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W Breipohl

Publications and source records attributed to W Breipohl.

At least 37 records · Page 2Linked to original sources
PubMed1991

Growth hormone receptor expression in the Dunning R 3327 prostatic carcinoma of the rat.

The Dunning R3327 rat carcinoma is an important model for human prostate adenocarcinoma. In the present study this tumor was further characterized by immunohistochemical demonstration of receptors for growth hormone (GH-R). Weak GH-R immunoreactivity was present in the secretory epithelial cells of the tumor acini. Large epithelial cells which were localized at the periphery of the acini and large cells in the stroma, which are probably derived from the epithelium ("Large neoplastic epithelial cells"), displayed a strong staining with one of the monoclonal antibodies (Mab 263) to GH-R. The presence of GH-R receptors in proliferating prostatic tumor cells supports the concept that GH reacts directly on prostate target tissue to facilitate tumor cell growth.

Animals↗
PubMed1991

Identification of endogenous sugar-binding proteins in the accessory sex glands of NMRI mice. A histochemical and biochemical study.

In the present study we report on the histotopographical distribution of carbohydrate-binding proteins in the prostate and seminal vesicle of sexually mature NMRI mice using a panel of fluorescein-isothiocyanate labelled neoglycoproteins and asialoglycoproteins. Additionally, biochemical analysis using affinity chromatography and SDS-gel electrophoresis was performed to purify and characterize the respective proteins from the tissue. Our histochemical results clearly demonstrate the presence of endogenous receptors for the carbohydrate part of glycoconjugates in both glands. In the prostate a distinct staining was seen after incubation with melibiose-BSA-FTC, glucuronic acid-BSA-FTC and asialofetuin-FTC (only in the ventral prostate). In the epithelium of the seminal vesicle a weak staining occurred after incubation with asialofetuin-FTC and maltose-FTC. In the stroma of both accessory sex glands a distinct binding of several (neo)glycoproteins specific for beta-galactoside-binding proteins was observed which could be attributed to a beta-galactoside-binding lectin. Indeed biochemical analysis ascertained presence of such a histochemically detectable activity. We assume that the carbohydrate-binding proteins of the stroma, which were obviously linked to the elastic fibers, could play a role in the organisation of the extracellular matrix in the interstitium of the glands.

Animals↗
PubMed1991

Morphological investigations on the small intestinal mucosa of mouse after mild hyperthermic treatment.

Local hyperthermia, when applied as a therapeutic agent against radio-resistant tumours, can result in serious side effects in adjacent non-tumorous tissue, one especially thermo-sensitive organ being the small intestine. An experimental morphological study was therefore undertaken with mice to investigate whether "mild hyperthermia" (41 degrees C for 15, 30 and 60 min) causes alterations at the mucosa of the small intestine, and if so what are these effects and their likely pathomechanisms. Descriptive light and electron microscopical studies and morphometric evaluations are reported on the jejunal mucosa. The observed changes were most extensive after 60 min of 41 degrees C hyperthermia; but even 30 and 15 min hyperthermic treatment was followed by severe degenerative changes. The epithelium of the basal crypts and the stromal cells seemed to remain morphologically unaffected under these conditions, though the stroma can react with a temporary contraction. No "prime event" in the hyperthermia provoked tissue changes can be deducted from the combined light, electron microscopical, and morphometric studies. Comparing, however, the extent of the effects after mild hyperthermia of 60, 30 and 15 min, respectively, four phases of intestinal alterations due to mild hyperthermia and a likely pathomechanism of this treatment can be defined. The clinical implications of the findings are discussed.

Animals↗
PubMed1990

Growth hormone receptor expression in the rat gastrointestinal tract.

We have used immunohistochemistry to define the cellular distribution of GH receptors in the gastrointestinal tract (GIT) and its derivatives. Immunohistochemistry was performed in the adult rat GIT with a panel of characterized monoclonal antibodies to the GH receptor. The most intense and heterogeneous immunoreactivity was observed in epithelial cell subpopulations of GIT mucosa. Mesenchymal elements of the GIT were homogenously and moderately immunoreactive. Intense immunoreactivity was observed in the ductal epithelium of the sublingual gland, scattered basal epidermal cells of the esophageal mucosa, zymogen cells of the gastric glands, scattered surface epithelial cells of the stomach, and scattered peripheral pancreatic acinar groups. Scattered enteroendocrine cells and parietal cells, crypt and villous columnar cells of the small intestine, surface columnar cells of the cecum/colon, crypt base columnar cells of the colon, and contiguous peripheral cords of pancreatic islet cells displayed strong immunoreactivity. No immunoreactivity was detectable in the mucous and serous acini of the sublingual and submandibular gland, respectively, mucous-secreting cells of the base of the cardiac and pyloric glands, surface epithelial cells of the fundus, paneth cells, goblet cells of cecum/colon, or mucous cells at the base of the cecal crypt. Other elements of the GIT were moderately or weakly immunoreactive. In support of our localization we can detect high affinity binding (Ka = 3 x 10(9] of [125I]human GH with ovine GH as displacing ligand to crude homogenates of adult rat stomach and intestine. We conclude that discrete epithelial cell subpopulations of the GIT and its derivatives are directly responsive to GH action. GH may, therefore, act independently of or synergistically with hepatic insulin-like growth factor-I in executing its physiological and/or growth-promoting role in the GIT.

