摘要:

AbstractThis developmental study of the dorsal cochlear nucleus (DCN) was based upon electron microscopic and Golgi preparations from many postnatal kittens (newborn‐4 months) and adult cats. Seven developmental stages were defined according to time of first alterations in size of layers, size, shape and packing of fusiform neurons; cytology of cytoplasmic organelles; cytology of fusiform cell layer (FCL) neuropil; and time when each of eight types of synaptic endings (defined in adults) appeared. During stage 1 (newborn‐2.5 days), fusiform and small cells were tightly packed. Fusiform cells, covered with multiform projections, were filled with large Golgi complexes and Nissl bodies. Free ribosomes were packed within invaginations of the nuclear envelope. The FCL expanded during stage 2 (3–6 days), both by growth of fusiform cells and by elaboration of FCL neuropil. Type 1 and type 5 endings appeared. During stage 3 (7–14 days), adult synaptic types 2, 2a, 3 and 4, plus a newly defined type 3a ending were found. Somatic projections decreased in number and length. This decrease continued into stage 4 (15–25 days), when synaptic type 1a appeared. Fusiform cells were separated by further growth of FCL neuropil during stage 5 (26–44 days). Adult synaptic type 5a was first noted during stage 6 (45–95 days), when glomeruli and synaptic nests were also identified. In the final stage 7 (120 days and older), glomeruli and nests matured, while maximally sized fusiform cells had smooth somatic membranes and nuclear envelopes. All adult synaptic types were mature after 120 postnatal days. This long interval for staged DCN development facilitates correlated developmental, electrophysiological studies. The latter might clarify functions of known inputs to DCN by matching maturation times of those inputs with appearance of specific physiologic

ISSN:0002-9106    

DOI:10.1002/aja.1001530302

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

年代:1978

数据来源: WILEY

摘要:

AbstractMany of the cilia in the oviducts of rhesus monkeys are formed in the follicular phase of the menstrual cycle, and lost in the subsequent luteal phase (Brenner, 1969a). This striking phenomenon has rarely been observed in other species, and its occurrence in human oviducts is a point of dispute. This study was designed to determine whether cyclic shedding and renewal of oviductal cilia occur in a primate species other than the rhesus monkey and to reveal the surface characteristics of the oviductal mucosa in a subhuman primate. Oviducts were removed fromMacaca nemestrinafemales at three specific times during the menstrual cycle and examined by scanning electron microscopy. The fimbriae appeared to be extensively ciliated at midcycle but only sparsely ciliated in the early follicular and late luteal phases. Early in the cycle, large numbers of cells were seen in the process of ciliogenesis, but in the late luteal phase there were signs of ciliary degeneration and shedding. The ampullar epithelium showed similar though less dramatic changes, and the isthmus little change. Long‐term ovariectomy caused almost complete deciliation of the fimbrial and ampullar epithelium, but treatment of ovariectomized animals with estrogen for only a few days restored the epithelium to normal. Despite the high degree of variability in the mucosa, it was clear that the oviducts ofM. nemestrina, like those of the rhesus monkey, undergo cyclic ciliogenesis and deciliation. The surface features of the oviductal lining inM. nemestrinaare described here for the first tim

ISSN:0002-9106    

DOI:10.1002/aja.1001530303

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

年代:1978

数据来源: WILEY

摘要:

