axonal pathway became similar to the adult at stage 6. On the other hand, the RFaLI neurons appeared at stage 3 in the ventral ganglion. Some of their somata disappeared at stage 5 and the neuronal architecture resembled the adult at stage 7 although the RFaLI neurons in the cerebral ganglion were complete at the juvenile stage.We are sad to announce that Dr. M. Yoshida died on 29 October 1988 相似文献
992.
M. J. J. Gijbels F. van der Ham A. M. van Bennekum H. F. J. Hendriks P. J. M. Roholl 《Cell and tissue research》1992,268(1):197-203
Summary Normal epithelial cell differentiation is charactezied by the production of distinct cytokeratin proteins. It is well known that epithelia of several organs show squamous metaplasia in a vitamin A-deficient status. It is not yet known whether these histological changes are concomitant with a change in cytokeratin expression. Therefore, 3-week-old female rats (BN/BiRij) were fed a vitamin A-deficient diet for 8 weeks. The cytokcratin expression in epithelia of various organs was monitored immunohistochemically during the induction of vitamin A deficiency. Therefore, monoclonal antibodies specific for human cytokeratin 4, 5, 5+8, 7, 10, 14, 18 and 19 were used. In a normal vitamin A status, the distributional pattern for the different cytokeratins in rats was similar to that reported for human tissue. No change in cytokeratin expression was seen in trachea, skin, liver and colon at any time point studied. Squamous metaplasia in urinary bladder and salivary glands was observed after six weeks on the vitamin A-deficient diet. This was concomitant with a substitution of cytokeratins 4, 5+8, 7, 18 and 19 by cytokeratin 10. The latter cytokeratin is specific for keratinzed squamous epithelium. A change in cytokeratin expression was observed in bladder, ureter, kidney, salivary glands, uterus and conjunctiva before histological alterations appeared. In conclusion, the changes in cytokeratin expression observed under vitamin A deficiency in epithelia in vivo are in agreement with those described in other studies for epithelial cells in vitro. The changes in cytokeratin expression and the subsequent differentiation into squamous cells occurs in basal cells of the bladder but not in transitional cells. Furthermore, histological alterations are preceded by changes in cytokeratin expression indicating that vitamin A status controls cytokeratin expression in vivo. 相似文献
993.
Summary The fine structure of the main excretory duct epithelium of the male mouse submandibular glands was investigated by scanning and transmission electron microscopy. Three principal cell-types were observed: type I and II, and basal cells. This epithelium was characterized by the presence of intercellular canaliculi. Type-I cells were the most numerous. They had an abundance of mitochondria, well-developed Golgi apparatus, a few electron-lucent lipid-containing granules and poorly developed basal infoldings. These cells were also characterized by many glycogen granules throughout the cytoplasm and abundant smooth endoplasmic reticulum in the apical cytoplasm. Type-II cells were the second most numerous. Their most characteristic feature was the presence of abundant heterogeneous lipid-containing granules having acid phosphatase activity at the periphery. They were concentrated in the infra- and supranuclear cytoplasm. The granules may be derived from mitochondrial transformation and seem to be a special kind of secondary autolysosome. Type-II cells also contained abundant mitochondria throughout the cytoplasm, much smooth endoplasmic reticulum in the apical cytoplasm, a well developed Golgi apparatus adjacent to the heterogeneous lipid-containing granules and no basal infoldings. Basal cells were situated adjacent to the basal lamina. They had a large nucleus and the cytoplasm was filled with glycogen granules. 相似文献
994.
Motoki Tagami Kazuo Yamagata Hideaki Fujino Akiyoshi Kubota Yasuo Nara Yukio Yamori 《Cell and tissue research》1992,268(2):225-232
Summary In this study bovine aortic endothelial cells were co-cultured with astrocytes from fetal Wistar Kyoto rats. Endothelial cells growing on type-I collagen, development. Although some cells appeared to be mature, horseradish peroxidase penetrated within 1 min of incubation through the intercellular junctions of these endothelial elements maintained on type-I collagen. In contrast, endothelial cells on type-IV collagen, co-cultured with astrocytes, were well developed; their intercellular junctions were well established, and plasmalemmal vesicles reduced in number. As a result, horseradish peroxidase was unable to penetrate through the endothelial cells grown on type-IV collagen and co-cultured with astrocytes because of the reduced extent of the junctional and vesicular transport. These findings reveal that (1) type-IV collagen is essential for the differentiation of endothelial cells, (2) endothelial cell-astrocyte interactions occur during co-culture, and (3) endothelial permeability depends on astrocyte-produced factors, in addition to type-IV collagen. 相似文献
995.
