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1.
The relationship between the intensity of combined formaldehyde-chloral vapour-induced fluorescence and the concentration of amino-terminal tryptophyl-peptide in model experiments was found to be non-linear. At a certain concentration the intensity began to increase more slowly than the concentration, and when the concentration further increased the intensity even began to decrease. Based on the studies previously reported and on the above findings it seems that fluorescence induced by combined formaldehyde-chloral vapour, glyoxylic acid vapour and possibly also other combined formaldehyde and carbonyl compounds in the hypophyseal cells containing amino-terminal tryptophyl-peptides is quenched in normal conditions due to the high local concentration. Thus, small to moderate changes in the amounts of amino-terminal tryptophyl-peptides cannot be observed by measuring the fluorescence intensity. In tissue experiments the intensity of combined formaldehyde-chloral vapour-induced fluorescence in the rat pars intermedia was measured after reserpine treatment, which decreases the number of hormone storage granules as demonstrated electron microscopically. The fluorescence intensity measurements were combined with an estimation of the amounts of amino-terminal tryptophyl-peptides extracted from hypophyses and separated in thin-layer chromatography, and subsequently demonstrated by combined formaldehyde-chloral vapour and a protein stain (amido black). Reserpine treatment decreased the fluorescence intensity in the pars intermedia and in thin-layer chromatography, and the staining of the fluorescent band with amido black was also decreased. Amino-terminal tryptophyl-peptides appeared to be depleted from the pars intermedia cells together with endorphins and other hormones of the ACTH/MSH cells containing tryptophan. 相似文献
2.
Seppo Partanen 《Histochemistry and cell biology》1978,56(2):147-154
Summary Methods for the isolation and thin-layer chromatographic identification of amino-terminal tryptophyl-peptides presumably responsible for histochemical tryptophyl-peptide reactions in the ACTH cells of the rat hypophysis are described. In the hypophyseal extract several tryptophylpeptide bands — depending on the homogenization solution — were demonstrated on thin-layer chromatograms. Tryptophyl-peptides were demonstrated from their fluorescence induced 1) with glyoxylic acid (glyoxylic acid introduced into the homogenization solution), 2) by exposure of the chromatographic plates to combined formaldehyde and chloral vapour or 3) by exposure to combined formaldehyde and acetyl chloride vapour. A positive PAS reaction was demonstrated in some tryptophyl-peptide bands. Thus, some tryptophyl-peptides seem to contribute to the observed PAS positivity of the ACTH cells.This investigation was supported by grants from the Jalmari and Rauha Ahokas Foundation and the J.K. Paasikivi Foundation 相似文献
3.
S Partanen 《Histochemistry》1978,56(2):147-154
Methods for the isolation and thin-layer chromatographic identification of amino-terminal tryptophyl-peptides presumably responsible for histochemical tryptophyl-peptide reactions in the ACTH cells of the rat hypophysis are described. In the hypophyseal extract several tryptophylpeptide bands--depending on the homogenization solution--were demonstrated on thin-layer chromatograms. Tryptophyl-peptides were demonstrated from their fluorescence induced 1) with glyoxylic acid (glyoxylic acid introduced into the homogenization solution), 2) by exposure of the chromatographic plates to combined formaldehyde and chloral vapour or 3) by exposure to combined formaldehyde and acetyl chloride vapour. A positive PAS reaction was demonstrated in some tryptophyl-peptide bands. Thus, some tryptophylpeptides seem to contribute to the observed PAS positivity of the ACTH cells. 相似文献
4.
Light and electron microscopic histochemical reactions were studied in the cells of pars intermedia of the rat. The possible correlations between enzymatic reactions and endocrine functions of these cells were discussed. By combined formaldehyde and chloral vapour treatment the cells of the pars intermedia exhibited a strong yellow fluorescence suggesting the presence of a peptide or peptides with NH2-terminal tryptophan. Masked metachromasia after acid hydrolysis was probably due to these peptides. Only a weak or no alpha-glycerophosphate dehydrogenase and nonspecific esterase activity was observed in the cells of pars intermedia compared to the cells of pars distalis suggesting low production rate of hormone synthesis. Specific and non-specific cholinesterases were demonstrated light and electron microscopically constantly in the cells bordering the lobules. These cells probably represent a certain type of glial cells. In the other cells the enzymatic activities varied markedly in intensity and distribution showing different ultrastructural localizations. Thus cholinesterase activities in the cells of pars intermedia reflect possibly different functional stages of the cells in their hormone production, storage and secretion processes. 相似文献
5.
