Electrophysiological characterization of single pregnant rat myometrial cells in short-term primary culture
| Autor: | P. Mollard, Jean Mironneau, Chantal Mironneau, T. Amédée |
|---|---|
| Rok vydání: | 1986 |
| Předmět: |
medicine.medical_specialty
Time Factors Primary culture Cell Survival Physiology Cell Action Potentials Biology Membrane Potentials Smooth muscle Pregnancy Internal medicine medicine Animals Microscopy Phase-Contrast Gallopamil Pregnant uterus Cells Cultured Manganese Angiotensin II Myometrium Cobalt Cell Biology Tetraethylammonium Compounds Acetylcholine Rats Electrophysiology Endocrinology medicine.anatomical_structure Cell culture Potassium Female |
| Zdroj: | American Journal of Physiology-Cell Physiology. 250:C47-C54 |
| ISSN: | 1522-1563 0363-6143 |
| DOI: | 10.1152/ajpcell.1986.250.1.c47 |
| Popis: | Smooth muscle cells were isolated from the longitudinal layer of pregnant rat myometrium (18-19 days) and studied either freshly dissociated or during short-term primary culture (until 30 h) using intracellular microelectrode techniques and direct microscopic observation. The isolated myometrial cells excluded trypan blue vital stain and could repetitively contract in response to various stimuli. Electrophysiological studies at 37 degrees C showed normal resting potential (-54.5 +/- 7.5 mV, n = 71). Action potentials with overshoot (+7.8 +/- 4.6 mV, n = 71) could be elicited by intracellular stimulation. Moreover, the membrane potential was largely dependent on the external K+ concentration. The action potential was suppressed in a Ca2+-free solution [with 0.1 mM ethyleneglycol-bis(beta-aminoethylether)-N,N'-tetraacetic acid], and the overshoot amplitude was clearly Ca2+ dependent. The action potential was inhibited by Mn2+ ions (1 mM), Co2+ ions (1 mM), and D 600 (1 microM) but was unaffected by tetrodotoxin (2 microM) and external Na+ removal. Tetraethylammonium chloride (TEA, 10 mM) and 4-aminopyridine (4-AP, 10 mM) increased both overshoot amplitude and duration of the electrical responses. When the cell surface area was measured with light microscopy, the mean specific membrane resistance was 14.8 +/- 4.6 k omega . cm2 (n = 14), and the mean specific membrane capacitance was 2.3 +/- 0.7 microF/cm2 (n = 14). Outward-going rectification was consistently observed in all cells examined. This was either inhibited by TEA and 4-AP (10 mM each) or reduced in the presence of 1 mM Mn2+.(ABSTRACT TRUNCATED AT 250 WORDS) |
| Databáze: | OpenAIRE |
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