Library

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
    Elevation of γ-Aminobutyric Acid in Cultured Rat C6 Glioma Cells Following Methionine Supplementation (1980)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 34 (1980), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1980.tb11281.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    COMPARATIVE AND REGIONAL DIFFERENCES IN SEROTONIN CONTENT OF REPTILIAN BRAINS (1964)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 11 (1964), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1964.tb06729.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    PRODUCT INHIBITION OF RAT BRAIN HISTAMINE-N-METHYLTRANSFERASE (1978)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 30 (1978), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract— The inhibition of S-adenosylmenthionine: histamine-N-methyltransferase (EC 2.1.1.8; HMT) by its products, 3-methylhistamine (3-MetHm) and S-adenosyl-l-homocysteine (SAH), was examined using a preparation of the enzyme which was partially purified from rat brains. SAH was found in in vitro experiments, to be a competative inhibitor of HMT in relation to S-adenosyl-l-methionine (SAM), with a Ki= 5.6 μM. SAH was shown to be a non-competitive inhibitor with respect to histamine (Hm) (Ki= 5.0 μM). The Km's for SAM and Hm were 10.2 and 3.0 μM respectively. On the other hand, 3-MetHm was determined to be a non-competitive inhibitor of HMT with respect to Hm (Ki= 8.7 μM) and an uncompetitive inhibitor with respect to SAM (Ki= 9.6 μM). These results suggest that the addition of the substrate to, and the release of products by, HMT occurs sequentially. In the nomenclature Of Cleland (1963) the reaction is seemingly of the ‘ordered Bi-Bi’ type.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1978.tb10490.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Quantitative Cytological Analysis of Functional Changes in Adrenomedullary Chromaffin Cells in Normal, Sham-Operated, and Pinealectomized Rats in Relation to Time-of-day: II. Nuclear-Cytoplasmic Ratio, Nuclear Size, and Pars Granulosa of Nucleolus (1988)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of pineal research 5 (1988), S. 0 
    Details
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Adrenaline(A)- and noradrenaline(N)-cells in the adrenal medulla of nonoperated (NO), sham-operated (SO), and pinealectomized (PX) male rats (n = 125) were investigated by quantitative electron and light microscopy. Animals were killed at eight time points during a standardized 24-h, light-dark (12:12) cycle 14 days after surgery. Nuclear-cytoplasmic (N/P) ratios, diameters of nuclei, and the frequency of nucleoli showing a large amount of pars granulosa (granulated nucleoli), were the primary characteristics studied.Major findings include the following: 1) The frequency of low N/P ratios over a 24-h period tended to be higher in PX animals than in controls in A-cells, as shown in large cell profiles (P 〈 0.02); but such a tendency was not apparent in N-cells. Daily mean nuclear diameters were similar among the three experimental groups. 2) The 24-h changing pattern of phase relations in the frequency of low N/P ratio and nuclear size differed between A- and N-cells in NO and SO but not in PX animals. 3) The frequency of granulated nucleoli in A-cells was much higher in PX animals than in NO and SO animals throughout a 24-h period (P 〈 0.018), especially from the late light to early dark phase (P 〈 0.003), and higher in A-cells than in N-cells generally (P 〈 0.0009). Pinealectomy thus caused increases in the cytoplasm and in the pars granulosa of the nucleolus in many A-cells; changes in N-cells were less apparent. This suggest a disturbed balance and coordination between A- and N-cell systems of adrenal medulla following pinealectomy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-079X.1988.tb00778.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Increases in Volume, Fluid Content, and Lens Weight of Eyes Following Systemic Administration of Melatonin (1984)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of pineal research 1 (1984), S. 0 
    Details
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Melatonin's effects were studied in male golden hamsters (Mesocricetus auratus) distributed among five surgical groups (nonoperated, sham-pinealectomized, sham-pinealectomized plus black plastic shielding of the pineal region, pinealectomized, and pinealectomized plus black plastic shielding of the pineal region) and three injection groups (vehicle only, 25 μg melatonin, and 2,500 μg melatonin). Injections (s.c.) were daily for 28 d at L11 to L11.75 in a (light:dark) L:D 14:10 artificial photoperiod. Animals (N = 112) were killed and dissected on the day after the last injection (at 55–65 d of age). None of rhe surgical procedures affected weights of eyes or their parts, nor did they influence the effects of administered melatonin on the eyes. Melatonin caused an increase in absolute and relative eye weight and an increase in fluid content of intraocular space. The magnitudes of these effects were positively related to melatonin dose. These same eyes had a progressively lower weight of nonlenticular tissues with low to high doses of melatonin, probably in relation to greater fluid content, and suspected increase in intraocular pressure. Lens wet and dry weights were significantly greater in animals receiving melatonin, but only at the high dose. These actions of melatonin are likely to be direct and are shown to not require the presence of the pineal. Experiments of other designs are suggested in order to determine whether the effects of the low, near physiological, dose of melatonin represent physiological actions of endogenous melatonin, synthesized and released within the eye. However, effects of large doses of melatonin on the eye are still noteworthy in relation to interpretation of experiments employing such dosages, and of disease states involving changes in intraocular pressure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-079X.1984.tb00190.