Summary Light and electron microscopic histochemical reactions were studied in the cells of pars intermedia of the rat. The possible
correlations between enzymatic reactions and endocrine functions of these cells were discussed.
By combined formaldehyde and chloral vapour treatment the cells of the pars intermedia exhibited a strong yellow fluorescence
suggesting the presence of a peptide or peptides with NH2-terminal tryptophan. Masked metachromasia after acid hydrolysis was probably due to these peptides. Only a weak or no α-glycerophosphate
dehydrogenase and nonspecific esterase activity was observed in the cells of pars intermedia compared to the cells of pars
distalis suggesting low production rate of hormone synthesis.
Specific and non-specific cholinesterases were demonstrated light and electron microscopically constantly in the cells bordering
the lobules. These cells probably represent a certain type of glial cells. In the other cells the enzymatic activities varied
markedly in intensity and distribution showing different ultrastructural localizations. Thus cholinesterase activities in
the cells of pars intermedia reflect possibly different functional stages of the cells in their hormone production, storage
and secretion processes. 相似文献
6.
Summary ACTH and MSH cells of the pituitary are rich in peptides with NH2-terminal tryptophan, as revealed by fluorescence histochemistry. Adrenalectomy stimulates the ACTH cells but not the MSH cells. As a result, ACTH as well as tryptophyl-peptides disappear from the ACTH cells but not from the MSH cells. It is concluded that the tryptophyl-peptides are stored together with the respective hormone in the ACTH and MSH cells and that tryptophyl-peptides in the ACTH cells are released together with the hormone. 相似文献
7.
Summary In the neuro-intermediate lobe (NIL) of the eel, Anguilla anguilla, a specific formaldehyde-induced fluorescence, indicating a catecholamine (CA) innervation, has been demonstrated in the neural lobe processes. Microspectrofluorimetric analyses and pharmacological treatments indicate noradrenaline or dopamine or both to be responsible for the fluorescence.The fluorescence in the NIL has displayed a definite tendency toward variation during the adaptation to a white and to a black background. The highest amounts of fluorescence were generally found in animals adapted to a black background, especially when adapted for a rather long period, and in animals recently transferred to a white background. The lowest amounts of fluorescence were generally found in animals adapted to a white background.This and the result of injections of CA-depleting drugs suggest that the monoaminergic nerves are active when the animal is on a white background, inhibiting the MSH release directly or indirectly or both, or in co-operation with other factors.Specific green fluorescent structures were also found in other parts of the neural lobe supplying the pars distalis.In some pharmacologically untreated specimens and in animals treated with CA-depleting drugs, the intermedia cells fluoresced. Microspectrofluorimetric analyses indicated that this fluorophore was not a CA.We wish to express our sincere thanks to Miss Ingrid Carlsen for excellent technical assistance, Mr. Lajos Erdös for the photography and the technical staff of the Department of Histology in Lund. We are also indepted to Dr. Anders Björklund for valuable discussion and advice.Supported by grants from the Swedish Natural Science Research Council, the University of Lund, and the Royal Physiographic Society of Lund. 相似文献
8.
Summary The pars intermedia of intact and experimental female minks has been studied by light, electron and fluorescence microscopy. The general structure of the mink intermediate lobe is described. Two main cell types are recognized. One, termed glandular cell, predominates in number and is characterized by the presence of electron-dense granules about 200 nm in diameter and numerous large vesicles up to 300 nm in diameter. The other, termed stellate cell, is devoid of cytoplasmic vesicles and granules and possesses microfilaments, junctional complexes and elongated processes inserted between the glandular cells. Different treatments (photostimulation and administration of hypertonic saline and metopirone) induced morphological reactions in the glandular cells. The significance of these changes and the possibility of a functional relation between the pars intermedia and ACTH secretion are discussed.Numerous nerve fibres and axon terminals containing electron-dense granules (60–120 nm) and electron-lucent vesicles (30–40 nm) are observed throughout the pars intermedia.With the histochemical fluorescence method of Falck-Hillarp a rich system of delicate fluorescent varicose fibres, sometimes provided with irregular swellings or droplets, is observed in the pars intermedia and also in the pars nervosa. Microspectrofluorometrically these fibres exhibit the spectral characteristics of catecholamines. All the cells of the pars intermedia and a large number of cells in the pars distalis show a yellowish weak fluorescence, which becomes much stronger after combined formaldehyde-ozone treatment. This cellular fluorophore shows the same microspectrofluorometric characteristics as does the fluorophores of tryptamine and of certain peptides with NH2-terminal tryptophan.Supported by the Swedish Fur Breeders' Association and the Swedish Natural Science Research Council (grant No. 2124). Thanks are due to Miss W. Carlsson and Miss Y. Lilliemarck for their helpful technical assistance.Supported by the Harald and Greta Jeanssons Stiftelse and by the Ford Foundation. The skilful technical assistance of Mrs. Eva Svensson and Miss Annika Borgelin is greatfully acknowledged. 相似文献
9.
