GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    ORGAN CULTURE OF THE RAT ADRENAL MEDULLA: A MODEL SYSTEM FOR THE STUDY OF TRANS-SYNAPTIC ENZYME INDUCTION (1975)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 25 (1975), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: —It was the aim of the present study to develop organ culture conditions for the rat adrenal medulla which are representative for the in vivo situation. This is a prerequisite for studying the complex processes involved in trans-synaptic enzyme induction. The processes of trans-synaptic enzyme induction initiated in vivo by injecting 5 mg/kg of reserpine 2 h prior to the removal of the adrenal medulla, continued in this culture system and final levels of tyrosine hydroxylase were comparable to those seen in vivo. That these culture conditions are representative for the in vivo induction is also supported by the fact that transection of the splanchnic fibres supplying the adrenal medulla or administration of actinomycin D prior to reserpine abolished the rise in tyrosine hydroxylase activity not only in vivo, but also in culture.The findings that high concentrations (0·29 mm) of corticosterone in the culture medium inhibited the increase in tyrosine hydroxylase activity caused by reserpine support the hypothesis that glucocorticoids act as modulatory agents in trans-synaptic enzyme induction. This inhibition was exhibited only when corticosterone was added at the initiation of the culture period. If added 2 or 4 h after the beginning of the culture period there was little or no effect on the subsequent increase of tyrosine hydroxylase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1975.tb04340.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    EFFECT OF GLUCOCORTICOIDS ON NERVE GROWTH FACTOR-MEDIATED ENZYME INDUCTION IN ORGAN CULTURES OF RAT SYMPATHETIC GANGLIA: ENHANCED RESPONSE AND REDUCED TIME REQUIREMENT TO INITIATE ENZYME INDUCTION (1977)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 29 (1977), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract— After previous studies had shown that nerve growth factor produces a very similar change in the enzyme pattern of adrenergic neurons as does an increased activity of the preganglionic cholinergic nerves, the present experiments revealed that the nerve growth factor-mediated selective induction of TH and DBH is enhanced by glucocorticoids in a way similar to that mediated by acetylcholine via nicotinic receptors. Corticosterone (5 μM) produced not only an increase in the maximal response to NGF but shifted the concentration response curve of TH to NGF to the left. The potentiation effect was shown to be specific for glucocorticoids, since other steroid hormones like testosterone, β-estradiol and progesterone had no effect. Moreover, the glucocorticoid effect could be antagonized by cortexolone, suggesting an effect via glucocorticoid receptors. In addition to the potentiation of the nerve growth factor-mediated enzyme induction, glucocorticoids reduced the exposure time to NGF, necessary to initiate maximal TH induction, from 4 h to 10 min. The glucocorticoid potentiation of NGF-mediated specific enzyme induction is discussed in relation to the site and mechanism of action of NGF.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1977.tb03925.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    SYNTHESIS, SUBCELLULAR DISTRIBUTION AND TURNOVER OF DOPAMINE β-HYDROXYLASE IN ORGAN CULTURES OF SYMPATHETIC GANGLIA AND ADRENAL MEDULLAE (1976)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 27 (1976), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The synthesis, subcellular distribution and turnover of dopamine β-hydroxylase was studied in organ cultures of rat adrenal medullae and superior cervical ganglia. After exposure to [3H]leucine for 1 or 3 h, the tissues were homogenized at various time intervals and the amount of labelled dopamine β-hydroxylase in different subcellular fractions (cytosol, soluble and membrane-bound fraction of catecholamine storage vesicles) was determined by immunoprecipitation and subsequent electrophoresis. In cultured adrenal medullae, induction of dopamine β-hydroxylase initiated in vivo by administration of reserpine affected both soluble and membrane-bound pools of dopamine β-hydroxylase to a similar extent after pulse-labelling for 1 or 3 h. The half-lives of dopamine β-hydroxylase, which amounted to 6 h for the cytosol, 7.5 h for the soluble vesicular and 32 h for the membrane-bound vesicular pools were not altered by pretreatment with reserpine. In superior cervical ganglia the half-lives of the soluble pools were 2–3 times longer than in the adrenal medulla, whereas the half-life of the membrane-bound fraction was the same as in the adrenal medulla. In both organs the most heavily labelled fraction (both after a pulse of 1 or 3 h) was always that of the vesicular membrane, suggesting that newly-synthesized dopamine β-hydroxylase is immediately incorporated into the storage vesicles and not via release into the cytosol from the site of synthesis. The fact that the half-life of membrane-bound dopamine β-hydroxylase is markedly longer than that of the two soluble pools suggests that the single pools are not only independently supplied by newly-synthesized DBH but there is also no appreciable subsequent exchange between soluble and membrane-bound pools.