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Quantitative Cytological Analysis of Functional Changes in Adrenomedullary Chromaffin Cells in Normal, Sham-Operated, and Pinealectomized Rats in Relation to Time of Day: III. Nuclear Density (1988)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of pineal research 5 (1988), S. 0 
    Details
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The sizes of adrenaline (A) and noradrenaline (N) cells in the adrenal medulla of nonoperated (NO), sham-operated (SPX), and pinealectomized (PX) male rats (n = 126) were investigated by quantitative light microscopy. Animals were killed at eight time points during a standardized 24-h, light-dark (12:12) cycle 14 days after surgery. Nuclear densities were measured in semithin sections of eponembedded specimens, initially fixed with glutaraldehyde and OsO4. Major findings are as follows. 1) The mean size of adrenomedullary A cells throughout 24 h (P〈0.001), especially in the dark phase (P〈0.001) but not in the light phase, was larger in PX animals than in NO and SPX animals. There were no statistically significant differences in the size of N cells among the three experimental groups in either the dark phase or the light phase. 2) The sizes of A and N cells showed time-of-day changes in the NO and the SPX animals but not in the PX animals. The temporal relationship of 24-h changes in the cell size tended to be different between A and N cells in the NO and the SPX animals but not in the PX animals. 3) The cell size was apparently larger in A cells than in N cells in each experimental group. Pinealectomy thus caused hypertrophy of A cells, especially in the dark phase, but not apparently hypertrophy of N cells. Concerning the pinealectomy effects in relation to the time of day, the results support the hypothesis of pineal action being phase-tuning and coordinating of at least some circadian systems.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-079X.1988.tb00795.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Effects of Pinealectomy on the Mitotic Activity of Adrenomedullary Chromaffin Cells in Relation to Time of Day (1990)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of pineal research 8 (1990), S. 0 
    Details
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The frequency of mitoses of adrenaline (A) cells and noradrenaline (N) cells in the adrenal medulla of nonoperated (NO), sham-operated (SPX), and pinealectomized (PX) male, 53-day-old Holtzman rats (n = 133) was investigated by means of light microscopy. Animals were killed at eight time points during a standardized 24-h light-dark (12:12) cycle 14 days after surgery. Mitotic indices (n/1,000) were determined in sections of adrenal medulla fixed with glutaraldehyde and OsO4. Overall frequency of mitoses was extremely low (mitotic index: 0.73 = 115/157,223). Daily mean mitotic index was maximum in A cells (0.83) and minimum in N cells (0.52) of PX group but did not show statistically significant differences between cell types or experimental groups. Neither cell type in NO animals showed 24-h changes in mitotic index, but cells in SPX animals did, with highest value in the late dark phase and lowest in the late light phase, when values of two cell types were combined (P〈0.01–0.001). In PX animals, mitotic index followed a similar but more distinct 24-h change in A cells (P〈0.009), but not in N cells, resulting in different time-of-day changes between two types of cells (P〈0.01–0.05). The mitotic index was higher in PX than in control (NO and SPX) animals in the middark phase (P〈0.05) and lower in operated (SPX and PX) than in nonoperated (NO) animals from late light to the early dark phase, suggesting that the latter was possibly due to a residual effect of the surgery. These results are consistent with the interpretation that the pineal has an inhibitory action on A cells and may coordinate the two types of cells in their mitotic activity, especially in the middark phase of the daily cycle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-079X.1990.tb00803.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Quantitative Ultrastructural Analysis of Differences in Exocytosis Number in Adrenomedullary Adrenaline Cells of Golden Hamsters Related to Time of Day, Pinealectomy, and Intracellular Region (1985)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of pineal research 2 (1985), S. 0 
    Details