Summary Reserpine has a stimulatory effect on the pars intermedia of the rat pituitary, probably mediated by its action on regulatory catecholaminergic nerves. The effect of single intraperitoneal injections of 0.1–20 mg/kg b.w. of reserpine was studied in adult male rats. Reserpine at a dose of 2 mg/kg b.w. induced degranulation, orientation of the secretory granules along the cell membrane and loss of formaldehyde-chloral-induced fluorescence, accompanied by an activation of the granular endoplasmic reticulum and the Golgi apparatus. With higher doses progressive degranulation and loss of fluorescence were observed. The effect was, however, heterogeneous, and with all doses cells displaying normal ultrastructure and normal fluorescence were regularly present.To study the release of granular products (containing a different components of the pro-opiomelanocortin chain) from individual cells, formaldehyde-chloral induced fluorescence and -MSH- and -endorphin immunoreactivies were demonstrated in consecutive sections from pituitaries of rats given 8 mg/kg body weight of reserpine 24 h before sacrifice. The results indicate coordinated release of these granular products at the cellular level after reserpine treatment.This work was supported by Finska Läkaresällskapet 相似文献
10.
Pituitary sections from 15 to 21 day-old rat foetuses have been studied with the immunofluorescence technique, using antibodies anti alpha-MSH, anti beta-MSH and anti beta (1-24) ACTH. The first ACTH cells appear on day 17 of pregnancy in the pars distalis of the hypophysis and only on day 18 in the pars intermedia. beta-msh cells have been observed on day 16 in the pars anterior and on day 17 in the pars intermedia, while alpha-MSH cells appear only on day 18 and exclusively in the pars intermedia. The cytodifferentiation of the beta-MSH and ACTH cells occurs in the pars intermedia with about a 24 hours delay in comparison to that of the pars distalis. The first revealed cells are always located in the posterior half of the pituitary gland. The corticostimulating activity of the hypophysis has been tested with the fluorescence intensity of the corticotrophs, the adrenal weight, the adrenal content in corticosterone and the plasma corticosterone level. The fluorescence of the corticotrophs increases on day 18, shows a maximum on day 19 and decreases until term. The adrenal weight rises regularly between day 16 to day 20, thereafer the increase subsides. Adrenal and plasma corticosterone concentrations reach a peak on day 19 of pregnancy. These data suggest that hypophyseal corticostimulating activity is very high between days 18 and 19 and decreases between days 19 and 21. 相似文献
11.
Summary Light microscopy of coronal sections of the sheep pars intermedia revealed a compact, incompletely lobulated V-shaped region about 15–20 cells thick, situated between the pars distalis and the pars nervosa. A prominent hypophysial cleft and follicles containing a colloid-like substance were seen.Using electron microscopy, five cell types could be distinguished: pars intermedia glandular cells, pars distalis-like glandular cells, interstitial cells, follicular cells and cleft lining cells. The polyhedral to pear-shaped pars intermedia glandular cells predominated. They contained dense-cored, membrane-bound granules near the Golgi complex, and larger, irregular vesicles with finely granular contents of varying electron density throughout the remaining cytoplasm; exocytotic release of granules was occasionally observed. Smaller numbers of cells resembling those seen in the pars distalis were scattered throughout the pars intermedia. Interstitial cells usually possessed elongated cytoplasmic processes which extended between the glandular cells, and were characterized by deeply indented nuclei, elaborate junctional complexes and an absence of cytoplasmic granules. Cells lining the follicles resembled the interstitial cells. The major cells bordering the hypophysial cleft were triangular in section and bore irregular microvilli on their free surface. The pars intermedia appeared to be less vascular than the remainder of the hypophysis and only occasional fenestrated capillaries were seen. Nerve profiles were rare. 相似文献
12.