AbstractSublingual and submandibular glands were prepared for light and electron microscopy, and for histochemical staining with periodic acid‐Schiff (PAS), Alcian Blue (AB) or both (AB‐PAS). Between 15 and 17 days post‐conception, the sublingual gland undergoes active morphogenesis from a single, solid bud into a branched glandular tree. At 18 days the first overt signs of secretory differentiation appear in the formation of cells with three kinds of secretion granules; that is, electron‐dense serous granules, empty‐looking mucous granules with fine thread‐like substructures, and granules which have the general appearance of mucous granules but also contain an internal, electron‐dense core (“mixed” granules). During the period from 18 to 20 days, all three types of granulated cells increase in number, with mucous cells predominating, and they all border directly on the acinar lumina, in seemingly random combinations in different acini. This diversity is reflected in the histochemical staining, since most acini and cells are both PAS‐ and AB‐positive, but a substantial minority stain only with PAS, indicating that they contain serous granules. By comparison, all secretory cells in the submandibular gland stain with PAS but not with AB after the initial appearance of secretory granules at 18 days. From 20 days to birth (at 22 days), the cells with mixed granules disappear, while the cells with serous granules become fewer in number and displaced to the peripheral outpocketings of the acini. As a result of these changes, the general organization in the newborn is similar to that in the adult, i.e., purely mucous acini

ISSN:0002-9106    

DOI:10.1002/aja.1001530304

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

年代:1978

数据来源: WILEY

摘要:

AbstractThe efferent projections of the parvocellular vasopressin‐ and neurophysin‐containing neurons of the suprachiasmatic nucleus (SCN) have been investigated in the mouse, rat and guinea pig, using specific antisera to vasopressin and neurophysin in the unlabelled antibody‐enzyme immunoperoxidase method. In all three species, parvocellular perikarya containing vasopressin and neurophysin were found in the SCN, primarily in the medial, dorsal and rostral part of the nucleus. The fine‐caliber vasopressin‐ and neurophysin‐containing fibers arising from SCN neurons can easily be distinguished from the large‐caliber vasopressin and neurophysin fibers of magnocellular neurons which pass from the supraoptic and paraventricular nuclei primarily to the neural lobe of the pituitary, but also to extrahypothalamic sites. Fine‐caliber fibers leave the SCN in various directions to form several pathways. The major projections run (1) rostrodorsally to the lateral septum, and (2) dorsally to the medial dorsal thalamus and lateral habenula. Smaller projections course rostrally to the nucleus of the diagonal tract (of Broca), and dorsocaudally to the posterior hypothalamus and interpeduncular nucleus. In addition, many fibers of the dorsal thalamic projection continue beyond the lateral habenulae through the central grey of the mesencephalon to the area of the nucleus of the solitary tract. In all target areas, fibers were observed only in distinct portions of the nuclei and were not distributed to the whole nucleus. None of the fine‐caliber fibers from SCN neurons project to, or even towards, the median eminence and neural lobe. No oxytocin‐positive SCN neurons or fine‐caliber fibers could be found. In Brattleboro rats, with hereditary vasopressin deficiency, no vasopressin‐ or neurophysin‐positive SCN neurons or fine‐caliber fibers could be found. In contrast to vasopressin and neurophysin fibers from magnocellular neurons of the supraoptic and paraventricular nuclei, fine‐caliber vasopressin and neurophysin fibers from SCN neurons do not terminate at capillaries. A large number of these fibers make axo‐somatic contacts with neurons in the projection areas. It is concluded that vasopressin and neurophysin from parvocellular SCN neurons are not released into the bloodstream, but may affect neurons in

ISSN:0002-9106    

DOI:10.1002/aja.1001530305

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

年代:1978

数据来源: WILEY

摘要:

AbstractPrevious work on dog knee menisci demonstrated structural differences between the meniscal horns and the meniscal bodies (O'Connor, 1976). Of particular interest was the observation that the meniscal horns possessed an abundant blood and nerve supply, while the meniscal bodies did not. The presence of nerves in the meniscal horns prompted the speculation that menisci might perform a sensory function.The present study was undertaken in order to establish whether or not similar regional differences existed in cat knee menisci, structures previously believed to lack a corpuscular mechanoreceptor system (Freeman and Wyke, 1967).Differences between the meniscal horns and meniscal bodies similar to those reported in the dog were found to characterize cat knee menisci. In particular, the meniscal horns possessed a rich neurovascular supply, while the meniscal bodies did not. Most important, at least two morphologically different mechanoreceptors were identified in the meniscal horns, but none were identified in the meniscal bodies.

