Unknown

Dataset Information

0

Metabolic adaptations during lactogenesis. Fatty acid and lactose synthesis in cow mammary tissue.


ABSTRACT: 1. Mammary-tissue biopsies were obtained from multiparous cows at 30 and 7 days pre partum and 7 and 40 days post partum. Investigations of the effect of lactogenesis on fatty acid and lactose synthesis involved measurements of biosynthetic capacity (tissue-slice incubations in vitro) and activities of relevant enzymes. 2. Fatty acid synthesis from acetate increased over 20-fold from 30 days pre partum to 40 days post partum. Changes in the lipogenic capacity of mammary-tissue slices more closely paralleled increases in the activities of acetyl-CoA carboxylase (EC 6.4.1.2) and acetyl-CoA synthetase (EC 6.2.1.1) than of other enzymes involved in acetate incorporation into fatty acids or in NADPH generation. 3. Lactose biosynthesis by mammary-tissue slices, lactose synthetase activity (EC 2.4.1.22) and alpha-lactalbumin concentration were all negligible at 30 days pre partum but increased 2.5-4-fold between 7 days pre partum and 40 days post partum. Phosphoglucomutase (EC 2.7.5.1), UDP-glucose pyrophosphorylase (EC 2.7.7.9) and UDP-glucose 4-epimerase (EC 5.1.3.2) had substantial activities at 30 days pre partum and increased less dramatically during lactogenesis. 4. Results are consistent with acetyl-CoA carboxylase and perhaps acetyl-CoA synthetase representing the regulatory enzyme(s) in fatty acid synthesis, with lactose synthetase (alpha-lactalbumin) serving a similar function in lactose biosynthesis.

SUBMITTER: Mellenberger RW 

PROVIDER: S-EPMC1166010 | biostudies-other | 1973 Nov

REPOSITORIES: biostudies-other

Similar Datasets

| S-EPMC1166222 | biostudies-other
| S-EPMC4880877 | biostudies-literature
| S-EPMC1166063 | biostudies-other
| S-EPMC1161904 | biostudies-other
| S-EPMC5934875 | biostudies-literature
| S-EPMC1161529 | biostudies-other
2015-04-01 | GSE62728 | GEO
| S-EPMC1135497 | biostudies-other
| S-EPMC1174313 | biostudies-other
2015-04-01 | E-GEOD-62728 | biostudies-arrayexpress