Summary Mapping of monoaminergic systems in the brain of the newt Triturus alpestris was achieved with antisera against (1) thyrosine hydroxylase (TH), (2) formaldehyde-conjugated dopamine (DA), and (3) formaldehyde-conjugated serotonin (5-HT). In the telencephalon, the striatum was densely innervated by a large number of 5-HT-, DA-and TH-immunoreactive (IR) fibers; IR fibers were more scattered in the amygdala, the medial and lateral forebrain bundles, and the anterior commissure. In the anterior and medial diencephalon, TH-IR perikarya contacting the cerebrospinal fluid (CSF-C perikarya) were located in the preoptic recess organ (PRO), the organum vasculosum laminae terminalis and the suprachiasmatic nucleus. Numerous TH-IR perikarya, not contacting the CSF, were present in the posterior preoptic nucleus and the ventral thalamus. At this level, DA-IR CSF-C neurons were only located in the PRO. In the posterior diencephalon, large populations of 5-HT-IR and DA-IR CSF-C perikarya were found in the paraventricular organ (PVO) and the nucleus infundibularis dorsalis (NID); the dorsal part of the NID additionally presented TH-IR CSF-C perikarya. Most regions of the diencephalon showed an intense monoaminergic innervation. In addition, numerous TH-IR, DA-IR and 5-HT-IR fibers, orginating from the anterior and posterior hypothalamic nuclei, extended ventrally and reached the median eminence and the pars intermedia of the pituitary gland. In the midbrain, TH-IR perikarya were located dorsally in the pretectal area. Ventrally, a large group of TH-IR cell bodies and some weakly stained DA-IR and 5-HT-IR neurons were observed in the posterior tuberculum. No dopaminergic system equivalent to the substantia nigra was revealed. The possible significance of the differences in the distribution of TH-IR and DA-IR neurons is discussed, with special reference to the CSF-C neurons.Abbreviations
AM
amygdala
-
CAnt
commissura anterior
-
CH
commissura hippocampi
-
CP
commissura posterior
-
Ctm
commissura tecti mesencephali
-
DH
dorsal hypothalamus
-
DTh
dorsal thalamus
-
FLM
fasciculus longitudinalis medialis
-
Fsol
fasciculus solitarius
-
H
habenula
-
LFB
lateral forebrain bundle
-
ME
median eminence
-
MFB
medial forebrain bundle
-
NID
nucleus infundibularis dorsalis
-
nIP
neuropil of nucleus interpeduncularis
-
NPOP
nucleus preopticus posterior
-
NS
nucleus septi
-
OVLT
organum vasculosum laminae terminalis
-
PD
pars distalis
-
Pdo
dorsal pallium
-
PHi
primordium hippocampi
-
PI
pars intermedia
-
Pl
lateral pallium
-
PN
pars nervosa
-
PRO
preoptic recess organ
-
Ptec
pretectal area
-
PVO
paraventricular organ
-
Ra
nucleus raphe
-
Rm
nucleus reticularis medius
-
SCO
subcommisural organ
-
ST
striatum; strm stria medullaris thalami
-
strt
stria terminalis thalami
-
TM
tegmentum mesencephali
-
TO
tectum opticum
-
TP
tuberculum posterius
-
trch
tractus cortico-habenularis
-
trmp
tractus mamillopeduncularis
-
VH
ventral hypothalamus
-
Vm
nucleus motorius nervi trigemini
-
VTh
ventral thalamus
-
II
optic nerve 相似文献
996.
Immunohistochemical localization of Na+-dependent glucose transporter in rat jejunum 总被引:2,自引:0,他引:2
Kuniaki Takata Toshiko Kasahara Michihiro Kasahara Osamu Ezaki Hiroshi Hirano 《Cell and tissue research》1992,267(1):3-9
Summary Glucose is actively absorbed via a Na+-dependent active glucose transporter (Na-GT) in the small intestine. We raised a polyclonal antibody against the peptide corresponding to amino acids 564–575 of rabbit intestinal Na-GT, and localized it immunohistochemically in the rat jejunum. By means of immunofluorescence staining, Na-GT was located at the brush border of the absorptive epithelial cells of the intestinal villi. Electron-microscopic examination showed that Na-GT was localized at the plasma membrane of the apical microvilli of these cells. Little Na-GT was found at the basolateral plasma membrane. Along the crypt-villus axis, all of the absorptive epithelial cells in the villus were positive for Na-GT. In addition to the brush border staining, the supranuclear positive staining, which was shown to be the Golgi apparatus by use of electron microscopy, was seen in cells located between the base to the middle of the villus. Cells in crypts exhibited little or no staining for Na-GT. Goblet cells scattered in the intestinal epithelium were negative for Na-GT staining. These observations show that Na-GT is specific to the apical plasma membrane of the absorptive epithelial cells, and that the onset of Na-GT synthesis may occur near the crypt-villus junction. 相似文献
997.