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1976.tb00312.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    INCREASED SYNTHESIS OF DOPAMINE β-HYDROXYLASE IN CULTURED RAT ADRENAL EDULLAE AFTER IN VIVO ADMINISTRATION OF RESERPINE (1976)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 27 (1976), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract— The present experiments were designed to provide direct evidence that the increase in dopamine β-hydroxylase (DBH) activity after treatment with reserpme results from an augmented synthesis of new enzyme protein. After in vivo experiments had shown that DBH could not be labelled to a sufficient extent even after administration of high doses (8.3 mCi/kg) of [3H]leucine we took advantage of earlier observations that neuronally-mediated enzyme induction initiated in vivo progresses in organ cultures of adrenal medullae in a similar manner as in vivo. With that system it was possible to achieve a sufficient labelling of DBH molecules and to provide evidence that the increase in DBH activity produced by reserpine was really due to a specific increase in DBH synthesis. The fact that the half-life of DBH was identical in organ cultures of controls and reserpine-treated animals eliminated the possibility that the increased labelling of DBH after reserpine results from a slower rate of degradation.Both the experiments in vivo and in organ culture showed very clearly that the immunoprecipitation of labelled molecules has to be followed by additional purification by gel electrophoresis since in spite of the use of monospecific antibodies and careful washing of the immunoprecipitates contaminating coprecipitated labelled molecules accounted for up to 96% of the total precipitated radioactivity in whole adrenals (in vivo experiments) and up to 80% in adrenal medulla (organ culture experiments). The coprecipitation of contaminants most probably results from the addition of carrier proteins, used in order to make the precipitation of the small amounts of labelled proteins visible.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1976.tb01573.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Stimulation of the pituitary-adrenocortical axis by nerve growth factor (1979)
    [s.l.] : Nature Publishing Group
    Nature 282 (1979), S. 413-414 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] NGF was prepared from submaxillary glands of adult male mice by the method of Bocchini and Angeletti8, as the 2.5S subunit, with the modifications of Suda et al9. The purity of NGF was controlled by SDS gel electrophoresis and its biological activity was determined as described by Fenton10. The ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/282413a0
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Lack of correlation between changes in cyclic nucleotides and subsequent induction of tyrosine hydroxylase in rat adrenal medulla (1976)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 293 (1976), S. 105-108 
    Details
    ISSN: 1432-1912
    Keywords: cAMP/cGMP ratio ; Tyrosine hydroxylase induction ; Reserpine ; Dexamethasone ; Hypophysectomy ; Adrenal medulla
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Pretreatment of rats with dexamethasone (2.5 μmol/kg, a dose which blocks the release of ACTH from the pituitary gland) abolished the reserpine-mediated increase in cAMP and the increase in the cAMP/cGMP ratio in the adrenal medulla. In contrast, the reserpine-mediated induction of tyrosine hydroxylase (TH) remained unchanged. Hypophysectomy had a similar effect to dexamethasone treatment. Since changes in cAMP and changes in the cAMP/cGMP ratio are not indispensible prerequisites for the subsequent induction of TH, a causal relationship between the two phenomena seems to be excluded.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00498878
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Effect of hypophysectomy on cAMP changes in rat adrenal medulla evoked by catecholamines and carbamylcholine (1975)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 289 (1975), S. 157-170 
    Details
    ISSN: 1432-1912
    Keywords: Hypophysectomy ; cAMP ; Carbamylcholine ; Dopamine ; Adrenal Medulla ; Tyrosine Hydroxylase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary It was the aim of this study to investigate the mechanisms responsible for changes in 3′,5′-cyclic adenosine monophosphate (cAMP) in the rat adrenal medulla occuring after administration of carbamylcholine, histamine, ACTH and various phenylethylamines. Carbamylcholine, ACTH, histamine, noradrenaline and dopamine produced marked (500–900%) increases in adrenal cAMP which were very similar in both adrenal cortex and medulla both with respect to time-course and relative extent. Interestingly isoprenaline and adrenaline did not influence cAMP levels even at excessively high doses. In all cases studied transsection of the splanchnic fibers supplying the adrenals reduced the increase in medullary cAMP by not more than 25–30%, suggesting that cAMP levels in the adrenal medulla are predominantly regulated by non-neuronal mechanisms. This assumption was strongly supported by the observation that