Influence of age and parity on the susceptibility of rat mammary gland epithelial cells in primary cultures to 7,12-dimethylbenz(a) anthracene

In Vitro ◽  
1981 ◽  
Vol 17 (10) ◽  
pp. 877-884 ◽  
Author(s):  
Jose Russo ◽  
Gerald Wilgus ◽  
Lawrence Tait ◽  
Irma H. Russo
1988 ◽  
Vol 254 (1) ◽  
pp. 33-38 ◽  
Author(s):  
C K Chao ◽  
E A Pomfret ◽  
S H Zeisel

The neonatal mammal requires especially large amounts of choline to sustain growth. Much of this choline is derived from the newborn's only source of food, milk. The concentration of choline in rat milk [182 +/- 24 microM (S.E.M.)] was much higher than that in maternal serum (11.6 +/- 0.9 microM), suggesting that a mechanism capable of concentrating choline into milk must exist. We characterized choline uptake by mammary epithelial cells (the site of milk production) of the lactating rat. We observed two uptake processes, one saturable and obeying Michaelis-Menten kinetics, and the other non-saturable and linear. At physiological blood choline concentrations, the saturable component of choline uptake predominated. The saturable component had Kapp. = 35 +/- 16 microM, and Vmax. = 1.24 +/- 0.19 nmol/h per mg of protein. Saturable uptake of choline was inhibited by hemicholinium-3. Ca2+ was required for uptake, but Mg2+ was not. Replacement Na+ with K+, Li+ or sucrose inhibited transport. Ouabain did not inhibit choline uptake. Choline concentration in epithelial cells was 67.7 +/- 1.9 nmol/g wet wt. at the start of incubation at 37 degrees C and rose to 80.9 +/- 6.5 nmol/g wet wt. over 30 min. Much of the choline accumulated by the mammary gland (in the presence of endogenous concentrations of choline) remained in the form of choline (50 +/- 1.2%), phosphatidylcholine (12 +/- 2.3%), lysophosphatidylcholine (0.1 +/- 0.03%), betaine (7 +/- 0.3% and phosphocholine (6 +/- 0.5%). In addition, we isolated 25 +/- 1.2% of choline-derived radiolabel in an unidentified compound.


2010 ◽  
Vol 285 (17) ◽  
pp. 13092-13106 ◽  
Author(s):  
Stefano J. Mandriota ◽  
Raphaële Buser ◽  
Laurence Lesne ◽  
Christelle Stouder ◽  
Vincent Favaudon ◽  
...  

2016 ◽  
Vol 139 (12) ◽  
pp. 2781-2790 ◽  
Author(s):  
Stefano J. Mandriota ◽  
Mirna Tenan ◽  
Paolo Ferrari ◽  
André‐Pascal Sappino

2000 ◽  
Vol 39 (5) ◽  
pp. 194-200 ◽  
Author(s):  
S. Obermeier ◽  
B. Hüselweh ◽  
H. Tinel ◽  
R.H.K. Kinne ◽  
C. Kunz

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