Null cell adenomas of the pituitary gland. An immunohistochemical study

Fourteen null cell adenomas of the pituitary gland were examined immunohistochemically with antisera against three general neuroendocrine markers and 22 hormones. All cases showed positive immunostaining for neuron-specific enolase, ten cases for synaptophysin, and six cases expressed chromogranin immunoreactivity. Hormone immunoreactivity was detected in a few cells in ten of the 14 cases studied and the number of hormones demonstrated in each case was one or two. Thyroid-stimulating hormone was detected in five of the 14 cases, gastrin in four, beta-endorphin in two, calcitonin gene related peptide in one, prolactin in one, and follicle-stimulating hormone in one.     

Mechanics of transport of the ovum in the oviduct

Although the forces leading to ovum transport in the oviduct cannot be measured experimentally, their magnitudes can be estimated analytically. Using anatomical and physiological data, with biomechanical tools, it has been demonstrated that, under normal circumstances, the drag caused by fluid, set in motion by wall peristalsis, is the primary propelling force. This force may lead to back-and-forth motion, but the net movement is in the forward direction. Segmental contraction, fluid circulations due to ciliary beat and the force due to brushing action of cilia on the ovum, are of minor significance. When wall peristalsis is inhibited, cilia activity may lead to ovum movement at near normal rates.     

Fetal bovine oviduct epithelial cell monolayers: Method of culture and identification

Summary Bovine epithelial cell monolayers were obtained for culture from fetal oviduct after in situ trypsinization. Isolated ciliated and secretory cells obtained in high yield with good viability were suspended in B2-MENEZO'S medium supplemented with 7.5% fetal bovine serum FBS. The plated primary cultures reached confluency 2 days after initial seeding, producing a monolayer of cohesive polygonal cells with viability of 85 to 95%. Associated with this large epithelial cell population, ciliated cells as well as a few elongated spindle cells were observed. After the first subculture the ciliated cells disappeared and the epithelial cells in the monolayer grew more rapidly to confluence than adult-derived cultures. In addition, frozen-thawed oviduct epithelial cells also maintained a level of 75 to 85% viability during postthaw subculture. The epithelial cells maintained their secretory activity in culture as indicated by electron microscopy and immunocytochemistry. The cell culture monolayers contained keratin, a specific cytoskeletal component of epithelial cells. This culture system may offer benefits for in vitro culture of mammalian embryos. This research was supported by the Mérieux Foundation.     

Effects of Ca2+ on the contractility and Sr2+ accumulation in the quail oviductal smooth muscle

There occur strong spontaneous contractions in the avian oviduct, which are considered to effect the locus of the ovum during ovum transport. Previously it has been shown that stretch regulates these contractions by means of some unknown mechanisms in this tissue. When a transversal strip, cut from the proximal magnum of the oviduct, was first kept at the length (L₀= length in situ) and then stretched to the length 200% L₀ the total integrated area of contractions increased 3.67±0.63 (6) times greater (p<0.01) than the contractility at the length L_o. Ca²⁺ concentration of 5 mM increased the total integrated area of the contractions 1.42±0.22 (7) greater than the control while the increase at 8 mM was only 1.17±0.30 (7). 0.5 mM Ca²⁺ decreased the contractility to 0.72±0.15 (7). In a 50 μM EGTA containing solution, the contractility decreased in a few minutes. Sr²⁺ used as an indirect tracer of Ca²⁺ accumulated both in control and stretched strips in the sarcoplasmic reticulum, the mitochondria, and the sarcolemma. The electron-dense deposits were, however, most clearly seen in the sarcolemma. Compared to the Sr²⁺ accumulating sites in erythrocytes, deposits were on the outer side of the cell membrane, thus suggesting the glycocalyx as an important site for Ca²⁺ exchange in this smooth muscle. The sarcolemmal invaginations, caveolae, accumulated Sr²⁺ similarly to other parts of the sarcolemma. During ovum transport, stretch changes the Ca²⁺ accessibility to muscle cells, and at structural level, this takes place in the sarcolemma.     

