Effects of cyclic nucleotide derivatives on the Na+ pump activity and the release of sialic acid in dog submandibular glands.
The effects of dibutyryl cyclic AMP (DBcAMP) and cyclic GMP (DBcGMP) on the Na+,K+-ATPase activity and the release of sialic acid were investigated in dog submandibular gland pieces. The Na+,K+-ATPase activity and the release of sialic acid were significantly stimulated in the presence of 100 microM DBcAMP or in the combination of 3 mM NaF and 50 microM 1-methyl-3-isobutylxanthin but were not by DBcGMP. When the pieces were incubated in the Ca2+-free medium, the DBcAMP-induced Na+,K+-ATPase activity slightly decreased but the sialic acid release was unaffected. The corresponding results were also observed in the Ca2+-free medium supplemented with 2 mM EGTA. These results suggest that the cytosolic cyclic AMP modifies the Na+ pump activity.
Komabayashi
T
T
Department of Pharmacology, Tokyo College of Pharmacy, Japan.
Izawa
T
T
Nakamura
T
T
Suda
K
K
Shinoda
S
S
Tsuboi
M
M
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D003994:Bucladesine / Q000494:pharmacology*; D006152:Cyclic GMP / Q000031:analogs & derivatives*; D003995:Dibutyryl Cyclic GMP / Q000494:pharmacology*; D004285:Dogs; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D012794:Sialic Acids / Q000378:metabolism*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013363:Submandibular Gland / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*
D012794:Sialic Acids; D003995:Dibutyryl Cyclic GMP; D003994:Bucladesine; D000254:Sodium-Potassium-Exchanging ATPase; D006152:Cyclic GMP