Sulphated glycosaminoglycan synthesis by developing rat submandibular gland secretory units.
This study examined the profile of S-GAGs synthesized by presecretory and secretory units isolated from rats at 17, 18 and 21 days in utero and 1, 6 and 35 days after birth. The units were incubated for 2 h in medium containing [35S]-sodium sulphate and then processed and analysed. Secretory units from 17-day embryonic presecretory units produced a S-GAG profile composed of approx. 73% chondroitin sulphate and 26% heparan sulphate. When cells of the embryonic units undergo cytodifferentiation to become secretory cells (18 days in utero), there is a major change in the relative amounts of S-GAG synthesized with 54% of the S-GAG produced being heparan sulphate and 41% chondroitin sulphate. There is a progressive increase in the relative amount of heparan sulphate produced and a concomitant decline in chondroitin sulphate as the secretory compartment of the gland matures. By 35 days after birth, the secretory units produced a S-GAG profile that was greater than 85% heparan sulphate and less than 10% chondroitin sulphate. The ratio of heparan sulphate/chondroitin sulphate production was 0.36 by 17-day embryonic presecretory units and shifted to 9.1 by 35-day postnatal units.
Cutler
L S
LS
Department of Oral Diagnosis, School of Dental Medicine, University of Connecticut Health Center, Farmington 06032.
Christian
C P
CP
Rendell
J K
JK
D000818:Animals; D002809:Chondroitin Sulfates / Q000032:analysis; D006020:Glycopeptides / Q000032:analysis / Q000096:biosynthesis; D006025:Glycosaminoglycans / Q000032:analysis* / Q000096:biosynthesis; D006497:Heparan Sulfate / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D013363:Submandibular Gland / Q000033:anatomy & histology / Q000737:chemistry / Q000196:embryology / Q000378:metabolism*; D013462:Sulfur Radioisotopes
D002809:Chondroitin Sulfates; D006020:Glycopeptides; D006025:Glycosaminoglycans; D006497:Heparan Sulfate; D013462:Sulfur Radioisotopes; C013786:A73025