|
KMID : 0355519810050010005
|
|
Korean Journal of Oral Biology
1981 Volume.5 No. 1 p.5 ~ p.12
|
|
|
EFFECTS OF VARIOUS DRUGS ON MEMBRANE POTENTIAL OF ISOLATED PANCREAS AND SALIVARY GLAND OF RAT
|
|
|
|
|
Abstract
|
|
|
This experiment was performed to elucidate the effects of some drugs controlling the concentration of cyclic nucleotide on membrane potential in isolated salivary gland and pancreas of rats.
Rats of both sexes were anesthetized by intraperitoneal injection of 25% urethan (0.5㎖/100gm). The segments of submaxillary gland and pancreas were isolated and placed in a Perspex tissue bath (20㎖) perfused with 37℃ Krebs-Henseleit solution, aerated with 5% CO_(2)-O_(2) mixture, flowed at about 10㎖/min.
Membrane potentials were measured with glass microelectrodes filled with 3 M KCI, having a tip resistance of 10-30 ㏁. The microelectrode was connected to a pre-amplifier and the membrane potential was recorded on a pen recorder.
The tissues were stimulated by injecting 100 ㎍ acetyicholine directly into the tissue bath using a constant infusion pump for one minute. Theophylline and nicotinic acid were added to control Krebs-Henseleit solution.
The mean resting membrane potential of submaxillary gland cells during perfusion with Krebs-Henseleit solution was -29.9mV and 10 mM nicotinic acid increased the membrane potential to -33.3 mV. During exposure to a control Krebs-Henseleit solution, acetyicholine evoked hyperpolization of cell membrane of submaxillary gland by 16.0 mV. Acetyicholme-induced hyperpolarization was slightly increased by theophylline. But acetyicholine depolarized the membrane by 7.4 mV during exposure to 10 mM nicotinic acid.
In isolated pancreas, mean resting membrane potential was mV during exposure to a control solution. 10 mM theophylline increased the membrane potential to -23.4 mV and 10 mM nicotirLic acid decreased to -17.1mV.
Acetylcholine always decrease the membrane potential during exposure to all solutions in pancreas. In control Krebs-Henseleit solution, the amplitude of the acetylcholine-induced depolarization was similar to that of theophylline solution but nicotinic acid reduced the acetylcholineinduced depolarization.
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|