Variable expression of tenascin‐C,osteopontin and fibronectin in inflammatory myofibroblastic tumour of the lung

Kaarteenaho R, Sormunen R, Pääkkö P. Variable expression of tenascin‐C, osteopontin and fibronectin in inflammatory myofibroblastic tumour of the lung. APMIS 2010; 118: 91–100. The aim of this study was to analyse the expression of tenascin‐C, osteopontin and fibronectin in inflammatory myofibroblastic tumour of the lung, which is a rare tumour of unknown aetiology. Nine patients with an inflammatory myofibroblastic tumour of lung were studied by immunohistochemistry for the presence of tenascin‐C, osteopontin, fibronectin and alpha‐smooth muscle actin, which is a common marker for myofibroblasts. The ultrastructure of myofibroblasts was confirmed by transmission electron microscopy. The expression of tenascin‐C, osteopontin, fibronectin and alpha‐smooth muscle actin was also studied by immunoelectron microscopy. All cases displayed all of the studied extracellular matrix proteins and also alpha‐smooth muscle actin‐positive spindle‐shaped fibroblastic cells that were undoubtedly myofibroblasts. The immunoelectron microscopic studies demonstrated labelling for alpha‐smooth muscle actin in intracellular filament bundles within myofibroblasts, for fibronectin in the extracellular filaments of the fibronexus and for tenascin‐C extracellularly often adjacent to myofibroblasts. Labels for osteopontin were observed within myofibroblasts and plasma cells. These results demonstrate that tenascin‐C, osteopontin and fibronectin were expressed in all three kinds of subtypes of inflammatory myofibroblastic tumours of the lung and further, variable amounts of myofibroblasts could be observed by light and transmission electron microscopy as well as by immunoelectron microscopic techniques.     

Ultrastructural Changes in Smooth Muscle Cells of the Small Intestine in Suckling Rabbits with Experimental Cholera

Ultrastructural study of the small intestine in suckling rabbits with experimental cholera revealed involvement of the inner and outer smooth muscle layers into the pathological process. Smooth muscle cells were characterized by vacuolar and fatty degeneration and focal colliquative necrosis. Apoptosis played little role in gastrointestinal motility disturbances. The presence of considerable amounts of fluid in intestinal loops reflects peristaltic dysfunction due to generalized damage to smooth muscle cells.     

A study on the effects of arsenic toxicity on oviduct histomorphology in the female rat

ABSTRACT

Arsenic-contaminated drinking water and its association to different diseases has been considered a severe problem worldwide. The goal of the present study was to evaluate the histopathological changes in oviduct of female rat following 4-week exposure to different doses (50, 100, and 200 ppm) of sodium arsenite. Treatment was initiated when rat reaches the age of 4 weeks. Body weight of animals was recorded weekly. Weight, diameter, and arsenic deposition in oviduct were estimated. Based on anatomical division of oviduct, histology of isthmus and ampulla was examined for any histopathological changes. A dose-dependent decrease was observed in body weight and oviduct weight of treated rats as compared to untreated control rat and low-dose group. Higher arsenic deposition was found in oviduct with the increased doses of arsenite. Cellular arrangement was found disorganized and loosely packed in the epithelium and muscle layers of all treated groups, but was more conspicuous at 200 ppm dosage. Fewer cilia were seen in isthmus and ampulla of treated groups, and almost no cilia were observed in isthmus of 200 ppm group. Muscle layer thickness and epithelium height of arsenic treated rats was reduced in a dose-dependent manner from low (50 ppm) to high group (200 ppm) as compared to control rats. This study found that arsenite treatment adversely affected the body weight of female rats and induced histopathological changes in the cellular structure, configuration, and organization of oviduct in female rats.     

Analysis of ciliary beat frequency and ovum transport ability in the mouse oviduct

The oviduct is important in reproduction where fertilization occurs, and the fertilized eggs are conveyed to the uterus. Multi‐ciliated cells of the oviductal epithelium and muscle contractions are believed to generate this unidirectional flow. Although there are many studies in human oviducts, there are few reports on mouse oviductal ciliary movements where we can dissect underlying genetic programs. To study ciliary movements in the mouse oviduct, we exposed the ovary‐side of the oviduct (infundibulum) longitudinally and recorded the ciliary beatings in a hanging drop preparation. We calculated the ciliary beat frequency (CBF) by automated image analysis and found that the average CBF was 10.9 ± 3.3 and 8.5 ± 2.5 Hz (±standard deviation) during the diestrus and estrus stages, respectively. Mapping of the CBF to multiple locations in the epithelium showed that the cilia beat regularly at a local level, but have a range of frequencies within the entire plane. We also observed ova with cumulus cells were transported to the uterus side by the opened oviduct at the diestrus and estrus stages. These results suggest that the ciliated cells of the infundibulum can generate unidirectional flows and are able to deliver ova by their ciliary activities despite their discordance in beating periodicity.     

