On the innervation of the rat and pig adrenal cortex

Summary The innervation of the adrenal cortex of the rat and the pig is investigated with the electron microscope. Nerve fibers containing synaptic and two types of dense-cored vesicles come into contact with endocrine cells. There are no specialized pre- and postsynaptic membranes. The synaptic cleft is about 200 Å wide. Generally the basement membrane between nerve and cell is absent. These observations are discussed on the base of more recent experimental findings. Small fibers having an average diameter of about 0.2 to 0.5 and containing only tubules and filaments are considered to represent parts of an afferent nervous system.Dedicated to Prof. v. Kügelgen on the occasion of his 60th birthday.Supported by the Deutsche Forschungsgemeinschaft.     

The fine structure of the pancreatic nerves of the domestic fowl

Summary The fine structure of the pancreatic nerves of the domestic fowl has been studied. Naked axon beadings were found in membranous contact with endocrine as well as exocrine cells. From an anatomical point of view it seems reasonable to suggest that the endocrine glands might be subjected to some influence of the autonomic nervous system.     

Innervation patterns of the cerebral nerves in <Emphasis Type="Italic">Haminoea hydatis</Emphasis> (Gastropoda: Opisthobranchia): a test for intraspecific variability

This study describes the innervation patterns for the cerebral nerves which project to the cephalic sensory organs (CSOs) in the opisthobranch Haminoea hydatis (Linnaeus 1758) and uses axonal tracing techniques (backfilling) to reveal the central cellular origins for these cerebral nerves. Cell clusters projecting into the cerebral nerves can be defined by their positions in the ganglion relative to other clusters, nerve roots and lobes. The number of cell clusters and the relative sizes of somata are constant in a given cluster, whereas the absolute number of somata and absolute sizes of single somata in a given cluster increase with the size of the animal. Additionally, the invariable morphological characteristics of the cell clusters are used to define criteria for the assessment of possible homology for the clusters innervating the CSOs in Opisthobranchia. The data suggest two different strategies to accommodate the increasing body size; first, the additions of nerve cells and second, the growth of nerve cells. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Innervation zones location and optimal electrodes position of obliquus internus and obliquus externus abdominis muscles

The assessment of abdominal muscles has became popular in recent years because the study of “core muscles” is now considered a pivotal approach for a number of fields. The purpose of this study was to describe the innervation zone (IZ) locations and optimal electrode sites in two core muscles: the obliquus externus (OE) and the obliquus internus (OI) abdominis muscles. Twenty healthy male subjects were recruited and the IZ location was studied during a submaximal isometric contraction using multichannel surface EMG.The optimal electrode position for OI was found to be 2 cm lower the most prominent point of the anterior superior iliac spine, just medial and superior to the inguinal ligament. The optimal electrode position for OE was found to be 14 cm from the median line, lower the level of 1 cm above umbilicus, parallel to the line extending from the most inferior point of the costal margin to the opposite pubic tubercle (almost 45° with respect to the median line).Findings showed that for OI and OE muscles it is possible to provide indications for a muscle belly area suited for proper positioning of at least an electrode pair.     

自发性高血压鼠脑内血管的单胺能神经分布

采用ＡＢＣ免疫过氧化物酶法,以酪氨酸羟化酶（ＴＨ）作为标记物,对８只雄性自发性高血压鼠（ＳＨＲ）和４只正常血压鼠（ＷＫＹ）作为对照组脑实质内血管的中枢去甲肾上腺素能神经分布进行了观察。在自发性高血压鼠的端脑皮质、下丘脑、脑桥实质内血管均可见呈棕褐色,似单一细线状结构的免疫反应阳性纤维。测量了各部脑实质内血管的纤维密度,与正常血压鼠同部位脑实质内血管上的纤维密度比较明显增大。经统计学处理,各部Ｐ值均＜０．０５,表明在高血压鼠和正常血压鼠脑实质内血管的中枢去甲肾上腺素能纤维的密度有明显的差异。这可能为高血压鼠较正常血压鼠有更高的交感神经活性提供一个形态学基础,并提示交感神经在自发性高血压鼠的高血压维持和发展方面起着重要的作用。     

Concordance of the location of the innervation zone of the tibialis anterior muscle using voluntary and imposed contractions by electrostimulation

Background: The innervation zone (IZ) corresponds to the location of the neuromuscular junctions. Its location can be determined by using arranged surface linear electrode arrays. Typically, voluntary muscle contractions (VC) are used in this method. However, it also may be necessary to locate the IZ under clinical conditions such as spasticity, in which this type of contraction is difficult to perform. Therefore, contractions imposed by electrostimulation (ES) can be an alternative. There is little background comparing the locations of IZ obtained by two different types of contractions. Objective: Evaluate the concordance between using voluntary and imposed contractions from electrostimulation in order to determine the location of the innervation zone of the tibialis anterior muscle in healthy volunteers. Methods: The tibialis anterior (TA) muscle of sixteen volunteers (men: 8; women: 8; age: 22.1 ± 1.4 years, weight: 61.6 ± 7.5 kg, height: 167.1 ± 7.5 cm) were evaluated using a linear electrode array. The IZ of the TA muscle was located using two types of muscle contractions, voluntary (10% MVC) and imposed contractions by ES. The concordance between both conditions was evaluated using the Bland–Altman method and the concordance correlation coefficient (CCC). The analyses were applied to the absolute and relative positions to the length of an anatomical landmark frame. Results: CCC for absolute position was 0.98 (p < 0.0001, 95% CI [0.98–1.00], and CCC for relative positions also was 0.98 (p < 0.0001, 95% CI [0.97–1.00]). The Bland–Altman analysis for absolute data showed an average difference of −0.63 mm (SD: 4.1). Whereas, for adjusted data, the average difference was −0.20% (SD: 1.2). The power of the results, based on absolute data, was 98%, whereas for relative data, 82%. Conclusion: In healthy volunteers, there was a substantially concordance between the location of the IZ of the TA muscle derived from using contractions imposed by ES and the location derived from using VC.     

