Inhibition of Fatty Acid Synthesis in Rat Mammary Gland Slices by Cortisone in Vitro and its Antagonism by Insulin

Nature ◽  
1952 ◽  
Vol 169 (4298) ◽  
pp. 447-449 ◽  
Author(s):  
JUDITH H. BALMAIN ◽  
S. J. FOLLEY ◽  
R. F. GLASCOCK
Keyword(s):  
Mammary Gland ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Rat Mammary Gland

scholarly journals Effects of adrenal corticoids on fatty acid synthesis in mammary gland slices in vitro

1955 ◽  
Vol 60 (1) ◽  
pp. 102-108 ◽  
Author(s):  
Mary L. McNaught ◽  
R. F. Glascock ◽  
Judith H. Balmain ◽  
S. J. Folley
Keyword(s):  
Mammary Gland ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis

Prolactin-stimulated polymerization of acetyl-CoA carboxylase in explants of mid-pregnant rat mammary gland

2001 ◽  
Vol 68 (3) ◽  
pp. 351-355 ◽  
Author(s):  
JULIUS E. OBEN ◽  
RAYMOND R. DILS
Keyword(s):  
Mammary Gland ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Specific Activity ◽  
Acid Synthesis ◽  
Acetyl Coa Carboxylase ◽  
Acetyl Coa ◽  
Pregnant Rat ◽  
Rat Mammary Gland ◽  
Total Enzyme

Prolactin significantly increased the rate of fatty acid synthesis in explants of mid-pregnant rat mammary gland cultured for 96 h with insulin plus corticosterone. Under these conditions, prolactin increased the specific activity of total acetyl-CoA carboxylase in nuclear-free homogenates of explants by 2·6, and increased the proportion of the enzyme in the active polymeric form from 0·44 to 0·89. Removal of prolactin after 48 h in culture decreased the specific activity of the total enzyme by about half, and decreased the proportion as polymer to 0·52. The results show that prolactin plays a major role in mid-pregnant rat mammary gland in the polymerization which accompanies increased activity of the total enzyme and increased rate of fatty acid synthesis.

scholarly journals Interactions of insulin, corticosterone and prolactin in promoting milk-fat synthesis by mammary explants from pregnant rabbits

1972 ◽  
Vol 129 (4) ◽  
pp. 929-935 ◽  
Author(s):  
Isabel A. Forsyth ◽  
Christopher R. Strong ◽  
Raymond Dils
Keyword(s):  
Fatty Acids ◽  
Mammary Gland ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Long Chain Fatty Acids ◽  
Medium Chain ◽  
Long Chain ◽  
Chain Fatty Acids

1. The rate of fatty acid synthesis by mammary explants from rabbits pregnant for 16 days or from rabbits pseudopregnant for 11 days was stimulated up to 15-fold by culturing for 2–4 days with prolactin. This treatment initiated the predominant synthesis of C8:0 and C10:0 fatty acids, which are characteristic of rabbit milk. 2. Inclusion of insulin in the culture medium increased the rate of synthesis of these medium-chain fatty acids. By contrast the inclusion of corticosterone led to the predominant synthesis of long-chain fatty acids. When explants were cultured for 2–4 days with insulin, corticosterone and prolactin, the rate of fatty acid synthesis increased up to 42-fold, but both medium- and long-chain fatty acids were synthesized. 3. These results show that the stimulus to mammary-gland lipogenesis and the initiation of synthesis of medium-chain fatty acids observed between days 16 and 23 of pregnancy in the rabbit can be simulated in vitro by prolactin alone. 4. When mammary explants from rabbits pregnant for 23 days were cultured for 2 days with insulin, corticosterone and prolactin, the rate of fatty acid synthesis increased fivefold, but there was a preferential synthesis of long-chain fatty acids. Culture with prolactin alone had little effect on the rate or pattern of fatty acids synthesized. 5. The results are compared with findings in vivo on the control of lipogenesis in the rabbit mammary gland, and are contrasted with the known effects of hormones in vitro on the mammary gland of the mid-pregnant mouse.

scholarly journals Lactose and fatty acid synthesis in lactating-rat mammary gland. Effects of starvation, re-feeding, and administration of insulin, adrenaline, streptozotocin and 2-bromo-α-ergocryptine

1984 ◽  
Vol 219 (1) ◽  
pp. 173-180 ◽  
Author(s):  
L E Bussmann ◽  
S Ward ◽  
N J Kuhn
Keyword(s):  
Mammary Gland ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Milk Composition ◽  
Standard Diet ◽  
Partial Recovery ◽  
Rat Mammary Gland ◽  
Lactose Synthesis ◽  
Intracellular Glucose

Lactose synthesis and fatty acid synthesis in intact lactating-rat mammary gland were measured simultaneously by incorporation of [U-14C]glucose and of both [U-14C]glucose and 3H2O respectively. Both processes were almost abolished by overnight starvation. Self-re-feeding caused recovery of lipogenesis to 100% of normal by 2 h and to 170% by 5 h. Lactose synthesis recovered to 80% of normal by 5 h. Food intubated to starved rats caused partial recovery in 3 h, standard diet favouring lactose synthesis and sugars favouring lipogenesis. Casein and starch were ineffective. Olive oil intubated to fed rats suppressed lipogenesis greatly and lactose synthesis slightly. Paraffin oil or water partly mimicked these effects. Adrenaline (subcutaneous) decreased lipogenesis from glucose, whereas insulin (subcutaneous) caused hypoglycaemia associated with loss of lactose synthesis but unchanged fatty acid synthesis. Streptozotocin and 2-bromo-alpha-ergocryptine (CB-154) impaired lipogenesis but not lactose synthesis. The results are interpreted in terms of competition for intracellular glucose by biosynthetic pathways for lactose and fat, and the possible implications for variations in milk composition are discussed.

scholarly journals Evidence for a role of insulin in the regulation of lipogenesis in lactating rat mammary gland. Measurements of lipogenesis in vivo and plasma hormone concentrations in response to starvation and refeeding

1978 ◽  
Vol 176 (1) ◽  
pp. 343-346 ◽  
Author(s):  
A M Robinson ◽  
J R Girard ◽  
D H Williamson
Keyword(s):  
Mammary Gland ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Plasma Insulin ◽  
Acid Synthesis ◽  
Plasma Insulin Concentration ◽  
Rat Mammary Gland ◽  
Plasma Hormone

Fatty acid synthesis in the mammary gland of lactating rats in vivo was 5-fold higher than in the liver. Starvation decreased fatty acid synthesis in the gland 50-fold, whereas refeeding for 2h completely reversed this change. The plasma insulin concentration decreased 2-fold in starvation and was restored to the fed-rat value on refeeding. Glucagon and prolactin concentrations did not always change in parallel with lipogenesis, suggesting that insulin may be a regulator of this process in the gland.

Sign in / Sign up

Export Citation Format

Share Document