hypophysectomy completely abolished the 500–600% increase in cAMP produced by 50 μmol/kg of dopamine and reduced the 700% increase resulting from 4.4 μmol/kg of carbamylcholine to 70%. In spite of the marked increase in cAMP produced by single and repeated doses of dopamine in the adrenal medulla there was no subsequent induction of tyrosine hydroxylase (TH). Moreover carbamylcholine (8.2 μmol/kg) evoked TH induction only in innervated adrenals whereas after denervation, in spite of the large (+500%) and prolonged (more than 90 min) increase in cAMP, no TH induction could be observed. It is concluded that adrenal medullary cAMP is predominantly regulated by the pituitary gland via the adrenal cortex and only to a much smaller extent — if at all—by direct cholinergic mechanisms, which are responsible for the initiation of TH induction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00501303
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Mechanisms of tyrosine hydroxylase and dopamine β-hydroxylase induction in organ cultures of rat sympathetic ganglia by potassium depolarization and cholinomimetics (1976)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 292 (1976), S. 153-159 
    Details
    ISSN: 1432-1912
    Keywords: Potassium-depolarization ; Cholinomimetics ; Trans-synaptic induction ; Superior cervical ganglia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary It was the aim of the present study to elucidate the mechanisms involved in specific tyrosine hydroxylase (TH) and dopamine β-hydroxylase (DBH) induction by potassium depolarization and cholinomimetics in rat superior cervical ganglia kept in organ culture. The effect of high (54 mM) potassium concentration on intact ganglia seems to result in a dual action: a) a specific induction of TH and DBH via release of acetylcholine from preganglionic cholinergic nerve terminals. b) a non-specific effect on terminal adrenergic neurons resulting in a general increase of protein synthesis as indicated by the increase in DOPA decarboxylase (DDC) and monoamine oxidase (MAO) activities. In decentralized superior cervical ganglia potassium depolarization failed to produce the specific TH and DBH induction although a small increase in DDC activity persisted. Carbamylcholine, acetylcholine and nicotine at concentrations of 10−4 M elicited a selective induction of TH and DBH both in intact and decentralized ganglia via nicotinic receptor stimulation. Bethanechol, predominantly stimulating muscarinic receptors had no significant effect on TH activity. A 4 h pulse of 10−4 M carbamylcholine produced optimal induction of DBH and TH 24 h and 48 h later respectively. Longer exposure to carbamylcholine resulted in a significantly smaller rise in TH activity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00498586
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Short- and long-term effects of vinblastine on the rat adrenal medulla (1979)
    Springer
    Cell & tissue research 196 (1979), S. 271-287 
    Details
    ISSN: 1432-0878
    Keywords: Adrenal medulla (rat) ; Vinblastine ; Ultrastructure ; Catecholamines ; Enzymes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of a single high dose (10mg/kg) of vinblastine (vb) sulfate (“Velbe”, Lilly) on the ultrastructure, catecholamine (CA) content and activity of CA-synthesizing enzymes of the rat adrenal medulla were studied for up to 120h after intravenous injection of the drug. By 1 h, microtubules were virtually absent from chromaffin cells and preganglionic cholinergic axons, and typical paracrystals had appeared inside the nerve fibers. By 16h microtubules were completely reconstituted and paracrystals had disappeared. From 16h onwards, there was an increasing depletion of storage granules from adrenaline (A) — producing cells, which coincided with biochemical determinations showing a reduction of adrenal A to about 40 % of control levels by 48 h, with noradrenaline (NA) remaining in the range of controls. Both A- and NA-storing cells showed an extensive proliferation of the rough endoplasmic reticulum (ER). Vb caused a marked increase in tyrosine hydroxylase (TH; +113%) and dopamine β-hydroxylase (DBH; +82%) activities after 48 h. Splanchnicotomy completely abolished the vb-mediated increase in TH and DBH activities. A smaller increase (+ 47 %) in enzyme activity was observed with phenylethanolamine N-methyltransferase (PNMT). Vb (10−5M) had no apparent effect on granule content and the amount of rough ER in chromaffin cells, which were cultured for 48 h. The results demonstrate that a single high dose of vb has relatively little short-term effects on the rat adrenal medulla, but causes drastic long-term changes in CA-content and enzyme activities that are mediated by the preganglionic nerves. These changes could be interpreted as an effort to compensate for a loss of CA-stores in peripheral adrenergic nerves (cf. Cheney et al., 1973). The differential long-term effect of vb on adrenal NA and A might be due to the lower induction of PNMT as compared to TH and DBH activities and/or to a preferential release of A versus NA, which may occur at high frequencies of stimulation of the splanchnic nerves.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00240102
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...