摘要:

Fiber type differentiation as revealed by myosin ATPase activities and the immunological analysis of myosin light chains (MLC) by the Western blotting method were done on the postnatal rat soleus and extensor digitorum longus (EDL) muscles. In the soleus, type 1 (slow-twitch) muscle fibers gradually increase in percentage after postnatal day 10, and, in the EDL, the differentiation of type 2A and 2B (fast-twitch) muscle fibers is also pronounced between postnatal days 10 and 15. The present immunological analysis of MLC indicates that the antigenicity of LclS becomes more intense with a rapid decrease in anti-genicity of Lc2F from postnatal day 7 in the soleus, while the antigenicity of LclF becomes noticeable during the same period in the EDL. These results suggest that the differentiation of slow-twitch fibers is mainly due to that of Lc1S in the soleus and the differentiation of fast-twitch fibers is mainly due to that of Lc1F in the EDL

ISSN:1422-6405    

DOI:10.1159/000147221

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

We studied the morphological changes in rat Harderian glands 30 min after injection of cholinergic secretagogues. In controls, the glands exhibited a tubuloalveolar structure with relatively wide lumina, in which some osmiophilic dense droplets exocytosed from glandular cells were observed. Also two types of glandular cells (type A cells and type B cells sometimes showing exocytotic figures of lipid-secretory vacuoles) and myoepithelial cells were recognized. After injection of carbamylcholine chloride (subcutaneously, 0.1 mg/kg body weight), which has both nicotinic and muscarinic actions, many of the alveolar lumina dilated and contained a small number of osmiophilic droplets. Exocytotic figures in both types of cells and a pronounced decrease in the number of vacuoles in the glandular cells were observed. However, there was no evidence of apocrine or holocrine secretion. The injection of the higher dose of carbamylcholine (1.0 mg/kg) caused fusion of secretory vacuoles in the apical cytoplasm and contraction of myoepithelial cells. Most alveoli showed no clear lumina; their centers were jammed with cytoplasmic fragments and accumulated secretory products. Massive discharge of cytoplasmic fragments containing some secretory vacuoles was often observed. This may be classified as apocrine secretion. Bethanechol chloride (subcutaneous injection, 1.0 mg/kg), a muscarinic agonist, stimulated the Harderian-gland secretion, and enhanced exocytosis was observed. The discharge from the glandular cells, following injection of various doses of carbamylcholine, were almost inhibited by atropine sulfate, a muscarinic antagonist. The present results suggested that the cholinergic systems regulate the secretion of rat Harderian-gland cells which have muscarinic receptors.

ISSN:1422-6405    

DOI:10.1159/000147222

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Immunocytochemical studies on the adult human brain have shown that transferrin is localized within three main compartments in the adult human brain. Oligodendrocytes and some astrocytes together with cells of the choroid plexus showed the highest intensity of staining. Neuronal staining occurred mainly within pyramidal or large polygonal cells, but this showed considerable regional variation being most marked in areas such as the cerebral cortex, amygdala, hippocampus, brainstem and cerebellar Purkinje cells. Small neurones such as caudate interneurones and granule cells showed relatively low activity. Diffuse immunostaining of the neuropil was evident, particularly where heavy neuronal or glial staining occurred. Immunostaining was also observed in white-matter fibre tracts. This pattern of distribution helps to provide a model for the mechanisms responsible for iron homeostasis in the normal brain.

ISSN:1422-6405    

DOI:10.1159/000147223

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The development of the rabbit pineal gland has been studied by light and electron microscopy from the 1st to the 120th postnatal day. After 24 h of postnatal life, the pineal parenchyma is highly cellular, showing two identifiable cell types: pinealocytes I and II. Immature type II pinealocytes arrange either in cellular cords or clusters or forme rosette-like structures. At the 5th postnatal day, corticomedullar differentiation is established. Rosette-like structures and cellular cords are absent from the cortex. Along the postnatal period, nuclei of pinealocytes are set apart due to cytoplasmic widening and development of cell processes. These structures pervade the cellular cords and rosette-like structures formed by immature type II pinealocytes. Rosette-like structures are no longer seen beyond the 30th postnatal day, and cords of type II pinealocytes from the 90th postnatal day on. At this time, the rabbit pineal gland is considered to be histologically mature.