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: This research analyzed differences mainly in the incidence of exocytotic figures in adrenaline cells (A - cells) in pinealectomized (PX), sham-operated (SPX), and non-operated (NO) adult male golden hamsters, with the aim of determining whether these parameters change with the time of day and following pinealectomy, and whether intracellular regional differences exist in such changes. Animals acclimated to a standardized light: dark (LD) 12:12 photoperiod were sacrificed at 11 h after the onset of light (L-11h) and 1 h after the onset of darkness (D-1h) (8 animals/group/time) at 28 days postoperation. The adrenal medullas were examined and analyzed morphometrically by electron microscopy. The number of exocytoses per unit length (NEL) and the exocytosis index (a rough index of the number of exocytoses per cell) were measured in PF (perivascular-space-facing) and non-PF plasma membranes. NEL increased from L-11h (NO: 0.040 ± 0.010, X̄± SE) to D-1h (0.078 ± 0.012) in all three experimental groups (ANOVA: P 〈 0.005), showing over fourfold higher levels in PF than in non-PF membranes. NEL in PF membranes in PX animals showed higher levels than those in NO and SPX animals (P 〈 0.025), but in non-PF membranes, no differences owing to time of day or surgery were seen. Exocytosis indices were (1) higher at D-lh than at L-llh in all three experimental groups (P 〈 0.005), (2) similar in PF and non-PF membranes in control groups, and (3) higher in PF membranes in the PX group than in either non-PF membranes or PF membranes in control groups. In conclusion, the exocytosis number in A cells changes in relation to time of day, rising in early dark phase, and its rise following pinealectomy can be seen only in PF membranes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-079X.1985.tb00644.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Effects of Melatonin on Adrenomedullary Dopamine-β-Hydroxylase Activity in Golden Hamsters: Evidence for Pineal and Dose Dependencies (1986)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of pineal research 3 (1986), S. 0 
    Details
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Pineal influence in the control of adrenomedullary function in golden hamsters was investigated by examining changes in adrenal dopamine-β-hydroxylase (DBH) activity following pinealectomy, either alone or in combination with melatonin administration. Adult males acclimated to an LD 14:10 photoperiod were distributed in five experimental groups: intact controls (NO), sham-pinealectomized (S), sham-pinealectomized with black plastic shielding of the pineal region, pinealectomized (PX), and pinealectomized with the operated region shielded. Animals representing all of these groups were injected (between L11 and L11.75) with either vehicle, or a low dose (25 μg) or a high dose (2,500 μg) of melatonin daily for 28 days, after which they were killed, and the adrenals were collected for assay of DBH activity by means of a sensitive radioenzymatic method. We found that (1) PX + vehicle led to increased (P 〈.05) adrenal DBH activity in comparison with either NO or S groups; (2) daily 25 μg of melatonin resulted in lowered DBH activity in the NO group when compared with NO + vehicle (P 〈.001) or S + vehicle (P 〈.001) groups; (3) PX + 25 μ melatonin reversed the action of 25 μg melatonin in the NO + 25 μg group; (4) 2,500 μg melatonin was without effect on adrenal DBH in any of the injected surgical groups. These results show an inhibitory pineal influence on adrenal DBH activity, and that this was dose dependent. Furthermore, the inhibitory effect of exogenous melatonin on adrenomedullary DBH activity depended upon the presence of the pineal, suggesting a mediating role of the pineal in this particular action of melatonin. Since DBH catalyzes dopamine conversion to norepinephrine, a hormone and hormone precursor of the adrenal medulla, these results demonstrate, within at least one time frame, an inhibitory action of the pineal and melatonin on adrenomedullary catecholaminergic function.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-079X.1986.tb00762.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Effects of Melatonin Implants on Structures and Behaviors of the House Finch (Carpodacus mexicanus) Eye (1986)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of pineal research 3 (1986), S. 0 
    Details
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: This study aimed to determine the extraretinal effects of melatonin upon the eyes of an avian species, the House Finch (Carpodacus mexicanus). Twelve birds (full-grown, second-year males) each received a Silastic tubing intraperitoneal implant, six containing melatonin (average release = 24μg/d/bird; = M birds) and six being empty (= C birds). Microscopic study of pupillary and palpebral behaviors during the final week demonstrated lesser pupillary diameters and interpalpebral distances in M birds under all test conditions. These effects could have diminished mean light levels reaching parts of the retina. Characteristics of the relative miosis and ptosis of M birds resemble signs in some CNS disorders, such as altered inhibition of the Edinger-Westphal nucleus, and especially lesions in, or lowered activity of, higher sympathetic centers (a subtype of Horner's syndrome). Weights of eyes and their parts were the same in M and C birds, contrasting with previously reported results from male Golden Hamsters, possibly due to species differences and/or preexperimental attainment of full growth in the finches. Effects of melatonin on pupillary and palpebral behaviors, demonstrated here for the first time, foster caveats for simplistic experimental designs and interpretations with melatonin when sensory-neural-behavioral interactions are affected. Quantitative changes in pupillary and palpebral behaviors may, nevertheless, provide a window for monitoring central actions of melatonin in living test subjects in chronic studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-079X.1986.tb00737.x
    Library Location Call Number Volume/Issue/Year 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...