scholarly journals The effects of oestradiol on nucleoside transport in rat uterus

1971 ◽  
Vol 121 (1) ◽  
pp. 83-88 ◽  
Author(s):  
Janet M. Oliver
Keyword(s):  
Cytosine Arabinoside ◽  
Concentration Gradient ◽  
Initial Rate ◽  
Nucleoside Transport ◽  
Facilitated Diffusion ◽  
Rat Uterus ◽  
Intracellular Space ◽  
Uridine Uptake

1. By using the non-metabolized cytidine analogue, cytosine arabinoside, it was possible to examine the mechanism of nucleoside transport in the immature rat uterus in the absence of intracellular utilization of the permeant. It was demonstrated that the uptake of cytosine arabinoside is not accumulative and that it can be competitively inhibited by the addition of a second nucleoside, uridine. Introduction of a concentration gradient of uridine from the medium towards the intracellular water promotes the counterflow of cytosine arabinoside out of the cells against its concentration gradient. These properties indicate that a facilitated-diffusion system is involved in nucleoside transport in the uterus. Further counterflow studies have shown that the transport system has a broad specificity for purine and pyrimidine nucleosides and that it is distinct from the processes that mediate the uptake of sugars, amino acids and purine and pyrimidine bases. 2. Oestradiol injection has no effect on the initial rate of cytosine arabinoside uptake in vitro. The increased amount of the analogue taken up per uterus is simply due to the expansion of the uterine volume that accompanies oestrogen action. 3. It is concluded that the striking increase in uridine uptake, observed in vivo in uteri from oestrogen-treated rats, does not result from an increase in the initial rate of nucleoside transport into the intracellular space of the tissue.

o,p′-DDT (1,1,1-trichloro-2 (p-chlorophenyl) 2-(o-chlorophenyl) ethane is a purely estrogenic agonist in the rat uterus in vivo and in vitro

1987 ◽  
Vol 36 (3) ◽  
pp. 397-400 ◽  
Author(s):  
Paul Galand ◽  
Nicole Mairesse ◽  
Chantal Degraef ◽  
Jacques Rooryck
Keyword(s):  
Rat Uterus

scholarly journals Two classes of murine granulocyte progenitor cells expressed in plasma clot diffusion chamber cultures

Blood ◽  
1982 ◽  
Vol 59 (4) ◽  
pp. 838-843 ◽  
Author(s):  
HN Steinberg ◽  
PL Page ◽  
SH Robinson
Keyword(s):  
Bone Marrow ◽  
Progenitor Cells ◽  
Cytosine Arabinoside ◽  
Diffusion Chamber ◽  
Velocity Sedimentation ◽  
Mouse Bone Marrow ◽  
Plasma Clot ◽  
Residual Concentration

Abstract Two distinct classes of granulocyte progenitor cells present in normal mouse bone marrow are expressed sequentially in the vivo plasma clot diffusion chamber culture system. By several criteria, progenitor cells giving rise to granulocyte colonies on day 4 of culture (CFU-D4) are different from those giving rise to colonies on day 7 (CFU-D7). These differences include: cell cycle activity as measured by in vitro incubation with cytosine arabinoside, residual concentration in the bone marrow after in vivo treatment of donor mice with cytosine arabinoside or methotrexate, resistance to osmotic lysis, size as determined by velocity sedimentation, and the morphology of the granulocyte colonies to which these cells give rise. The CFU-D7 appears to represent an earlier progenitor cell than the CFU-D4 in the differentiation pathway of the granulocyte and is analagous in many respects to the BFU-E in the erythroid pathway.

scholarly journals Covalent crosslinking of von Willebrand factor to fibrin

Blood ◽  
1986 ◽  
Vol 68 (1) ◽  
pp. 95-101 ◽  
Author(s):  
M Hada ◽  
M Kaminski ◽  
P Bockenstedt ◽  
J McDonagh
Keyword(s):  
Von Willebrand Factor ◽  
Initial Rate ◽  
Factor Xiiia ◽  
Covalent Bonds ◽  
Covalent Crosslinking ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Plasmin Inhibitor

