Zeitschrift fur mikroskopisch-anatomische Forschung最新文献

The distribution of vasoactive intestinal polypeptide (VIP) containing nervous elements in the chicken pancreas was immunohistochemically investigated by light microscopy. Strongly VIP immunoreactive ganglia existed in the interlobular connective tissue. Ganglion containing both VIP immunoreactive and non-immunoreactive nerve cells was occasionally observed in the connective tissue. Almost all the ganglion cells also showed acetylcholinesterase (AChE) activity. No extrapancreatic nerve bundles containing VIP immunoreactive nerve fibres were detected. VIP immunoreactive nerve fibres formed plexuses in the subepithelial layer of secretory ducts and the muscle layer of small arteries. The distribution pattern of VIP immunoreactive nerve fibers was similar to that of AChE-positive nerve fibers on adjacent sections. The exocrine pancreas received a rich supply of varicose nerve fibers showing VIP immunoreactivity. B-islets also were richly innervated by VIP immunoreactive varicose nerve fibers, whereas A-islets, only poorly. These observations suggest that VIP containing nerves in the chicken pancreas have an intrinsic origin, are probably derived from VIP immunoreactive, intrapancreatic ganglion cells and innervate secretory ducts, arteries, acinar cells and B-islets, and that VIP must coexist with acetylcholine in the nervous elements.

The structure and ultrastructure of the following regions of the hypothalamo-hypophysial neurosecretory system (HHNS) in the population cycle of lemming were studied: supraoptic (SON), paraventricular (PVN) and arcuate nuclei (AN), the median eminence (ME) and posterior pituitary (PP). Being compared to the state of endocrine glands and gonads, and the level of reproduction stress in the population cycle of the lemming described earlier, the obtained data revealed a certain regularity. First, at the stages of decrease, increase and in the first period of the stage of population peak the activity of the SON-PP complex and AN is gradually increased. This coincides with intensified reproduction, intensified functioning of the thyroid gland and adrenal cortex. Second, while the population is decreasing, all the above functions become depressed, except that of the thyroid gland which, on the contrary, becomes active. In the second period of the stage of population peak, when reproduction stops abruptly, this regularity, however, does not hold, the activity of SON-PP complex and AN is sharply lowered, whereas that of PVN becomes very high. The structure of the thyroid damaged as a result of previous hyperfunction, is restored, and the adrenal cortex shows signs of hypercorticism. The present work is devoted to specificity of the HHNS functioning at the stage of population peak, referred to as crucial, and the pathways and mechanisms by which neurohormones produced by this system can affect the endocrine glands. In addition, the causes likely to lead to the mass death of animals at this stage, and biological significance of this fact are also given attention to.

A computerized morphometric analysis was performed on histological sections of the proximal and distal limbs of the chick embryo duodenum, from the 8th to the 15th day of incubation, with the aim of evaluating the quantitative aspects of organogenesis. A semiautomatic digital system was used. The areas of total section, of the lumen, of the wall and of its components (subserous stratum, muscle layer, lamina propria, epithelium) and the thickness of the epithelium and muscle layer were measured; the mean +/- S.E.M. of the values obtained was calculated. The percentage of shrinkage, due to the histological procedures, was calculated for each day. The values obtained were added to the measurements of each area and thickness thus giving the true value of each parameter measured. The differences between the mean values of the areas of the proximal and the distal tract were statistically evaluated. Exponential curves and r coefficient were determined to evaluate the general growing pattern of the mean area of the components of the duodenal wall, as a function of age. The main results are the following: the areas of the wall components of the proximal limb are always greater than the corresponding areas of the distal limb of the duodenum. There are some differences between the proximal and the distal limbs of the duodenum in the growing pattern of the intestinal wall components. The anlage of the duodenum also has a different developmental pattern compared with that of the chick embryo ileum.

