The influence of insulin and prolactin on cholesterogenesis and fatty acid synthesis in the rat mammary gland

1986 ◽  
Vol 14 (4) ◽  
pp. 715-716
Author(s):  
ROBIN A. W. SMITH ◽  
BRUCE MIDDLETON ◽  
DAVID W. WEST
Keyword(s):  
Mammary Gland ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Rat Mammary Gland

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

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 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.

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