Annals of Nutrition and Metabolism
Original Paper
Effects in Rats of Dietary Protein Inadequacy on Lactose Production, Milk Volume and Components of the Lactose Synthetase Complex (EC 2.4.1.22)Grimble R.F.a · Mansaray Y.K.C.baDepartment of Nutrition, School of Biochemical and Physiological Sciences, University of Southampton, UK; bDepartment of Chemistry, Njala University College, University of Sierra Leone, West Africa
|
|
Log in to MyKarger to check if you already have access to this content.
KAB
Buy a Karger Article Bundle (KAB) and profit from a discount!
If you would like to redeem your KAB credit, please log in.
Save over 20% compared to the individual article price.
Article / Publication Details
Received: April 18, 1986
Accepted: September 14, 1986
Published online: November 19, 2008
Issue release date: 1987
Number of Print Pages: 6
Number of Figures: 0
Number of Tables: 0
ISSN: 0250-6807 (Print)
eISSN: 1421-9697 (Online)
For additional information: https://www.karger.com/ANM
Abstract
Lactose synthetase (LS) is a complex of α-lactalbumin and N-acetylglucosamine galactosyl transferase (GT). LS is the rate-limiting enzyme in lactose biosynthesis. Lactose is the main osmotic component of milk and may thereby affect milk volume. Dietary protein inadequacy reduces milk volume and lactose content. The study investigates the role of LS activity in these phenomena. Lactating rats were fed adequate and inadequate amounts of protein of high (milk protein) and low (cereal protein) quality. After 14 days LS and GT activity of mammary tissue was measured. Milk volume and lactose content was determined. While GT activity was unaffected by diet, LS activity was reduced by low dietary protein quality. Addition of bovine α-lactalbumin to tissue incubates largely restored the reduced LS activities. Milk volume was affected in a parallel manner to LS activity. A highly significant positive correlation existed between LS activity and total lactose production (r = 0.794; p < 0.001). Dietary protein inadequacy indirectly reduces milk volume by means of a direct effect on the lactalbumin part of the LS complex and, subsequently, lactose biosynthesis.
© 1987 S. Karger AG, Basel
Related Articles:
Article / Publication Details
Received: April 18, 1986
Accepted: September 14, 1986
Published online: November 19, 2008
Issue release date: 1987
Number of Print Pages: 6
Number of Figures: 0
Number of Tables: 0
ISSN: 0250-6807 (Print)
eISSN: 1421-9697 (Online)
For additional information: https://www.karger.com/ANM
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

Get Permission