ISSN:0002-9106    

DOI:10.1002/aja.1001530306

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

年代:1978

数据来源: WILEY

摘要:

AbstractThe localization of renin in the developing mouse submandibular gland was studied immunocytochemically using the unlabelled antibody‐enzyme method of Sternberger (1974). Bouin‐fixed submandibular glands of mice of both sexes were examined at 5‐day‐intervals from birth (day 0) to 50 days of age. At all stages studied, only granular convoluted tubule (GCT) cells stained immunocytochemically for renin; such cells were first seen in glands of 30‐day‐old males and of 30‐day‐old females. The size and number of renin‐containing GCT cells increased rapidly in males, attaining adult status by 50 days of age. In females, differentiation of GCT cells immunoreactive for renin was slower and less regular than in males, and at 50 days of age the GCT segment had not yet reached adult conditions with respect to the distribution of renin. Renin appears in GCT cells at later ages than other GCT cell products (e.g., EGF and amylase), suggesting the existence of independent developmental control for the expression of various biologically active subst

ISSN:0002-9106    

DOI:10.1002/aja.1001530307

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

年代:1978

数据来源: WILEY

摘要:

AbstractAntibody against the intermediate‐sized filaments from gizzard smooth muscle was used to determine the presence or absence of reacting 10‐nm filaments in different cell types. The antibody against gizzard 10‐nm filaments reacted with filaments in cultured smooth muscle cells, skeletal myotubes and postmitotic skeletal myoblasts. It did not bind to the 10‐nm filaments present in replicating presumptive myoblasts and fibroblasts, or the 10‐nm filaments in spinal gangl

ISSN:0002-9106    

DOI:10.1002/aja.1001530308

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

年代:1978

数据来源: WILEY

摘要:

AbstractAn immunohistochemical procedure was used to detect cells which appear to bind insulin in the mouse brain. Strong fluorescence was observed in the cell bodies and processes of tanycytes lining the third ventricle and in the choroid plexi. These findings suggest that insulin enters the central nervous system, and indicate a route for its possible transport. This adds credence to earlier observations that the hypothalamic ependymal cells and processes form a highly organized and functional system, with different cells selectively absorbing (or sensing) particular substances from the systemic and ventricular circulations and transporting them (or information about them) to specific neuron receptors in the hypothalamus.

ISSN:0002-9106    

DOI:10.1002/aja.1001530309

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

年代:1978

数据来源: WILEY

摘要:

AbstractThe Gomori aldehyde‐fuchsin (AF) method for selective staining of neurosecretory substance (NSS) has been adapted to tissue previously prepared for both scanning and transmission electron microscopy (SEM/TEM). The procedure results in precise correlation of light microscopic (LM) histochemistry with SEM/TEM of the same tissu

ISSN:0002-9106    

DOI:10.1002/aja.1001530310

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

年代:1978

数据来源: WILEY

摘要:

AbstractThe object of this study was to determine the type of cerebral vessel affected by injection of radiopaque contrast agents used in cerebral angiography. Seventeen rabbits were prepared surgically for a left intracarotid injection of methylglucamine iothalamate (Conray 60) or methylglucamine diatrizoate (Reno‐M‐60). Extravasations of the tracers, Evans blue and horseradish peroxidase, occurred in the left half of the brain and occasionally in the right half. Within those areas of blood‐brain barrier breakdown, the frequency of leakage was 60% for arterioles, 25% for venules, and 12% for capillaries. The leakage appeared to be primarily intercellular, rather than intracellular. This study provides evidence that greater blood‐brain barrier alterations occur in arterioles and venules than in capillaries following cerebral angi

ISSN:0002-9106    

DOI:10.1002/aja.1001530311

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

年代:1978

数据来源: WILEY