R. Håkanson F. Sundler A. Nobin N. -O. Sjöberg L. Edvinsson L. -I. Larsson 《Cell and tissue research》1974,150(2):281-290
Summary In the mammalian pituitary formaldehyde-ozone treatment induces strong fluorescence in the cells of the pars intermedia and moderate to strong fluorescence in numerous cells of the pars distalis. Maximum excitation is at 370–375 nm and maximum emission at 495–505 nm. The properties of the cellular fluorescence are indistinguishable from those of tryptamine or peptides with NH2-terminal tryptophan. From chemical analysis such peptides seem to occur abundantly in the mammalian pituitary. The concentration of these peptides agrees very well with the number and fluorescence intensity of the cells in all species studied. Furthermore, the tryptophyl peptides in the various parts of the pig pituitary have a distribution quite parallel to that of the fluorescent cells. As we have failed to detect tryptamine in the pituitary, we conclude that the formaldehyde-ozone-induced fluorescence in the adenohypophysis reflects the presence of tryptophyl peptides.This study was supported by grants from the Swedish Medical Research Council (04X-1007; 04X-3764), the Ford Foundation, Harald and Greta Jeanssons stiftelse and Riksföreningen mot Cancer (660-K73-01X).For brevity occasionally referred to as tryptophyl peptides. 相似文献
13.
Cells emitting orange-red autofluorescence have been found in the pars intermedia of aging rats. The fluorescence maximum of the emission is localized in an area of the spectrum where the most intense band maxima of porphyrins are located. The fluorescence fades when the excitation wavelength is about 400 nm, which is specific (Soret band) for the absorption spectra of porphyrins. The fluorescence is emitted by coarse inclusions in the cytoplasm of a few cells. These inclusions are also stainable with paraldehyde-fuchsin and exhibit a high endogenous peroxidase activity. The inclusions observed have morphologic features similar to those of porphyrin-containing astrocytes from the periventricular area of the hypothalamus. The inclusion-bearing cells of the pars intermedia also contain debris that might be due to the phagocytic activity of these cells. 相似文献
14.
This study considers the possible involvement of the tripeptide TRH (thyrotropin releasing hormone) in the physiological regulation of melanophore stimulating hormone (MSH) secretion from the pars intermedia of the toad, Xenopus laevis. TRH was shown to stimulate release of MSH from superfused neurointermediate lobes obtained from white-background adapted animals, but had no effect on secretion from lobes of black-background adapted animals. Immunohistochemical analysis revealed a rich TRH-containing neuronal network terminating in the neural lobe of the Xenopus pituitary. Plasma levels of TRH, determined with a specific radioimmunoassay, proved to be extremely high and no significant difference in this level could be found between white- and black-adapted animals. Plasma TRH probably originates from the skin, and our results show that its concentration is within the effective concentration range established for this peptide in stimulating MSH release from the pars intermedia. Therefore, while both our superfusion and immunohistochemical results argue favourably for a function of TRH in the regulation of MSH secretion, we conclude that, in any regulatory role, it would likely have to function within the pars intermedia at concentrations exceeding the high plasma values. While TRH could be involved in short-term activation of the secretory process in white-background adapted animals or in animals undergoing the initial stages of black background adaptation, our results indicate that this peptide may have no function in the maintenance of secretion from the pars intermedia of animals fully adapted to black background. 相似文献
15.
A A Ismail P G Saluja A J Thody J M Hamilton 《Zeitschrift für mikroskopisch-anatomische Forschung》1983,97(2):343-356
Long-term oestrogen treatment of male hamster induced renal carcinoma and pituitary enlargement due to hypertrophic and hyperplastic change in the pars intermedia. The latter effect was accompanied by ultrastructural abnormalities in pars intermedia cells and elevation of serum MSH concentration. Oestrogen treatment was stopped after 36 weeks and animals were killed at intervals from 8 to 36 weeks after oestrogen withdrawal. Nearly complete tumour regression occurred during the 36 weeks following cessation of oestrogen and by 28...36 weeks the pars intermedia cells regained normal ultrastructural appearance. However, pituitary enlargement and elevated serum MSH levels persisted throughout the post oestrogen recovery period. 相似文献
16.
Storage, secretion and subcellular localization of immunoreactive α -melanotropin (α -MSHi) and β -endorphin (β -ENDi) were examined in the pars intermedia of toads adapted to a black or white background. During white adaptation, there was a selective increase in storage of α -MSHi but not β -ENDi. Subcellular fractionation and release studies suggest the presence of two pools of peptides in the toad pars intermedia, each containing different molar ratios of α -MSHi and β -ENDi and regulated differently in their release. 相似文献
17.
