MECHANISMS INVOLVED IN THE UPTAKE OF D-GLUCOSE INTO THE MILK PRODUCING CELLS OF RAT MAMMARY TISSUE

There is a rapid stimulation of the rate of efflux of 3-O-methyl D-glu cose from intact lactating rat mammary tissue slices in response to a change in the Na+-gradient across the basolateral plasma membrane. RNA extracted from lactating glands contains a 4 kb transcript which hybr idises with the cDNA for rabbit A fraction of the mammary gland cells which is enriched in endoplasmic, plasma membranes contains a protein that is immunologically similar to the Na+-dependent D-glucose symport er present in the plasma membrane of polarised epithelial cells, e.g., rabbit enterocytes, ovine enterocytes and parotid acinar cells. (C) 1 995 Academic Press, Inc.