[Effect of palmitate and phorbol ester on synthesis of phosphatidylcholine in isolated guinea pig gastric glands].
To better understand the mechanism of phosphatidylcholine synthesis in the stomach, [3H] choline incorporation into phosphatidylcholine in response to agents which have been shown to induce phosphatidylcholine biosynthesis in other tissues was examined using isolated guinea pig gastric glands. Palmitate and 12-O-tetradecanoyl phorbol 13-acetate (TPA) which has been shown to activate protein kinase C directly, stimulated [3H] choline incorporation into phosphatidylcholine in gastric glands, by 189 +/- 12.9%, and 129 +/- 10.4% of control, respectively (n = 4, p less than 0.01, p less than 0.05). On the other hand, dibutyryl cyclic AMP had no effect on the incorporation. When the glands were pulsed with [3H] choline followed by incubation in the presence of palmitate and TPA for 180 min to see the effects of the agents on the limiting step of the phosphatidylcholine synthesis, phosphatidyl-[3H] choline was increased to 167 +/- 7.5% and 142 +/- 7.5% of control respectively (n = 4, p less than 0.01, p less than 0.05). In parallel to the increase in phosphatidylcholine synthesis, phosphoryl-[3H] choline in the glands incubated with palmitate and TPA was decreased as compared with control. These results suggest that palmitate or TPA may stimulate phosphatidylcholine biosynthesis through the activation of cytidylyltransferase in the stomach.
Nishisaki
H
H
Sakamoto
C
C
Konda
Y
Y
Nakano
O
O
Nagao
M
M
Matozaki
T
T
Baba
S
S
D000818:Animals; D005753:Gastric Mucosa / Q000378:metabolism*; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D010168:Palmitates / Q000494:pharmacology*; D010169:Palmitic Acids / Q000494:pharmacology*; D010713:Phosphatidylcholines / Q000096:biosynthesis*; D013268:Stimulation, Chemical; D013270:Stomach / Q000187:drug effects; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D010168:Palmitates; D010169:Palmitic Acids; D010713:Phosphatidylcholines; D013755:Tetradecanoylphorbol Acetate