Correlation between electrical and mechanical activity in myogenic and neurogenic control of the bovine retractor penis muscle

The electrical and mechanical activity of fine bundles of the bovine retractor penis muscle (rp) were investigated with the sucrose-gap technique. The main results were: the muscle displayed prominent automaticity. It showed a vigorous and long lasting active response to stretch. Phasic contractions of the rp were associated with electrical firing while tonic contractions were not necessarily correlated to spike activity. Stimulation of excitatory nerves induced excitatory junction potentials (EJP). Single EJPs could elicit spikes and repetitive firing with long lasting contraction. The EJPs were abolished by phentolamine and adrenergic neuron blocking agents. Physostigmine suppressed EJPs while scopolamine and atropine enhanced them and counteracted the effect of physostigmine. This points to an endogenous neurogenic prejunctional muscarinic suppression of the excitatory adrenergic neurotransmission. Inhibitory nerve stimulation could produce an inhibitory junction potential (IJP). However, the inhibitory nerves may also act on the contractile process without an IJP as a necessary step.     

Intercellular contacts in tumours of the vascular smooth muscle cells in man

Summary Electron microscopy has been used to study the cell to cell and cell to stroma contacts between smooth muscle cells (SMC) in normal vessels, angiomyolipoma and well and poorly differentiated vascular leiomyosarcoma. Micrographs were examined with a semiautomatic image analysis system. The length of the cell borders was calculated and the type and number of contacts per 100 µm cell perimeter and per 100 cells were determined. In all cases there was a predominance of simple appositions. Intermediate junctions, nexus junctions, interdigitations, intermediate contacts and junctional interdigitations were less frequently observed. In general, as the SMC become malignant and less differentiated the number of cell to stroma attachments decreases markedly and the intercellular contacts increase slightly.     

Estrogen inhibition of noradrenaline release in the rabbit oviduct1

In the present study, we investigated the influence of estrogen on ³H-noradrenaline (³H-NA) release induced in the oviductal isthmus by electrical stimulation, potassium and calcium. The fractional release of ³H-NA was measured in oviducts isolated from ovariectomized rabbits and from ovariectomized rabbits treated with estradiol cypionate, 70 μg/kg im 72 h before an experiment. Electrical field stimulation of the intramural nerves induced muscle contraction and augmented the release of labelled NA from the muscle. The ³H-NA release was reduced after estrogen treatment when reuptake of NA into the nerve terminals was blocked by desipramine, 10^-6 M. Estrogen also reduced the ³H-NA release evoked by exposure of the oviducts to 121 mM KCI in the presence of calcium (2.5 mM) and in a high potassium, calcium-free medium upon the addition of 2.5 mM calcium. In the presence of desipramine a small fraction of ³H-NA was released in high potassium, calcium-free medium. This release was unaffected by estrogen. These results suggest that estrogen reduces the release of NA from the adrenergic nerves within the oviduct and that this action is exerted primarily on the calcium-dependent release. It therefore might be due to a reduction in the entry of calcium into the nerve terminal.     

Three‐dimensional architecture of the myosalpinx in the mare as revealed by scanning electron microscopy

The three‐dimensional architecture of the myosalpinx in the mare was investigated by means of scanning electron microscopy (SEM) after removal of interstitial connective tissue with NaOH digestion. In the extramural portion of the tubo‐uterine junction (TUJ), isthmus, and ampulla, the myosalpinx architecture is represented by a unique muscular structure which runs from the mesosalpinx to the base of the inner mucous folds. This unique muscular structure consists mainly of bundles of muscular fibers independent of one another, which show a multiple spatial arrangement and form a complex network. Such a muscular architecture is likely more suitable for stirring rather than pushing the embryos and gametes through the Fallopian tube. Anat Rec 267:235–241, 2002. © 2002 Wiley‐Liss, Inc.     

Malignant Smooth Muscle Tumors of the Gastrointestinal Tract: An Ultrastructural Study of 20 Cases

Twenty malignant soft tissue tumors arising from the stomach or intestine have been studied by light and electron microscopy, and the clinical records of each patient reviewed. The tumors were all considered to be of smooth muscle origin by light microscopy: Ten were spindle cell and ten were epithelioid neoplasms. By electron microscopy, only five tumors possessed smooth muscle features. A sequence of dedifferentiation could be traced among the remaining cases, indicating that the epithelioid tumors are of smooth muscle derivation. Awareness of the broad spectrum of fine structure displayed by these neoplasms will facilitate their ultrastructural identification.     