ISSN:1422-6405    

DOI:10.1159/000147224

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The glycoconjugates of the lateral prostate were examined ultrastructurally by lectin-gold histochemistry in combination with a low-temperature embedding technique using Lowicryl K4M. The binding patterns of concanavalin A, wheat germ agglutinin, Griffonia simplicifolia, soybean agglutinin, peanut agglutinin, Ricinus communis agglutinin isolectin I, Griffonia simplicifolia isolectin B4, Ulex europaeus isolectin I and Phaseolus vulgaris agglutinin P have been documented in the subcellular compartments of the lateral prostate. The results show that the granular endoplasmic reticulum (GER) is rich in glycoproteins with mannosyl residues while the Golgi cisternae, secretory granules and microvilli are less so. The mannose (Man) and N-acetylgucosamine (GlcNAc) residues present in the GER of the epithelial cells may be associated with the initial assembly of the N-linked oligosaccharides of glycoproteins. The secretory granules exhibited different reactivities to lectins. Most of the lectin-binding sites confined to the limiting membranes may play a role in the transport of plasmalemma glycoconjugates to the apical plasma membrane. The epithelial Golgi stack is rich in GlcNAc, galactose (Gal), N-acetylgalactosamine (GalNAc) and sialic acid residues, and a compartmental organization of the Golgi stack is apparent which might be associated with the sequential addition of sugar residues to the oligosaccharides. The plasma membrane contains abundant Man, GlcNAc, Gal, GalNAc and complex carbohydrates, especially in the micro villi, and a differential lectin labelling was noted between the apical and basolateral plasma membrane. The present study showed that fucose-containing glycoconjugates were detected in the apical plasma membrane of the lateral prostate. The stromal extracellular matrices as well as the epithelial basement membranes demonstrated weak lectin reaction. Man, GlcNAc, Gal residues and complex sugars were also noted in the stromal tissues of the lateral prostate including the extracellular matrix, capillaries and smooth muscle.

ISSN:1422-6405    

DOI:10.1159/000147225

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The organization of the arterial vessels of dog lymph nodes (LN) was studied using methods of visualization of the vasculature by systemic injection of different tracers (colloidal carbon, Micropaque® resin and methylmethacrylate) followed by observation of the samples by light microscopy (after clearing of the thick sections of LN) or scanning electron microscopy (corrosion casts). LN from all of the three groups of nodes studied (tracheobronchial, paratracheal and popliteal) showed an extensive network of arterial vessels encircling the capsule of the organ. We found that branches of these capsular arteries penetrated deeply into the cortical domain of LN. The capsule-originating vessels appeared to have a significant participation in the blood supply of the LN parenchyma at the cortical domains of the organs. Our findings are in contrast with current views on the angiology of the LN that consider that virtually all of the arterial capillaries of the LN parenchyma come from hilar arteries. We propose, therefore, that important segments of the LN cortex receive their blood supply from capsular arteries rather than from hilar vessels

ISSN:1422-6405    

DOI:10.1159/000147226

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Calcitonin-gene-related-peptide (CGRP)-like immunoreactivity was localized in nerve fibres, neuronal somata and in mucosal endocrine cells of the human small intestine. Immunoreactive enteric neurons were more numerous in the submucous plexuses than in the myenteric plexus. Morphologically, they predominantly had the appearance of type II neurons. The majority of the CGRP-like immunoreactive nerve fibres ran within the ganglionic nerve plexuses. Only a small proportion could be observed in the lamina propria, the lamina muscularis mucosae, or the circular and longitudinal outer smooth muscle layer. These findings suggest that within the wall of the human small intestine neuronal CGRP of either extrinsic or intrinsic origin exerts its effect chiefly on other enteric neurons, and might be indirectly involved in the regulatory functions of the human small intestine.