Animals↗
PubMed1990

Cellular localization of the growth hormone receptor/binding protein in the male and female reproductive systems.

We have used immunohistochemistry to localize GH receptor/binding protein (BP) in the male and female reproductive systems of adult rats. Testes and ovaries from neonatal animals were also examined to determine if GH receptor/BP expression in these tissues is developmentally regulated. Two monoclonal antibodies (MAb 43 and 263) were immunoreactive in identical locations whereas no immunoreactivity was evident when control monoclonal antibodies 7 and 50.8 were used. Localization of the receptor/BP was observed in both the nucleus and cytoplasm of immunopositive cells confirming our recent report of a nuclear GH receptor. Intense GH receptor/BP immunoreactivity in the male reproductive system was evident in the epithelium of the vas deferens and coagulating gland, the prostatic epithelium during the secretory phase, and the ductular epithelium of the coagulating and bulbourethral glands, respectively. Strong immunoreactivity was detectable in the Leydig and Sertoli cells, the epithelium of the ductus epididymis and seminal vesicles and smooth muscle of the tunica muscularis of the vas deferens, septae of the seminal vesicles, and in prostatic fibromuscular stroma. Cells of the seminiferous tubules (spermatogonia, primary and secondary spermatocytes, and spermatids) were moderately immunoreactive. No immunoreactivity was detectable in spermatozoa in the ductus epididymis or vas deferens, in scattered epithelial cells of the ductus epididymis, the prostatic epithelium in the nonsecretory phase, and mucous secreting cells of the bulbourethral glands. Leydig cells of 10-day postnatal rat testis were intensely immunoreactive whereas seminiferous tubular cells displayed homogenous immunoreactivity from moderate to strong. Intense GH receptor/BP immunoreactivity in the female reproductive system was evident in the germinal epithelium, the vascular endothelium of the myometrium, the epithelial lining of the fimbriae and oviduct, the endometrial epithelium and scattered endometrial glands, the mesothelium of the perimetrium, and the vascular endothelium of the endometrium. Strong immunoreactivity was exhibited by scattered oocytes, lutein cells of the corpus luteum, scattered endometrial glands, and the vascular endothelium of the endometrium. Moderate immunoreactivity was evident in scattered oocytes, granulosa cells, theca interna and externa, smooth muscle of the oviduct and myometrium, scattered endometrial glands, and luminally placed endometrial stroma cells. Ovarian granulosa cells from 10-day postnatal rats displayed strong immunoreactivity in contrast to moderate immunoreactivity in adult granulosa cells. In conclusion, we report a widespread distribution of the GH receptor/BP in the reproductive system of the rat by which GH may exert a direct action on reproductive function. The distribution is concordant with a role for GH in epithelial function and/or maintenance and also with a possible role for GH in the integrity of the endometrial vasculature.

Animals↗
PubMed1990

Localization of the growth hormone receptor/binding protein in skin.

Acromegaly is characterized by coarsening of facial features, acanthosis nigricans, hypertrichosis and oily skin. To determine the site through which GH exerts these effects, we have used immunohistochemistry to localize the GH receptor/binding protein (BP) in rat, rabbit and human skin. Three monoclonal antibodies (MAb 1, 43, 263) were immunoreactive in identical locations, whereas no immunoreactivity was evident when control monoclonal antibodies (MAb 50.8 and MAb 7 (rat] were used. Skin from neonatal and adult animals was used to determine whether GH receptor/BP expression was developmentally regulated. Immunoreactivity of the GH receptor/BP in the three species was consistently localized in the stratum basale and stratum spinosum. Intermittent staining was observed in the stratum granulosum. Scattered basal epidermal cells often displayed more intense immunoreactivity. This distribution was observed at all maturational stages examined. Intense GH receptor/BP immunoreactivity was observed in all histological layers of the lower one-third of hair follicles and in hair matrix cells of the dermal papillae. Immunoreactivity was also detected in the outer epithelial root sheath of the upper two-thirds of hair follicles, in sebaceous glands and in fibroblasts of the connective tissue sheath surrounding the follicle. GH receptor/BP immunoreactivity was also present in the secretory duct and myoepithelial cells of human eccrine sweat glands. Fibroblasts, Schwann cells of peripheral nerve fascicles, skeletal muscle cells and adipocytes of the dermis were also immunoreactive as were medial smooth muscle and endothelial cells of arteries. These results provide evidence that GH acts locally on the epidermis and epidermal appendages concordant with our recent localization of GH receptor/BP to epithelial cell types of the gastrointestinal and reproductive systems.

