Interaction of Cholinergic Function with Mg²⁺-Na⁺-K⁺- Dependent ATP-ASE System of Cells in the Human Fundic Gastric Mucosa

Abstract

Mózsik, G., Nagy, L., Kutas, J. & Tårnok, F. Interaction of cholinergic function with Mg²⁺-Na+-K⁺-dependent ATP-ase system of cells in the human fundic gastric mucosa. Scand. J. Gastroent. 1974, 9, 741–745.

The Mg²⁺-Na⁺-K.,-dependent ATP-ase (EC 3.6.1.3) was biochemically prepared from the human fundic gastric mucosa, and the effects of acetylcholine, carbamylcholine, Neostigmine, and parasympatholytics (atropine, isopro-pamide, Gastrixone®) on this system were studied. The following results were obtained: 1) the total ATP-ase activity was stimulated by acetylcholine (p < 0.001), carbamylcholine (p < 0.001), and Neostigmine (p < 0.001); 2) Mg²⁺-dependent (p < 0.001), total (p < 0.001), and Na+-K+-dependent (p < 0.001) ATP-ase activity was stimulated by acetylcholine; 3) atropine had an inhibitory effect on total (p < 0.001) and Na⁺-K⁺-dependent (p < 0.001) ATP-ase activity, but had no effect on the Mg²⁺-dependent part alone; 4) inhibition of transport (total and Na⁺-K⁺-dependent) ATP-ase by atropine was 100 to 1000 times higher than that by other parasympatholytics; 5) atropine prevented the effects of acetylcholine on the transport ATP-ase system; 6) stimulation and inhibition of transport ATP-ase by cholinergic and anticholinergic drugs depended on the magnitudes of transport ATP-ase activity.

Key-words::

• Acetylcholine
• ATP-ase activity
• enzyme activity
• gastric mucosa
• parasympatholytics