The ultrastructure of the intestinal nerve of Remak in the domestic fowl

Summary An ultrastructural study was made of the neurons, satellite cells and vesiculated axons of the intestinal nerve of the domestic fowl. Broad membrane-to-membrane contacts between adjacent nerve cell bodies were sometimes observed. The cell bodies and processes were not always separated from the extracellular space by a capsule of satellite cells. Following fixation using potassium permanganate, catecholamine (CA)-containing neurons in the intestinal nerve, unlike those in the lumbar parasympathetic ganglia, did not possess any small granular vesicles (SGV). Following exposure to noradrenaline, SGV could be demonstrated in the cell bodies of the juxta-ileal ganglia but not the juxta-rectal ganglia of the intestinal nerve. Non-CA axons were examined in tissue from birds that had been pretreated with 6-hydroxydopamine. Approximately one half of the non-CA axons formed axo-somatic contacts. Most of the non-CA axons contained varying proportions of small clear vesicles, large clear vesicles and large granular vescles. Statistical analysis showed that the non-CA axons could not be subdivided according to their vesicle content. CA-axons contained many SGV and were found in close apposition to neuronal somata and processes, and in the neuropil.     

Ultrastructure of the neurosecretory system of the Colorado potato beetle,Leptinotarsa decemlineata (Say)

Summary The ultrastructure of seven types of neurosecretory cells (NSC) in the medial and lateral groups of the protocerebrum is described. The differences among cell types established earlier by light microscopy parallel differences in size and appearance of the neurosecretory particles observed in electron micrographs. No relationship was found between the affinity for Gomori's paraldehyde fuchsin stain and the nature of the particles.The secretions of the A-, A₁-, and C-types of NSC of the medial group are characterized by electron-dense neurosecretory granules of 1250 Å dia., medium-dense granules of 2100 Å, and electron-lucent vesicles of 1700 Å, respectively. The L-type NSCof the lateral group contain smaller (1300 Å) or larger (1700 Å) neurosecretory granules. The medial B- and E-types of NSC and the lateral L_B-type contain granulated vesicles (1200 Å) of the same appearance. These cell types differ in other respects and most likely have separate functions.The author wishes to thank the Laboratory of Virology of the Agricultural University for the use of the electron microscope, Mr. J. Groenewegen and Miss J. van Rinsum for technical assistance, and Professor J. Lattin for correcting the English text. Part of the work has been done while the author was in the service of the Netherlands Organization for the Advancement of Pure Research (ZWO, grant 942-48), and the National Council for Agricultural Research (TNO).     

Electron microscopic investigation of adrenergic and non-adrenergic axons in the rabbit SA-node

Summary The rabbit SA-node was outlined electrophysiologically and its adrenergic and cholinergic innervation patterns were studied with the electron microscope. Differentiation between adrenergic and cholinergic terminals was achieved by fixation of the specimens in KMnO₄ which produces dense-cored synaptic vesicles in adrenergic terminals, whereas synaptic vesicles in cholinergic terminals are empty. It was found that adrenergic and cholinergic nerve terminals often come in close apposition to each other, the distance between adjoining membranes being in the order of 250 Å. At times, faint membrane thickenings could be seen in these places. The available pharmacological, physiological and morphological evidence leaves little room for doubt that cholinergic terminal fibers can influence the adrenergic ones. From mainly morphological evidence it is also postulated that adrenergic terminals influence cholinergic terminals.This work was supported by grants from Åhlén-Stiftelsen, the Faculty of Medicine, University of Lund, Lund, Sweden, the United States Public Health Service (project 06701-04) and the Swedish Medical Research Council (B70-14X-2321-03 and B70-14X-712-05).     

Zur Ultrastruktur der Chromatophorenmuskelzellen von Loligo vulgaris

Zusammenfassung Die Innervation der braunen, roten und gelben Chromatophoren von Loligo vulgaris ist quantitativ und qualitativ verschieden. In den begleitenden Nervenbündeln finden sich stets Axone mit hellen (etwa 300 Å Ø), gelegentlich auch solche mit dense-core-Vesikeln (etwa 600 Å Ø).Die Myofilamente der kontraktilen Rinde sind gegeneinander versetzt und um die Längsachse spiralig gewunden. Im axialen Sarkoplasma treten gebündelte, in Längsrichtung zur Muskelzelle orientierte Filamente auf (jedes etwa 70 Å Ø), die möglicherweise eine Funktion bei der tonischen Kontraktion erfüllen.

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The ultrastructure of chromatophore muscle cells in Loligo vulgaris

Summary The innervation of the brown, red and yellow chromatophore muscle cells in Loligo vulgaris shows quantitative and qualitative differences. The nerve bundles regularly contain axons with electronlucent vesicles of about 300 Å diameter, and occasionally axons with dense core vesicles of about 600 Å diameter. The myofibrils of the contractile cortex show a staggered arrangement and are wound in a spiral with respect to the axis of the muscle cell. In the axial sarcoplasm there is additionally a bundle of thin filaments of about 70 Å thickness. The bundle is orientated in parallel with the longitudinal axis of the muscle cell. Its function may be to maintain tonic contractions.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.