Tatsumi Kusakabe 《Cell and tissue research》1992,269(1):79-85
Summary The ontogeny of substance P, CGRP (calcitonin gene-related peptide), and VIP (vasoactive intestinal polypeptide) containing nerve fibers in the carotid labyrinth of the bullfrog, Rana catesbeiana, was examined by the peroxidase-antiperoxidase method. The time of appearance of these three peptides was different for each. First, CGRP fibers appeared in the wall of the carotid arch and external carotid arteries, and in a thin septum between these two arteries at an early stage of larval development (stage III). At stage V, substance P immunoreactive fibers appeared, and VIP fibers were detected at the early metamorphic stage (stage XXII). Up to the completion of metamorphosis, the number of these fibers remained low. From 1 to 5 weeks after metamorphosis, substance P, CGRP, and VIP fibers increased in number to varying degrees. By 8 weeks after metamorphosis, the distribution and abundance of these fibers closely resembled those of the adults. Some CGRP and VIP immunoreactive glomus cells were found at the stages immediately before and after the completion of metamorphosis. These findings suggest that substance P, CGRP, and VIP fibers during larval development and metamorphosis may be nonfunctional, and start to participate in vascular regulation only after metamorphosis. The transient CGRP and VIP in some glomus cells may be important for the development of the labyrinth, or may take part in vascular regulation through the close apposition of the glomus and smooth muscle cells (g-s connection). 相似文献
998.
Structural interactions of actin filaments and endoplasmic reticulum in honeybee photoreceptor cells
Otto Baumann 《Cell and tissue research》1992,268(1):71-79
Summary Fluorescent phallotoxins and heavy meromyosin were used to reveal the organization of the actin cytoskeleton in honeybee photoreceptor cells, and the relationship of actin filaments to the submicrovillar, palisade-like cisternae of the endoplasmic reticulum (ER). Bundles of unipolar actin filaments (pointed end towards the cell center) protrude from the microvillar bases and extend through cytoplasmic bridges that traverse the submicrovillar ER. Within the cytoplasmic bridges, the filaments are regularly spaced and tightly apposed to the ER membrane. In addition, actin filaments are deployed close to the microvillar bases to form a loose web. Actin filaments are scarce in cell areas remote from the rhabdom; these areas contain microtubule-associated ER domains. The results suggest that the actin system of the submicrovillar cytoplasm shapes the submicrovillar ER cisternae, and that the distinct ER domains interact with different cytoskeletal elements. 相似文献
999.
Summary Aberrations of photoreceptor ultrastructure resulting from carotenoid/retinoid (vitamin A) deprivation were studied in the retina of Manduca sexta. The syndrome of chromophore deficiency included hypertrophy of smooth endoplasmic reticulum, variable dilation of rhabdomeric microvilli, the insertion of endomembrane fingers into such enlarged microvilli, and the formation of rhabdomeric vacuoles, intracellular compartments containing microvilli similar to those of the rhabdomere. Retinas were processed either with conventional procedures employing preliminary aldehyde fixation followed by heavy metal postfixation, or by fixation and incubation in unbuffered OsO4. The latter method deposits osmium throughout the endomembrane system, within the rhabdomeric vacuoles, and in the extracellular space of the rhabdom. However, the intravillous fingers were rarely impregnated with osmium, despite their continuity with densely stained cisternae of the smooth endoplasmic reticulum. We suggest that the insertion of endomembrane fingers into dilated microvilli results from a cytoskeleton-mediated link between cisternae of the smooth endoplasmic reticulum and the rhabdomeric membrane, an association that may be important in the turnover of photoreceptor membrane. We interpret endomembrane hypertrophy and development of rhabdomeric vacuoles as symptoms of disturbance in the pathway leading to the assembly of the rhabdomere resulting from reduced synthesis of visual pigment. 相似文献
1000.
Summary Leu-enkephalin containing secretory granules were demonstrated in axon terminals of immunogoldlabeled electron-microscopic sections of the sinus gland of three brachyuran crustaceans. These granules have a diameter of 120+-15 nm and differ in electron density from those located in adjacent terminals containing hyperglycemic or molt-inhibiting hormone. These neurohormones do not show co-localization with leu-enkephalin. The cross-reactivity of leu-enkephalin antiserum with met-enkephalin is less than 1%. The sinus glands of the three species examined show no immunoreactivity for FMRF-amide. A modulatory activity of endogenous enkephalin by paracrine mechanisms is suggested. 相似文献