摘要:

AbstractBlood supply and drainage of the outer medulla of the rat kidney were studied by scanning electron microscopy of vascular casts, using both arterial (n = 10) and venous (n = 10) injections of resin. Both outer and inner stripes of the outer medulla were supplied through different arterial capillary networks arising from efferent arterioles and arterial (descending) vasa recta. In contrast to previous studies using silicone rubber and light microscopy, a rich arterial capillary network supplying the outer stripe was demonstrated. Capillaries in the outer stripe and outer part of the inner stripe drained into venous vasa recta between vascular the bundles, while capillaries in the inner part of the inner stripe drained into venous vasa recta within the bundles. The results indicate that each zone in the outer medulla is supplied through separate capillary networks. The demonstration of a rich capillary network in the outer stripe of the outer medulla suggests that the predilection of this zone for tubular necrosis with ischemic or toxic injury is not related to a sparse capillary blood supply.

ISSN:0003-276X    

DOI:10.1002/ar.1092100202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractThe structure and enzymatic content of rat and hamster preovulatory follicles were examined using morphologic, qualitative, and quantitative cytochemical techniques. Interfollicular structure in both types was similar but lipid droplet distribution differed. The rat theca contained many more droplets than the hamster, while the hamster membrana granulosa contained more droplets than the rat. δ5‐3β‐hydroxysteroid dehydrogenase (3βOHD) activity and glucose‐6‐phosphate dehydrogenase (G‐6‐PD) Types IH and IIH generation were measured using quantitative cytochemistry. Rat theca and granulosa contained more 3βOHD activity than found in comparable regions in hamster. G‐6‐PD Type IH and Type IIH generation were the same in comparable regions of rat and hamster, but in rat there was more Type IIH than IH, while the converse existed in hamster. These differences and their relationship to follicular steroid produ

ISSN:0003-276X    

DOI:10.1002/ar.1092100203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractThree types of nonciliated secretory epithelial cells contribute material to the mucous lining of pulmonary airways: mucous cells, serous cells, and Clara cells. Extensive interspecies variation exists, especially between humans and laboratory mammals, with regard to occurrence, distribution, and granule content of these secretory cells. This study was designed to characterize one aspect of these differences in one species of nonhuman primate, the rhesus monkey. The complex carbohydrates of secretory granules present in the tracheal epithelium were characterized cytochemically. The tracheas of seven monkeys were fixed by airway infusion, processed, and embedded for both light and transmission electron microscopy. Histochemical stains including Alcian blue‐periodic acid Schiff, dialyzed iron, and high iron diamine‐Alcian blue were applied to serial methacrylate sections. The mucous cells were the predominant secretory cell type of the trachea and contained periodate‐reactive sulfated glycoconjugates. The mucous secretory granules, as resolved with the electron microscope, consisted of a mesh or matrix surrounding a biphasic core. The matrix was stained by all cytochemical reactions used, which included periodic acid‐thiocarbohydrazide‐silver proteinate, dialyzed iron, low iron diamine, and high iron diamine. The biphasic core also reacted with the four stains, but most intensely with high iron diamine. We conclude from this study that (1) the mucous secretory granule contains carbohydrate throughout all phases of the granule, (2) the mucous granule contains periodate‐reactive sulfated glycoconjugates, with sulfate esters concentrated in the core of the granule, and (3) the mucous granules of rhesus trachea morphologically and cytochemically resemble those described in hu

ISSN:0003-276X    

DOI:10.1002/ar.1092100204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractMorphology and postnatal development of the porcine lung are described in animals ranging in age from newborn through 60 days. Standardized fixation was accomplished by intratracheal instillation of glutaraldehyde under constant pressure. Light microscopic, scanning, and transmission electron microscopic investigations revealed that the porcine lung follows the common architecture of mammalian lungs, but has certain peculiarities as well: intravascular macrophages, ultrastructurally similar to Kupffer cells, are attached to endothelial cells in pulmonary capillaries and are involved in erythrophagocytosis during the first postnatal weeks. Type II pneumocytes of newborn pigs exhibit signs of cell activation, mainly complex nuclear bodies in the cell nuclei. At the same time high levels of 17‐hydroxycorticosteroids are observed in the newborn blood plasma. Terminal airways of the porcine lung are nonalveloarized and are, therefore, of purely conductive function.At birth the porcine lung exhibits a high degree of maturity, and thickwalled primary saccules, as described in newborn rodents, are not seen. Septa appear straight and smooth, owing to rare ramification. Septal buds are discernible, and two capillary networks visible on both sides of septal cross sections are seen. Further subdivision of the airspaces occurs in the first two postnatal weeks. Precociousness and fast postnatal growth of the porcine species are assumed to be the reason of this advanced degree of lung maturity at birth and the following rapid pulmonary developmen