Abstract Factor XIIIa crosslinks a limited number of substrates via epsilon(gamma-glutamyl)-lysyl bond formation. It crosslinks fibrin to itself, alpha 2-plasmin inhibitor and fibronectin to fibrin, and fibronectin to collagen. Results presented here show that plasma von Willebrand factor (vWF) is a substrate for factor XIIIa and can be crosslinked to fibrin during gel formation. vWF-fibrin crosslinking was studied in purified systems and in plasma with 125I-vWF and 131I- fibrinogen. vWF incorporation into fibrin increased with time or increasing factor XIIIa. After electrophoresis of dissolved clots, distribution of 125I and 131I was measured and showed that vWF was crosslinked to the alpha chain of fibrin and entered the high-mol-wt alpha polymer. vWF-fibrin crosslinking decreased the initial rate of alpha polymer formation. Crosslinking of vWF polymer to itself could not be demonstrated under physiologic conditions but occurred if vWF was reduced first. Factor XIIIa catalyzed incorporation of putrescine into both monomeric and polymeric vWF. Altogether, these studies indicate that factor XIIIa can readily form covalent bonds between glutamine in vWF and lysine in fibrin alpha chains. This reaction occurs readily in vitro when plasma clotting is slow and may occur in vivo under similar conditions.

scholarly journals Interaction of nistranol with estradiol and progesterone receptors in the rat uterus cytosol in vitro and in vivo

1996 ◽  
Vol 42 (4) ◽  
pp. 33-34
Author(s):  
Ye. N. Kareva ◽  
V. P. Fedotov ◽  
V. M. Rzheznikov ◽  
Ye. V. Solovyova ◽  
Ye. V. Pokrovskaya
Keyword(s):  
Single Injection ◽  
Progesterone Receptors ◽  
Uterine Tissue ◽  
Rat Uterus ◽  
Cytosol Fraction ◽  
Receptor Complexes ◽  
Target Organs ◽  
Uterine Growth

Interactions between nistranol and estradiol and progesterone receptors in the cytosol fraction of the uterine tissue of oophorectomized rats and the relative competitive capacity of nistranol have been studied 24 h after a single injection of the drug. The results demonstrate the effects of nistranol on estradiol and progesterone binding. Nistranol boosting of uterine growth in rats is explained by its capacity to accelerate the translocation of hor- mone-receptor complexes into the nucleus. Investigations of the capacity of new estrogens to compete with estradiol for binding in the tissues of target organs in vitro and affect estradiol and progesterone binding in vivo permit a more effective screening of estrogens than use of only the classical in vitro method.

Influence of mechanical stretch on growth and protein turnover of rat uterus

1988 ◽  
Vol 254 (5) ◽  
pp. E543-E548 ◽  
Author(s):  
A. J. Douglas ◽  
E. W. Clarke ◽  
D. F. Goldspink
Keyword(s):  
Mechanical Stretch ◽  
Rat Uterus ◽  
Dna Contents ◽  
Extensive Growth ◽  
A New Technique ◽  
Rna And Dna ◽  
Stimulation Of

A new technique has been developed and used to distend the uterus of nonpregnant rats for up to 5 days. Continuous distension of the saline-filled uterus induced rapid and extensive growth of the whole uterus and the myometrium by a combination of hyperplasia and hypertrophy. In both cases, 1 day after this imposition of mechanical stretch significant increases (25-50%) in the protein, RNA, and DNA contents were found, with larger changes (100-250%) being progressively expressed up to 5 days. This stretch-induced growth primarily results from a stimulation of protein synthesis (measured both in vivo and in vitro), with little or no change being evident in the rate of protein breakdown. These findings have been discussed in relation to the role of stretch in the growth of the uterus during pregnancy and stretch-induced responses found in other types of muscle.

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