Biocarbazin (DTIC synonym) is an anticancer drug acting as a purine analogue, as an alkylating agent, as a SH-group blocker. Biocarbazin administration in doses 50 and 200 mg/kg of body weight to adult male BALB/c mice suppresses the process of spermatogenesis. Seminiferous tubule of the testis displayed dose-dependent histological alterations manifested with decrease of mitotically dividing cells and increase in the number of multinucleated spermatocytes and spermatids. RNA synthetic activity studied by means of autoradiography showed a tendency for a reduction in the spermatogonia and pachytene spermatocytes.

The distribution of choline acetyltransferase- and gamma-aminobutyric acid-immunoreactivity as well as acetylcholinesterase-, gamma-aminobutyrci acid-transaminase- and monoaminooxidase-positive structures in the basal forebrain, hippocampal formation and neocortex of young adult and aged rats was compared. The changes in the staining and density of the immuno- and histochemical positive nerve cells and fibers observed provide evidence for the involvement of different transmitters in normal ageing.

The distribution of the membrane-bound magnesium ions-dependent adenosine triphosphatase (Mg-ATPase) activity has been studied ultracytochemically in rat meninges by the method of Wachstein and Meisel (1957). A device specially constructed to avoid preparation artefacts has been used to obtain sections from the parietal region of the head. The meninges display an intense though irregularly distributed ATPase activity marked by depositions of electron-dense reaction product (RP) which is almost absent in the outer and middle dural layers. In the borderline zone between dura mater and the arachnoid the RP deposits are found at the outer surface of the inner dural cells and at the contact sites between these cells and the dural neurothelium. The intercellular cleft(s) between the neurothelium and the outer arachnoidal layer, occupied by an "electron-dense band", remains free of RP. The strongest accumulations of reactions granules are observed on the surface of the leptomeningeal cells of the arachnoidal space. In the contact region between the inner arachnoidal and the outer pial layers the distribution of the RP is similar to the one observed in the interface zone dura mater/arachnoid, while the pial cells themselves are definitely reaction-positive. In all meningeal vessels RP is found at the lumenal and abluminal aspects of the endothelium as well as at the cell membranes of the perivascular cells. These results emphasize the importance of the dural neurothelium for the functions of the blood-cerebrospinal fluid (CSF)-barrier between the dural blood vessels and the CSF.

The morphodynamic response of the pineal gland in the period 5-30 min after a single ACTH injection was studied. In 5 min a saline injection, functioning as a control, elicited a prompt release of the pineal active compounds advocated to be contained in clear vesicles and structures traditionally labeled lipid droplets. In the subsequent time period, 15 min, a rise in the relative volume of the granular endoplasmic reticulum (GER) and the Golgi apparatus, as well as prosecretory granules, was interpreted as a sign of an increased pinealocyte activity which leads to the restoration of the pineal gland endocrine potential. A decline in the increased mass of this membranous elaborative compartment in 30 min could be understood as an illustration of the stabilisation of the pinealocyte stress-evoked response. The ACTH injection did not apparently change the pattern of the morphodynamic pinealocyte response promoted by the saline injection in 5 min. However, starting from 15 min, a significant increase of the mass of GER and the Golgi apparatus was found in both pinealocyte populations. The augmented presence of prosecretory granules and lipid droplets, in comparison with the saline-injected animals in the respective time period, as well as the absence of a clearly observable evidence of the pinealocyte secretory activity pointed out that the ACTH stimulative action on the pinealocyte membranous elaborative compartment rather facilitated the pinealocyte endocrine recovery than supported their current secretory activity. From the functional viewpoint, the results obtained suggest that a stress-induced ACTH burst could modulate the post-secretory restitution of the endocrine potential of previously stress-activated pinealocytes.