ISSN:0003-276X    

DOI:10.1002/ar.1092100205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractThe ultrastructure of mitochondria in perioportal and perihepatic hepatocytes from newborn, 5‐, 10‐, and 20‐day‐old, and adult male ddY mice was analyzed by quantitative electron microscopy. In newborn and 5‐ and 10‐day‐old animals, the axial ratio (length per diameter), surface to volume ratio (area of the outer membrane per unit mitochondrial volume), and volume density were not significantly different between periportal and periphepatic cells. In 20‐day‐old and adult animals, the surface to volume ratio was greater in perihepatic cells than periportal cells, and the volume density was greater in periportal cells than perihepatic cells. The axial ratio became greater in perihepatic cells than periportal cells in adult animals. However, there were no differences in the surface density of the outer membrane, and of the inner membrane and cristae between the cells of both zones in all age groups examined. When the data were expressed as volume and area per cell, the patterns of subacinar distribution and age‐related changes differed from the patterns seen in the volume and surface density data mainly in adult animals. This difference was generally caused by the marked increase in hepatocyte volume between 20 days of age and adulthood, especially in perihepatic cells.The results show that differences between mitochondria in periportal cells and those in perihepatic cells in the shape (the axial and surface to volume ratios), volume density, and area of the outer membrane per cell, evident in adult animals, are not present in newborn animals but arise during po

ISSN:0003-276X    

DOI:10.1002/ar.1092100206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractThe purpose of this study was to subject groups of weanling male rats each to a specific 10% simulated increase in body weight, ranging from 1.1G–2.0G, using constant centrifugation. (In this paper, “G” is the acceleration due to gravity.) After 30 and 60 days, rats were killed and perfused with 10% buffered neutral formalin (B.N.F.). The humerus, radius, ulna, femur, and tibia were removed, cleared of all soft tissues, weighed, and the total length measured. Bone robusticity was calculated using the ponderal index: bone length/\documentclass{article}\pagestyle{empty}\begin{document}$ \sqrt[3]{{{\rm bone}\,{\rm weight}}} $\end{document}. Tukey's Multiple Range Test was used. The data suggest that the specific limb bone, G, and duration of centrifugation are each factors in the response of limb bones to simulated increases in body w

ISSN:0003-276X    

DOI:10.1002/ar.1092100207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractThe purpose of this investigation was to subject separate male and female groups of weanling hypophysectomized rats each to a specific 10% simulated increase in body weight using constant centrifugation, ranging from 1.1G to 2.0G, to study changes in bone robusticity and bone mineral content. (In this paper, “G” is the acceleration due to gravity.) After 60 days of centrifugation at 24 rpm, the rats were killed and the humerus, radius, ulna, femur, and tibia were removed, cleared of soft tissues, weighed, measured, decalcified with EDTA, and reweighed. Bone robusticity was determined using the ponderal index: P.I. = bone length ÷\documentclass{article}\pagestyle{empty}\begin{document}$ \sqrt[3]{{{\rm bone}\,{\rm weight}}} $\end{document}; and bone mineral content (BMC) was determined using the formula: BMC = [(Wu– Wd) ÷ Wu] × 100. Tukey's Studentized Multiple Range T Test was used. The data suggest that, for both male and female hypophysectomized rats, bone robusticity is decreased with simulated increases in body weight; also, for males, a bimodal curve describing the relationship between BMC and simulated increases in body weight is s

ISSN:0003-276X    

DOI:10.1002/ar.1092100208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractGroups of newborn rats were each subjected to a specific 10% simulated increase in body weight, ranging from 1.1G to 2.0G, to study changes in bone robusticity. (In this paper, “G” is the acceleration due to gravity.) Constant centrifugation was used. At 90 days of age, the rats were killed and the humerus, radius, ulna, femur, and tibia were removed, weighed, and measured. Bone robusticity was calculated using the ponderal index: bone length/\documentclass{article}\pagestyle{empty}\begin{document}$ \sqrt[3]{{{\rm bone}\,{\rm weight}}} $\end{document}. Tukey's Multiple Range Test was used. The data suggest that, for both males and females, bone robusticity is increased with simulated increases in body wei

ISSN:0003-276X    

DOI:10.1002/ar.1092100209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractThe qualitative and quantitative structural development of the feline mental nerve (MN), a branch of the inferior alveolar nerve (IAN), was studied by electron microscopy from 40 days postconception (dpc) (about 2 weeks before birth) to 11 years after birth. Myelination was initiated at 40–45 dpc. At 2 months after birth de novo myelination was completed, and the larger myelinated axons had achieved a fully differentiated nodal‐paranodal morphology. Size growth of myelinated axons continued until 6 months, when a bimodal size distribution between 1 and 12 months was established. When compared to the IAN, the MN contained a higher proportion of unmyelinated axons. Age‐related signs of axon degeneration, which previously were recorded in the IAN, were lacking in the MN. This suggests that senescent IAN axon degeneration is related to dental rather than to cutaneous MN bra

ISSN:0003-276X    

DOI:10.1002/ar.1092100210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractRapid occlusion of the middle cerebral artery (MCA) in the 36‐day‐old normal Wistar rat results in change of the dorsal collaterals joining branches of the anterior and middle cerebral arteries. As compared to similarly positioned vessels on the opposite hemisphere and arterioles in unoperated rats of 56 days, of age, there were significantly (P0.05) between occluded and unoperated rats. There was no evidence that new vessels were added during the 20‐day ligation period. The mean collateral tortuosity value was significantly (P<0.01) greater for large diameter vessels on the right occluded side as compared to vessels on the left hemisphere or vessels in unoperated age‐matched control rats. The greater tortuosity values of vessels on the occluded side were evidence that collateral vessel length was increased by 24–29% after MCA occlusion. Speculation was made about possible mechanisms responsible for these v

ISSN:0003-276X    

DOI:10.1002/ar.1092100211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY