scholarly journals CHANGES IN THE DNA CONTENT OF ADRENAL MEDULLA NUCLEI OF RATS INTERMITTENTLY EXPOSED TO COLD

1965 ◽  
Vol 25 (3) ◽  
pp. 415-433 ◽  
Author(s):  
Maria Pia Viola-Magni
Keyword(s):  
Aqueous Solutions ◽  
Adrenal Medulla ◽  
Dna Content ◽  
Functional Activity ◽  
Normal Values ◽  
Dry Mass ◽  
Considerable Decrease ◽  
Adult Rat ◽  
Before And After

In the adrenal medulla of rats exposed intermittently to cold (+4°C) for 100 and 300 hours, a considerable decrease (24 to 40 per cent) of the DNA content per nucleus was observed, followed by restoration to normal or above normal values within 10 days after the withdrawal of the stimulus. The findings were obtained with a scanning integrating histophotometer, and confirmed by microinterferometric investigations (on the basis of the measurement of total dry mass of nuclei isolated in aqueous medium before and after treatment with DNase) and by microchemical determinations, combined with the count of the nuclei in the homogenates. The observed decrease of DNA content cannot be attributed to errors of the methods used, nor to consequences of cellular degeneration. The available evidence seems to indicate a real decrease rather than a change in the state of a part of DNA in the nucleus in vivo whereby it becomes extractable by aqueous solutions. The restoration cannot be due to mitotic processes, which were actually never detected even with the use of colchicine, since the adrenal medulla cells in the adult rat are known to be irreversible, postmitotic cells. A correlation between the functional activity of the adrenal medulla cells and the content or state of DNA in their nuclei is demonstrated.

scholarly journals A RADIOAUTOGRAPHIC STUDY WITH H3-THYMIDINE ON ADRENAL MEDULLA NUCLEI OF RATS INTERMITTENTLY EXPOSED TO COLD

1966 ◽  
Vol 28 (1) ◽  
pp. 9-19 ◽  
Author(s):  
Maria Pia Viola-Magni
Keyword(s):  
Cell Division ◽  
Dna Synthesis ◽  
Adrenal Medulla ◽  
Cold Exposure ◽  
Dna Content ◽  
Room Temperature ◽  
Marked Variation ◽  
Considerable Decrease ◽  
The Third

A considerable decrease (24 to 40%) of DNA content per nucleus previously observed in the adrenal medulla of rats exposed intermittently to cold is followed by restoration to normal and supranormal values. This phenomenon has now been studied by use of H3-thymidine, which was given to normal rats, to rats exposed to cold, and to animals brought to room temperature after cold exposure. In the first two conditions, no significant labeling of nuclei was observed. In the third, labeling took place clearly in the 1st 3 days. The grain counts showed that the early labeled nuclei had more grains than those labeled later, indicating differences in the rate of DNA synthesis. A statistically significant correlation was found, on the same nuclei, between amount of Feulgen dye and number of grains. It is concluded that net synthesis of DNA takes place in the phase of recovery from cold. This fact is not related to cell division, as no mitoses could ever be detected, but rather to the cold-induced loss of DNA. Clear demonstration is thus given of a marked variation in the amount of DNA per nucleus in relation to the functional conditions of adrenal medulla cells.

scholarly journals Antiimmunosuppressive action of 3d-metal gluconates in experimental immunodeficiency

2018 ◽  
Vol 99 (2) ◽  
pp. 255-259 ◽  
Author(s):  
O A Knyazeva ◽  
S I Urazaeva ◽  
I G Konkina ◽  
L M Saptarova ◽  
L M Gazdalieva ◽  
...  
Keyword(s):  
Immunoglobulin G ◽  
Functional Activity ◽  
Test System ◽  
Classical Pathway ◽  
Zinc Gluconate ◽  
Sheep Erythrocytes ◽  
Immunodeficient Mice ◽  
Before And After

Aim. Evaluation of the effect of 3d-metal gluconates on complement-fixing function of immunoglobulin G and functional activity of complement. Methods. The study was conducted in vivo on 2.5-3 month-old white laboratory mice weighing 25-28 g with secondary immunodeficiency, which was induced by a single intraperitoneal injection of cyclophosphamide, as well as in vitro in a test system using sensitized sheep erythrocytes. Immunological studies were performed in intact animals, and before and after the administration of Mn, Co, Cu, and Zn gluconates to mice with induced immunodeficiency. The content of immunoglobulin G and its complexes with subcomponent of the complement first component C1q was determined in serum by ELISA using specific monoclonal antibodies. Results. Two-week oral administration of 3d-metal gluconates (Mn, Co, Cu, Zn) in a dose of 1/10 LD50 to immunodeficient mice was shown to cause a significant increase in the level of immunoglobulin G and its complexes with C1q. The greatest increase in concentration was observed with the introduction of zinc gluconate. Also by means of sensitized sheep erythrocytes in vitro, cobalt and, to a lesser extent, manganese gluconates were shown to increase the functional activity of C1q. Conclusion. 3d-metal gluconates (Mn, Co, Cu, Zn) demonstrate immunocorrecting properties: increase the content of immunoglobulin G and its complexes with C1q, significantly decreasing as a result of cyclophosphamide effect; cobalt and manganese gluconates have a stimulating effect on the functional activity of complement by its classical pathway, which indicates different mechanisms of immunocorrection action of studied metal gluconates and requires further studies.

ZUR FRAGE DER BIOSYNTHESE VON ALDOSTERON UND 11-DESOXYCORTICOSTERON IN DER NEBENNIERE UND IM ADENOM BEI EINEM PATIENTEN MIT PRIMÄREM ALDOSTERONISMUS

1969 ◽  
Vol 62 (3) ◽  
pp. 425-437 ◽  
Author(s):  
K. Dahm ◽  
H. Breuer ◽  
J. M. Bayer
Keyword(s):  
Urinary Excretion ◽  
Normal Values ◽  
Normal Range ◽  
Adrenal Tissue ◽  
Before And After ◽  
Normal Adrenal Tissue ◽  
Progesterone Metabolite ◽  
Very High

ABSTRACT In a 19-year old male patient, suffering from primary aldosteronism, the biosynthesis of 11-deoxycorticosterone and aldosterone was studied in slices of normal and adenomatous adrenal tissue; [4-14C] progesterone and [4-14C] 17α-hydroxyprogesterone were used as substrates. In addition, the urinary excretion of 1 1-deoxycorticosterone, tetrahydro-11-deoxycorticosterone and aldosterone was determined before and after operation. As compared with normal adrenal tissue, a very high activity of the 21-hydroxylase towards progesterone (metabolite: 11-deoxycorticosterone) as well as 17α-hydroxyprogesterone (metabolite: 17α-hydroxy-11-deoxycorticosterone) was found in the adenoma. In contrast, the activity of the 11β-hydroxylase was much less in the adenoma than in the normal adrenal tissue. In the absence of cofactors, only traces of aldosterone were detected in the experiments with slices of the adenoma, whereas a normal rate of production was observed in the experiments with the adrenal slices. The excretion of aldosterone in urine varied between 29.4 and 70.7 μg/24 h before operation; it was unaffected by dietetic measures, thus indicating an autonomy of the tumour. After operation, the concentration of aldosterone in urine fell to normal values (6.1–9.1 μg/24 h). The excretion of free 11-deoxycorticosterone (0.2–2.0 μg/24 h) and of its tetrahydroderivative (31.7–40.4 μg/24 h) was in the normal range before as well as after operation. The increased formation of 11-deoxycorticosterone and the decreased formation of aldosterone in the adenoma under in vitro conditions stand in contrast to the normal excretion of 11-deoxycorticosterone and the increased excretion of aldosterone in urine before operation. This discrepancy may be explained by the deficiency of cofactors in the slices of the adenoma. The results obtained support the view that, in steroid producing organs with high activities, only limited conclusions can be drawn from in vitro experiments to the situation in vivo.

scholarly journals I. QUANTITATIVE DETERMINATION OF THE AMOUNT OF DNA PER NUCLEUS BY INTERFERENCE MICROSCOPY

1969 ◽  
Vol 42 (2) ◽  
pp. 444-451 ◽  
Author(s):  
Cecilia Bibbiani ◽  
Roberto Tongiani ◽  
Maria Pia Viola-Magni
Keyword(s):  
Quantitative Determination ◽  
Dry Mass ◽  
Interference Microscopy ◽  
Isolated Nuclei ◽  
Adult Rat ◽  
Dnase Treatment ◽  
Dna Values ◽  
Before And After ◽  
Dna Complex

A method for the determination of the DNA content of isolated nuclei of different ploidy has been developed. It is based on measurement of the nuclear dry mass, with an integrating microinterferometer, before and after DNase treatment. The values found are slightly low, because, as indicated by biochemical determinations, consistently 5% to 8% of DNA is not extracted by DNase under these conditions. The average DNA values thus obtained for diploid and tetraploid nuclei of adult rat liver are 7.7 and 15.6 pg (10-12 g), respectively. Definite advantages of this procedure are: i) comparisons with biochemical determinations to give DNA values for each class of ploidy, ii) comparisons with histophotometry of the Feulgen dye-DNA complex to give absolute values instead of arbitrary units.

scholarly journals ANALYSIS OF ATTRIBUTION OF NOOPEPT TO SUBSTRATES AND MODULATORS OF FUNCTIONAL ACTIVITY OF ABCB1-PROTEIN IN IN VIVO EXPERIMENT

2017 ◽  
Vol 25 (1) ◽  
pp. 30-41
Author(s):  
I V. Chernykh ◽  
A V. Shchulkin ◽  
E N. Yakusheva ◽  
M V. Gatsanoga ◽  
N M. Popova
Keyword(s):  
Functional Activity ◽  
Hplc Method ◽  
Transport Protein ◽  
Pharmacokinetic Parameters ◽  
Protein Marker ◽  
Protein Substrates ◽  
Before And After ◽  
The Given ◽  
Abcb1 Protein

In the article the influence of nootropic drug Noopept (N-phenyl-acetyl-L-prolylglycine ethyl ester) on the functional activity of ABCB1-protein is analyzed and attribution of this drug to the transport protein substrates is studied on male Chinchilla rabbits. Functioning of the transport protein was estimated by the pharmacokinetics of its marker substrate - fexofenadine. Fexofenadine was introduced intragastrically one time in the dose 67,5 mg/kg b.w. before and after 14-day introduction of Noopept in the dose 10 mg/kg b.w. 3 times a day. The quantity of the substance was determined by HPLC method according to the previously developed procedure.Belonging of Noopept to ABCB1-protein substrates was estimated by comparison of its pharmacokinetic parameters before and after a course of introduction of verapamil (the known inhibitor of the ABCB1-protein) into male rabbits in the dose 20 mg/kg b.w. 3 times a day. The pharmacokinetics of Noopept was studied by the original HPLC method.It was found that the course of Noopept introduction did not lead to any reliable changes in the pharmacokinetic parameters of the ABCB1-protein marker substrate - fexofenadine, which may evidence preservation of the functional activity of the given transport protein at the initial level. It was also found that the pharmacokinetics of Noopept remained unchanged after a course of introduction of ABCB1-protein inhibitor - verapamil - in to the male rabbits, that is, Noopept is not a substrate of the given transport protein.

The Action of Juvenile Hormone on the Follicle Cells of Rhodnius Prolixus: the Importance of Volume Changes

1977 ◽  
Vol 69 (1) ◽  
pp. 33-44 ◽  
Author(s):  
RANDA ABU-HAKIMA ◽  
K. G. DAVEY
Keyword(s):  
National Research Council ◽  
Dry Mass ◽  
Rhodnius Prolixus ◽  
Interference Microscopy ◽  
Follicle Cells ◽  
Volume Changes ◽  
Cross Sectional ◽  
Original Volume ◽  
Before And After

1. The onset of vitellogenesis in Rhodnius prolixus is marked by a reduction in the height of the follicle cells. This decrease is not observed in follicle cells from allatectomized females. Estimates of the changes in cross-sectional area of the cells suggest that the cells shrink to about 50% of their original volume as the result of JH action. 2. Determination by interference microscopy of the volume of isolated living follicle cells before and after exposure to JH also suggest that the volume is reduced to 50 % of the original volume as a result of JH action. There was no decrease in volume of follicle cells from allatectomized females following exposure to JH. 3. During mid to late vitellogenesis in vivo, an increase in cell volume was measured, an increase that possibly reflects an increase in cellular dry mass. 4. It is concluded that follicle cells normally respond to JH by pumping out fluid, thus reducing their volume, and leading to the development of spaces between the cells. Note: This work is supported by the National Research Council of Canada

Effects of Ca2+ channel antagonists on acetylcholine and catecholamine releases in the in vivo rat adrenal medulla

2004 ◽  
Vol 287 (1) ◽  
pp. R161-R166 ◽  
Author(s):  
Tsuyoshi Akiyama ◽  
Toji Yamazaki ◽  
Hidezo Mori ◽  
Kenji Sunagawa
Keyword(s):  
Adrenal Medulla ◽  
Nerve Stimulation ◽  
Chromaffin Cells ◽  
Splanchnic Nerve ◽  
Ringer Solution ◽  
Norepinephrine Release ◽  
Ach Release ◽  
Before And After ◽  
Voltage Dependent