An immunohistochemical study of adenohypophyseal cells in the viviparous reptile Chalcides chalcides 总被引:1,自引:0,他引:1
The morphology of the hypophysis and the immunocharacteristics of the adenohypophyseal cells in the viviparous reptile Chalcides chalcides were studied by light microscopy, using conventional staining methods and an indirect antibody technique (ABC method), respectively. The general morphology of the C. chalcides hypophysis was comparable to that of other reptiles, showing three main regions: the pars distalis, the pars intermedia and the pars nervosa. The gland appeared as an elongated body in a cephalic-caudal direction and was almost completely enclosed in the sella turcica. For this reason, the hypophysis was studied in toto with the brain in decalcified specimens. The pars distalis accounted for most of the whole organ. The pars intermedia surrounded the pars nervosa as a goblet. The pars tuberalis was lacking.The immunohistochemical identification of the adenohypophyseal cells was performed using rabbit antisera against mammalian/synthetic hypophyseal hormones. Prolactin cells were clustered in small cellular cordons in the rostral pars distalis and in the medial pars distalis in both male and female specimens. Somatotropic cells were found in the caudal pars distalis. Corticotropic cells were observed in the medio-rostral pars distalis, as well as in the pars intermedia, where melanotropic cells were also present. Melanotropic cells were confined to the pars intermedia. Gonadotropic cells were mostly distributed in the ventral and lateral portions of the pars distalis, where they were found isolated or in small clusters. Thyrotropic cells were detected in the pars distalis with a distribution similar to that of the gonadotropic cells; however, atypically, they were also found in the pars intermedia. Therefore, the cytological characteristics of the adenohypophyseal cells appeared mostly conserved. 相似文献
18.
Using the immunoperoxidase technique and specific antisera to synthetic ACTH beta (1-24), ACTH beta (17-39) and bMSHbeta1, selective immunocytochemical staining was localized in a distinctive cell type in the pars distalis and pars tuberalis of the dog pituitary gland. Except for a rare cell, the pars distalis and pars tuberalis did not stain with an anti-bMSH alpha serum. In the pars intermedia immunoreactive cells containing ACTH beta(1-24), ACTHbetap(17-39), bMSHbeta and/or bMSH alpha were observed. The specificity and validity of the antisera were demonstrated by elimination of their immunostaining capacity after prior absorption with their respective antigens, while absorption with other antigens failed to decrease staining intensity. The cytoplasm of the ACTH/MSH cells showed a positive reaction to periodic-acid-Schiff and assumed a pale aniline blue colour, whilst the granules were stained with carmoisine L and acid alizarine blue. These ACTH/MSH cells were further differentiated from other functional cell types of the pars distalis on the basis of their typical cytological features, intraglandular distribution and by immunochemical double staining. It is concluded that ACTH and MSH beta were present and most probably produced by the corticomelanotrophs of the pars distalis and pars tuberalis. In addition to corticomelanotrophs analogous to those of the pars distalis and pars tuberalis, the pars intermedia showed many cells which contain MSH alpha alone or together with MSH beta and/or ACTH. 相似文献
19.
C Bugnon D Lenys B Bloch D Fellmann 《Comptes rendus des séances de la Société de biologie et de ses filiales》1975,169(5):1271-1276
Formaldehyde-induced fluorescence, acid-catalyzed or not, methods, and immunocytology with anti-ACTH (1-24), anti-ACTH(17-39), ANTI-BETA-LPH immunserums were applied on the same preparations of cat, fox, rat and human foetus pituitaries. The superpositions of results showed that the pars intermedia and pars distalis corticomelano-lipotrophic cells of fox and cat pituitary, those of human foetal pituitary, and the purely corticotrophics cells of the rat pars distalis contained a fluorogenic probably granular compound. Moreover, the granules of the same cell types were electively revealed on our lymphilized material by plombic hematoxylin. Only the anti-beta-LPH and/or anti-beta-MSH fixing celpls exhibited hypercyanophilic, PAS-positive and bleu alcian-positive caracteristics. 相似文献
20.
The tannic acid-phosphomolybdic acid-amido black (TPA) stain has been used primarily for staining hemoglobin. That different dye lots of amido black cause variable staining is documented in the literature. Nine commercial samples of amido black were investigated using thin layer chromatography; all of these dyes contained colored contaminants. Separation of contaminants was achieved using silica gel thin layer chromatography and a solvent system of 95% ethanol:90% phenol:concentrated NH4OH, 12:9:3. TPA staining of red blood cells was improved by using purified amido black. 相似文献