{'fraction_non_alphanumeric': 0.05386875612144956, 'fraction_numerical': 0.05582761998041136, 'mean_word_length': 4.741573033707865, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
The effect of Ca2+ antagonists on spontaneous motility from sheep duodenum

Abstract— Longitudinal smooth muscle of the sheep duodenum showed a rhythmic spontaneous activity with an average frequency of 5·6 ± 0·55 phasic movements min−1 and a mean value of the amplitude of phasic contractions of 0·956 ± 0·1 g. When the strips were incubated in Ca2+‐free medium, the spontaneous motility amplitude (SMA) was reduced to 37 ± 8·2% of control values. In Ca2+‐free medium plus EDTA (1 or 2 Mm), the SMA was strongly reduced to 21·9 ± 8·3 and 1·8 ± 1·8%, respectively. Verapamil, nifedipine and diltiazem diminished the SMA. The EC50 value for verapamil was 10−9 M., whereas that for diltiazem was 2 × 10−9 M and for nifedipine was 3 × 10−14 M. Trifluoperazine and TMB‐8 reduced the SMA with EC50 values of 7 × 10−6and 3 × 10−5 m, respectively. The spontaneous activity in the sheep duodenum seemed to be mediated by influx extracellular Ca2+, which enters through potential‐dependent channels and intracellular Ca2+ release.