To elucidate the types of voltage-dependent Ca2+ channels controlling ACh and catecholamine releases in the in vivo adrenal medulla, we implanted microdialysis probes in the left adrenal medulla of anesthetized rats and investigated the effects of Ca2+ channel antagonists on ACh, norepinephrine, and epinephrine releases induced by nerve stimulation. The dialysis probes were perfused with Ringer solution containing a cholinesterase inhibitor, neostigmine. The left splanchnic nerves were electrically stimulated at 2 and 4 Hz before and after intravenous administration of Ca2+ channel antagonists. ω-Conotoxin GVIA (an N-type Ca2+ channel antagonist, 10 μg/kg) inhibited ACh release at 2 and 4 Hz by ∼40%, norepinephrine release at 4 Hz by ∼50%, and epinephrine release at 2 and 4 Hz by ∼45%. A fivefold higher dose of ω-conotoxin GVIA (50 μg/kg) did not further inhibit these releases. ω-Conotoxin MVIIC (a P/Q-type Ca2+ channel antagonist, 50 μg/kg) inhibited ACh and epinephrine releases at 4 Hz by ∼30%. Combined ω-conotoxin GVIA (50 μg/kg) and MVIIC (250 μg/kg) inhibited ACh release at 2 and 4 Hz by ∼70% and norepinephrine and epinephrine releases at 2 and 4 Hz by ∼80%. Nifedipine (an L-type Ca2+ channel antagonist, 300 and 900 μg/kg) did not change ACh release at 2 and 4 Hz; however, nifedipine (300 μg/kg) inhibited epinephrine release at 4 Hz by 20%, and nifedipine (900 μg/kg) inhibited norepinephrine and epinephrine releases at 4 Hz by 30%. In conclusion, both N- and P/Q-type Ca2+ channels control ACh release on preganglionic splanchnic nerve endings while L-type Ca2+ channels do not. L-type Ca2+ channels are involved in norepinephrine and epinephrine releases on chromaffin cells.

Radiolabeled r-Hirudin as a Measure of Thrombin Activity at, or within, the Rabbit Aorta Wall In Vitro and In Vivo

1994 ◽  
Vol 71 (04) ◽  
pp. 499-506 ◽  
Author(s):  
Mark W C Hatton ◽  
Bonnie Ross-Ouellet
Keyword(s):  
Rabbit Aorta ◽  
Balloon Injury ◽  
Recombinant Hirudin ◽  
Aorta Wall ◽  
Thrombin Activity ◽  
Before And After ◽  
The Matrix

SummaryThe behavior of 125I-labeled recombinant hirudin towards the uninjured and de-endothelialized rabbit aorta wall has been studied in vitro and in vivo to determine its usefulness as an indicator of thrombin activity associated with the aorta wall. Thrombin adsorbed to either sulfopropyl-Sephadex or heparin-Sepharose bound >95% of 125I-r-hirudin and the complex remained bound to the matrix. Binding of 125I-r-hirudin to the exposed aorta subendothelium (intima-media) in vitro was increased substantially if the tissue was pre-treated with thrombin; the quantity of l25I-r-hirudin bound to the de-endothelialized intima-media (i.e. balloon-injured in vitro) correlated positively with the quantity of bound 131I-thrombin (p <0.01). Aortas balloon-injured in vivo were measured for thrombin release from, and binding of 125I-r-hirudin to, the de-endothelialized intimal surface in vitro; 125I-r-hirudin binding correlated with the amount of active thrombin released (p <0.001). Uptake of 125I-r-hirudin by the aorta wall in vivo was proportional to the uptake of 131I-fibrinogen (as an indicator of thrombin activity) before and after balloon injury. After 30 min in the circulation, specific 125I-r-hirudin binding to the uninjured and de-endo- thelialized (at 1.5 h after injury) aorta wall was equivalent to 3.4 (± 2.5) and 25.6 (±18.1) fmol of thrombin/cm2 of intima-media, respectively. Possibly, only hirudin-accessible, glycosaminoglycan-bound thrombin is measured in this way.