In the present study, a polyclonal antibody against pro-opiomelanocortin derivatives was characterized biochemically. Its immunoreactivity with structures of the arcuate nucleus and the median eminence was investigated by means of the immunogold method and compared with its reaction on adenohypophyseal cells with and without pre-adsorption with pro-opiomelanocortin derivatives. The antiserum detects ACTH and its fragments, in particular alpha-MSH, and beta-endorphin. In the adenohypophysis gold particles are exclusively located on small secretory granules situated in the periphery of branched cells. In the perikarya of the arcuate nucleus gold particles are observed on terminal vesicles abutting from the cis-face of the Golgi apparatus, on granules in its direct vicinity and on small dense core vesicles preferentially located in the cell periphery. Immunoreactive gold-labeled fiber profiles are found in a sub- or intra-ependymal position as well as in the nuclear neuropil proper. Here axodendritic and axosomatic synapses are observed. In both situations the gold particles are mostly restricted to the small dense core vesicles and do not decorate the synaptic vesicles. In the median eminence gold labeled fibers are detected in all layers. The labeled fibers can be closely apposed to tanycytic processes, without, however, forming special contact differentiations. In direction to the perivascular layer of the external zone the labeled profiles are more frequently arranged in groups intermingled with unlabeled fibers. The axons decorated with gold particles can be freely exposed to the perivascular space or are found as single processes in close vicinity to the capillary wall. Subsequent to preincubation of the native antiserum with ACTH1-39 and ACTH18-39 (= CLIP) neither adenohypophyseal cells nor perikarya and fibers in the arcuate nucleus nor axons in the median eminence are decorated with gold particles. Preincubation of the native antiserum with alpha-MSH or beta-endorphin does not change the immunoreaction with the small, peripherally situated granules in the branched adenohypophyseal cells. In neurons of the arcuate nucleus and in fibers of the median eminence, however, the immunoreaction is completely extinguished when the antibody is pre-incubated with alpha-MSH, whereas subsequent to preincubation with beta-endorphin only the amounts of labeled structures are reduced.(ABSTRACT TRUNCATED AT 400 WORDS)

The red pulp's argentophil reticular cell network of the spleen is composed by 3 types of fixed cells: 1. the primitive reticular cell, slightly argentophil; 2. the small reticular cell; 3. the larger reticular cell, strongly argentophil and phagocytic. This latter shows the classical morphological characteristics attributed to the reticular cells of the spleen. The large argentophil reticular cell may become free, constituting a 4th cell type, the free macrophage. A 5th reticular cell type is the dendritic cell found into the lymphatic follicles of the white pulp. The argentophil reticular cells of the red pulp assemble together to form the reticular cells' network, that occurs inside the red pulp cords. The primitive and the small reticular cell form the fundamental network on which the large cells are apposed. The reticular cells of this network maitain relationship with the arterial terminal vessels of the red pulp, being responsible by the ellipsoid structure. In those arteriolar segments without ellipsoid and in those mammalian species devoid of ellipsoid, the white pulp reticular cells, that surround the blood vessel as a part of the lymphoid periarteriolar sheath, mix with the red pulp's reticular cells and both can hardly be discriminated. The ellipsoids are formed by large argentophil cells arranged in concentrical layers around its lumen that sometimes appear devoid of endothelial lining cells. The red pulp's argentophil reticular cells, either the small or the large ones, contributed to the structure of the splenic sinuses' wall; its thin processes surround the sinus wall outside the endothelial lining cell as fibrillar structures that cross the back side of the lining cells. Two or more argentophil reticular cells send fibrillar processes to a single sinus. The perisinusal reticular cells may send a process between adjacent endothelial lining, cells that insinuate and attain the sinus lumen; this process becomes thick and eventually, the reticular cell enter the sinus lumen as a free macrophage. The argentophil reticular cells of the red pulp make connection between the capsule or the trabeculae and the reticular cell network. The endothelial lining cells of the splenic sinuses are not argentophil.

Fluoride-resistant acid phosphatase (extralysosomal) activity has been investigated in Pacinian sensory corpuscles from cat's mesentery. The activity was found in the innermost and intermediate layers of the capsular system, but it is not possible to establish its exact localization. The central axon and the inner core were FRAP negative. The authors discuss the possible functional significance of FRAP activity in sensory corpuscles.