Malignant Smooth Muscle Tumors of the Gastrointestinal Tract: An Ultrastructural Study of 20 Cases

Twenty malignant soft tissue tumors arising from the stomach or intestine have been studied by light and electron microscopy, and the clinical records of each patient reviewed. The tumors were all considered to be of smooth muscle origin by light microscopy: Ten were spindle cell and ten were epithelioid neoplasms. By electron microscopy, only five tumors possessed smooth muscle features. A sequence of dedifferentiation could be traced among the remaining cases, indicating that the epithelioid tumors are of smooth muscle derivation. Awareness of the broad spectrum of fine structure displayed by these neoplasms will facilitate their ultrastructural identification.     

Peripheral ganglia supplying the genital smooth musculature in the female pig: an experimental study

The aim of the present study was to locate the sensory and autonomic ganglia innervating the female genital musculature in pigs. The retrograde neuronal tracers horseradish peroxidase (HRP) or fast blue (FB) were injected into the left retractor clitoridis muscle (RCM), which was treated as a typical model of the genital smooth musculature. Labelled cells were found in ipsilateral dorsal root ganglia Sl–S4, in bilateral sympathetic paravertebral ganglia from L5–L6 or L6–L7 to S3 and in the left and right caudal mesenteric ganglion. In two of the five animals treated, presumably preganglionic parasympathetic cells were labelled in the ipsilateral intermediate grey substance of the segments Sl–S2.     

Sensory nerve endings in the beak skin of Japanese quail

Summary This study is concerned with the distribution and ultrastructure of sensory nerve endings in the beak skin of adult Japanese quail (Coturnix coturnix japonica). The following nerve endings were found: free nerve endings, clusters of dermal Merkel nerve endings, Herbst corpuscles and Ruffmi corpuscles. The latter were found only in the dermis of the tip of the upper beak. The remaining endings were present in the skin of all areas of upper and lower beak. Free nerve endings were supplied by either thin myelinated axons or unmyelinated C-fibers and were localized in the dermis close to the basal layer of the epidermis. Merkel cells formed clusters (up to 50) localized below and between the epidermal cones of the beak skin. Disc-shaped thickenings of nerve endings were squeezed between individual Merkel cells. Small Herbst corpuscles were found in the dermis close to the epidermal cones of the beak skin. Large Herbst corpuscles occurred in deep layers of the dermis. The Ruffmi corpuscles were cylindrical in shape (80 m × 400 m) and arranged in groups of up to ten corpuscles. Each corpuscle was surrounded by an incomplete fibrous capsule.     

Wall cytoarchitecture of the rat ciliary process microvasculature revealed with scanning electron microscopy

Ciliary process vasculature has an important role in aqueous humor production. There have been, however, few reports describing the overall cytoarchitecture of ciliary process vasculature. The wall cytoarchitecture of microvessels in the rat ciliary process was elucidated by scanning electron microscopy after removal of ciliary epithelia and connective tissue components with HCl hydrolysis. Utilizing characteristics of cellular morphology and vessel diameters, several vascular components were identified along the vascular tree: 1) arterial iridociliary circles (30–60 μm in outer diameter), containing a compact layer of circularly oriented spindle‐shaped smooth muscle cells; 2) the proximal part of the radial ciliary arteriole (10–25 μm), containing a less compact layer of circularly oriented branched‐smooth muscle cells and spindle‐shaped smooth muscle cells; 3) a middle part of the radial ciliary arteriole (20–35 μm), with circularly oriented branched‐smooth muscle cells and irregularly oriented stellate cells with ramifying projections; 4) a distal part of the radial ciliary arteriole (10–20 μm), possessing irregularly oriented stellate cells with ramifying projections; 5) marginal venules (15–20 μm), with spidery pericytes possessing highly ramifying and overlapped projections; 6) capillaries in the ciliary process (4–7 μm), with widely scattered pericytes having longitudinal and several circular projections; 7) venules in the posterior basal region of the ciliary process (greater than 5 μm), with widely scattered pericytes having a few thin projections. From arterial iridociliary circles to venules in the basal region of ciliary process, seven parts could be recognized by wall cytoarchitecture, which was discussed in relation with the function. Anat Rec 254:261–268, 1999. © 1999 Wiley‐Liss, Inc.