ISSN:1422-6405    

DOI:10.1159/000147227

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The three-dimensional image of the microvascularization of the rat superior cervical ganglion (SCG) was examined using the vascular corrosion cast technique in conjunction with scanning electron microscopy. It was found that the rat SCG was a highly vascularized organ. Arteries supplying the ganglion gave rise to a subcapsular capillary plexus before branching off to become intraganglionic capillaries. Two types of intraganglionic capillaries, large and small, were observed throughout the organ. Numerous anastomoses among these capillaries were found before they converged into venules and collecting veins. However, a pattern of blood vessels resembling portal-like intraganglionic microcirculation could not be demonstrated.

ISSN:1422-6405    

DOI:10.1159/000147228

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The submandibular gland of the mouse was studied by high-resolution scanning electron microscopy, using the osmium-dimethylsulfoxide-osmium method. The three-dimensional structures of the intracellular membranous organelles of acinar cells were clearly revealed. The luminal surface of cisterns of the granular endoplasmic reticulum and Golgi apparatus exhibited particles of 8-15 nm in diameter. The secretory canaliculi presented short microvilli which were irregularly arranged. The striated duct cells were characterized by rich mitochondria arranged vertically in the basal portion. The lamellar mitochondrial cristae were noted in three-dimensional images. The luminal surface extended short microvilli, while that of the excretory duct cell presented complicated microplicae. The capillary endotheliocytes showed a few short microvilli, and their fenestrated areas were bordered by cytoplasmic crests. Fenestrae were 50-80 nm in diameter and showed a plug in their center. The basement membranes of the acini and capillaries showed a spongy structure with various strands and meshes. Collagenous fibrils crisscrossed on their surface.

ISSN:1422-6405    

DOI:10.1159/000147229

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The blood supply of the periosteum of the human tibia was investigated by anatomical dissection of 12 lower extremities which were filled with injection mass. By division of the tibia into 4 segments (proximal and distal fifths; proximal and distal diaphysis) a general supplying system of the periosteum was found. The proximal fifth of the tibial periosteum is nourished by branches of the arteriae recurrentes tibiales anterior et posterior and the aa. inferiores medialis et lateralis genus. At the proximal diaphysis (next three tenths of the tibia) periosteal branches arise from the aa. tibialis anterior and posterior, whereas the distal diaphysis is nourished exclusively by semicircular vessels of the a. tibialis anterior which twine around the bone and merge with each other at the facies medialis. Concerning the periosteal blood supply of the distal fifth of the tibia, two different types were found. In two thirds of the cases the lateral side was nourished by branches of the a. tibialis anterior, which are supported by vessels from the a. fibularis. In one third the latter branch was absent so that the rami periostales arising from the a. tibialis anterior nourished the lateral aspect of the distal tibia alone. The dorsal region was supplied in all cases by rami of the a. fibularis and a. tibialis posterior. On the medial side the periosteal nourishment is ensured only by anastomosis. Branches of the a. tibialis anterior supply the facies lateralis and facies posterior where it is supported by vessels of the a. tibialis posterior and in a minor region of rami of the a. fibularis (distal) and a. poplitea (proximal). Both the facies lateralis and facies posterior are nourished by direct branches which arise from the main arteries of the lower leg, whereas the facies medialis is supplied only by capillary anastomosis. The a. tibialis anterior is the artery of great importance concerning the arterial supply of the periosteum and the outer aspect of the cortex of the tibia. The autonomous region of this vessel is the periosteum of the distal diaphysis. It is known that this region has the highest incidence of congenital and acquired pseudarthrosis. Therefore an osteo- or corticotomy should be avoided in the distal diaphysis.

ISSN:1422-6405    

DOI:10.1159/000147230

出版商:S. Karger AG    

年代:1992

数据来源: Karger