Animals↗
PubMed1988

Spine density on olfactory granule cell dendrites is reduced in rats reared in a restricted olfactory environment.

The Golgi technique was used to study the development of spines on the external dendrites of granule cells in the olfactory bulbs of young rats that had been continuously exposed to cyclohexanone vapor, deodorized air, or rat odors. Exposure to deodorized air for 3 weeks from postnatal day 1 reduced spine density on the medial and lateral sides of the bulb, whilst exposure to cyclohexanone reduced spine density on the lateral side only. These reductions were evident in other animals exposed for 7 weeks. With all treatments, spine density reached a maximum at postnatal day 21 and decreased markedly during the next month.

Age Factors↗
PubMed1988

Cell dynamics in the olfactory epithelium of the tiger salamander: a morphometric analysis.

The factors controlling neurogenesis and differentiation of olfactory receptor cells in adults are poorly understood, although it is often stated that these cells undergo continual turnover after a predetermined lifespan. An interesting model in which to study mechanisms which control olfactory receptor neurogenesis and cell turnover is the tiger salamander, since basal cell mitosis varies with epithelial thickness and location in the nasal cavity. This paper presents a quantitative light-microscopic study of the different cell types within the ventral olfactory epithelium of the tiger salamander using a computer-assisted morphometric analysis of 2 micron sections. The results show that the surface density of olfactory vesicles remained constant throughout most of the epithelium and was independent of nasal cavity location, epithelial thickness and the total number of nuclei per unit epithelial surface area. Histological classification of nuclei into different cell types indicated that the increase in total cell number with epithelial thickness was mainly due to an increase in the number of immature receptor cells since the number of supporting cells varied only slightly and the numbers of basal cells and mature receptor cells remained constant except in the thinnest, most caudally located epithelium. It is concluded that the rate of maturation of receptor cells may be limited by an optimal surface density of olfactory vesicles. That is, when this density reaches 4.5 x 10(4) vesicles per mm2 there is a physical or chemical mechanism which prevents the final maturation of newly developing receptor cells, leading to their accumulation. This mechanism may also account for the variations in basal cell mitosis in this species.

Animals↗
PubMed1988

Freeze-fracture analysis of the respiratory cilia from the bronchial mucosa of a patient with primary ciliary dyskinesia.

Respiratory cilia of the bronchial mucosa from a 5-year-old boy with clinical evidence of classical Kartagener's syndrome (situs inversus, bronchiectasis and sinusitis) were first examined by means of transmission electron microscopy for identification of the axonemal defects described as typical for primary ciliary dyskinesia (PCD). Additional oscillography was performed on the cilia in vitro, which showed absence of a coordinated ciliary beat frequency. After clear classification of the case as PCD, a freeze-fracture examination of the respiratory cilia was performed, which revealed a higher density of intramembrane particles on the outer fracture face (E-face) than on the inner fracture face (P-face). The results were discussed with regard to probable pathogenetic aspects on PCD.

Biopsy↗
PubMed1987

Differential immunocytological expression of a paraprotein-associated idiotype is possibly related to variant immunoglobulin molecules in plasmacytoma cells.

An anti-idiotype antibody (anti-Id Ab) was made by immunization of a rabbit with the IgG-2/lambda paraprotein from a plasmacytoma patient (Sa). The antibody was directed against determinants of heavy (H) and light (L) chains on the F(ab)2 piece of the paraprotein. Using this antibody an unusual pattern of cytoplasmic fluorescence was seen with bone marrow cells of the patient. One population (type I) showed reactivity in association with gamma and lambda chains, the other (type II) with the anti-Id Ab only. So, by immunological methods, biclonality could be demonstrated using the anti-Id Ab but not with anti-isotype antibodies. L chains of mol. wt 23.5 and 17.0 kd were observed. The H and L chains of small molecular weight were not detected in the patient's serum nor in the culture supernatant. Thus, deleted and intracellularly degraded H and L chains may cause the unusual staining pattern of the type II cells.