The Effect of Active Site-inhibited Factor VIIa on Tissue Factor-initiated Coagulation Using Platelets before and after Aspirin Administration

1997 ◽  
Vol 78 (04) ◽  
pp. 1202-1208 ◽  
Author(s):  
Marianne Kjalke ◽  
Julie A Oliver ◽  
Dougald M Monroe ◽  
Maureane Hoffman ◽  
Mirella Ezban ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Active Site ◽  
Large Scale ◽  
Thrombin Generation ◽  
Factor Viia ◽  
Dependent Manner ◽  
Antithrombotic Agent ◽  
Before And After ◽  
Ic50 Values

SummaryActive site-inactivated factor VIIa has potential as an antithrombotic agent. The effects of D-Phe-L-Phe-L-Arg-chloromethyl ketone-treated factor VIla (FFR-FVIIa) were evaluated in a cell-based system mimicking in vivo initiation of coagulation. FFR-FVIIa inhibited platelet activation (as measured by expression of P-selectin) and subsequent large-scale thrombin generation in a dose-dependent manner with IC50 values of 1.4 ± 0.8 nM (n = 8) and 0.9 ± 0.7 nM (n = 7), respectively. Kd for factor VIIa binding to monocytes ki for FFR-FVIIa competing with factor VIIa were similar (11.4 ± 0.8 pM and 10.6 ± 1.1 pM, respectively), showing that FFR-FVIIa binds to tissue factor in the tenase complex with the same affinity as factor VIIa. Using platelets from volunteers before and after ingestion of aspirin (1.3 g), there were no significant differences in the IC50 values of FFR-FVIIa [after aspirin ingestion, the IC50 values were 1.7 ± 0.9 nM (n = 8) for P-selectin expression, p = 0.37, and 1.4 ± 1.3 nM (n = 7) for thrombin generation, p = 0.38]. This shows that aspirin treatment of platelets does not influence the inhibition of tissue factor-initiated coagulation by FFR-FVIIa, probably because thrombin activation of platelets is not entirely dependent upon expression of thromboxane A2.

Determination and Treatment of Disorders of Primary Haemostasis

1999 ◽  
Vol 19 (04) ◽  
pp. 168-175 ◽  
Author(s):  
M. Weippert-Kretschmer ◽  
V. Kretschmer
Keyword(s):  
Platelet Function ◽  
Bleeding Risk ◽  
Bleeding Complications ◽  
Bleeding Tendency ◽  
Platelet Counts ◽  
Platelet Function Disorders ◽  
Perioperative Bleeding ◽  
Before And After ◽  
Low Sensitivity

SummaryPerioperative bleeding complications due to disorders of primary haemostasis are often underestimated. Routine determination of primary haemostasis is still problematic. The in vivo bleeding time (BT) shows low sensitivity and high variability. In this contribution the results and experiences with the IVBT having been obtained in various studies and during 10 years of routine use are reported. Patients and Methods: Blood donors before and after ASA ingestion, patients with thrombocytopenia as well as congenital and acquired platelet function disorders. Monitoring of desmopressin efficacy. IVBT with Thrombostat 4000 (tests with CaCl2 = TST-CaCl2 and ADP = TST-ADP) and PFA-100 (test cartridges with epinephrine = PFA-EPI and ADP = PFA-ADP). Results and Conclusions: IVBT becomes abnormal with platelet counts <100,000/μl. With platelet counts <50,000/μl the results are mostly outside the methodical range. IVBT proved clearly superior to BT in von Willebrand syndrome (vWS). All 16 patients with vWS were detected by PFA-EPI, whereas with BT 7 of 10 patients with moderate and 1 of 6 patients with mild forms of vWS were spotted. The majority of acquired and congenital platelet function disorders with relevant bleeding tendency were detectable by IVBT. Sometimes diagnostic problems arose in case of storage pool defect. Four to 12 h after ingestion of a single dose of 100 mg ASA the TST-CaCl2 became abnormal in all cases, the PFA-EPI only in 80%. However, the ASA sensitivity of TST-CaCl2 proved even too high when looking for perioperative bleeding complications in an urological study. Therefore, the lower ASS sensitivity of the PFA-100 seems to be rather advantageous for the estimation of a real bleeding risk. The good efficacy of desmopressin in the majority of cases with mild thrombocytopenia, congenital and acquired platelet function disorders and even ASS-induced platelet dysfunction could be proven by means of the IVBT. Thus IVBT may help to increase the reliability of the therapy. However, the IVBT with the PFA-100 is not yet fully developed. Nevertheless, routine use can be recommended when special methodical guidelines are followed.

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