Antibodies, Anti-Idiotypic↗
PubMed1986

Changes in granule cells of the ferret olfactory bulb associated with imprinting on prey odours.

The maturation of the granule cells of the ferret olfactory bulb around the time of odour imprinting has been examined. Rapid Golgi impregnation studies revealed a temporal overshoot in the development of the spines on the external and internal dendrites of the granule cells. In contrast, the number of somatic spines decreased continuously. Electron microscopical examinations of the synaptic contacts in the external plexiform layer revealed that the time course of synapse and reciprocal synapse formation was similar to that of the formation of the spines on the external dendrites. The results were taken as evidence that both the Golgi and the electron microscopical investigations described the same developmental process of postnatal synaptic rearrangement.

Animals↗
PubMed1984

Freeze-fracture study of the plasma membranes of the septal olfactory organ of Masera.

The olfactory border and the apical cell contacts of the organ of Masera (MO) of the mouse were investigated by freeze-fracture electron microscopy. The olfactory border is mainly composed of the terminals of receptor and supporting cells. Cells with thick microvillus-like projections, though less frequent than the other two cell types, also contribute to the border. Olfactory knobs show transitions between those displaying numerous cilia and those characterized by few or no cilia. The olfactory cilia have a typical necklace of 6-9 rows of particles. The eruption of developing cilia seems to be preceded by the formation of circular arrays of particles. The density of intramembranous particles (IMP) per micron2 in P- and E-faces of the ciliary membranes is 1095 +/- 190 and 205 +/- 65, respectively. In the microvilli of supporting cells, the density of IMP per micron2 is 1800 +/- 270 for the P-face and 570 +/- 135 for the E-face. At the base of the supporting cell microvilli, rod-shaped particles are observed. The lateral plasma membranes of these cells bear orthogonal arrays of particles. In the apical region of the MO neuroepithelium, extensive zonulae occludentes are present which seal the intercellular cleft. The zonulae occludentes between supporting and receptor cells are composed of 5-13 junctional strands, usually arranged in an elongate network. Zonulae occludentes between supporting cells are, in addition to the elongate network, also arranged in a mesh-like pattern. Gap junctions, both associated with the zonulae occludentes and independent of them, are occasionally found between supporting cells. The results obtained indicate that important similarities exist between the neuroepithelium of the MO and the olfactory epithelium proper, whereas remarkable differences exist between the MO and the vomeronasal neuroepithelium.

Animals↗
PubMed1983

The cell coat of the olfactory epithelium proper and vomeronasal neuroepithelium of the rat as revealed by means of the Ruthenium-red reaction.

The apical cell coat of the olfactory epithelium proper and the vomeronasal neuroepithelium of the rat was investigated electron-microscopically by means of the Ruthenium-red reaction. In the olfactory epithelium proper, the cilia of receptor cells and microvilli of supporting cells possess a cell coat measuring approximately 10 nm in thickness. In the vomeronasal neuroepithelium, the apical cell coat is thicker than in the olfactory epithelium proper. On microvilli of vomeronasal receptor cells the cell coat varies in thickness from 15 to 20 nm, and on microvilli of supporting cells it measures approximately 75 nm. The functional implications of these findings are discussed.

Animals↗
PubMed1982

The vomeronasal epithelia of NMRI mouse. A scanning electron-microscopic study.

The features of the apical and lateral surfaces of cells of the vomeronasal epithelium were studied in adult male mice by scanning electron microscopy. Supporting cells and receptor cells of the neuroepithelium are covered with microvilli. Microvilli of the sensory cells are longer and thinner than those of the supporting cells. Additionally, the former differ in local distribution, orientation, occurrence of branching and appearance of the cell coat. The receptor-free epithelium consists most likely of one cell type only, which shows different structural modifications including the presence, number and length of microvilli and cilia. In the transitional region, between the neuroepithelium and the receptor-free epithelium, immature receptor cells are present.

Animals↗
PubMed1982

Effect of N-methyl-formimino-methylester on the vomeronasal neuroepithelium of mice.

N-methyl-formimino-methylester (MFM), a highly volatile chemical substance, causes massive, transient sensory-cell degeneration in the main, but not in the vomeronasal olfactory sensory epithelium of mice. After MFM-treatment it appears possible to study the accessory olfactory system after chemical "deafferentation" of the main system.

Animals↗