Miyazaki H, Ohta K, Taneike T, Ohga A
Department of Veterinary Pharmacology, Faculty of Dairy Science, Rakuno Gakuen University, Hokkaido, Japan.
Agents Actions. 1987 Dec;22(3-4):214-22. doi: 10.1007/BF02009049.
Developmental changes in response to histamine were investigated in the oesophagus isolated from the chick between 15 days of incubation and 15 days after hatching. The contraction could be already caused by histamine (20 microM) in the chick oesophagus from 15 days of incubation. The pD2 values for histamine and acetylcholine did not change during the period between 17 days of incubation and 5 days after hatching. The response to histamine (20 microM) was extremely resistant to tetrodotoxin (0.78 microM), procaine (0.2 mM) and atropine (1 microM) during the period between 17 days of incubation and 20 days of incubation. The tetrodotoxin-resistant response was replaced by a tetrodotoxin-sensitive response after hatching. On the other hand, the neuronal response induced by transmural electrical stimulation (20 Hz) or dimethylphenylpiperazinium (20 microM) was uniformly sensitive to tetrodotoxin throughout the periods. Mepyramine (2 microM), but not metiamide (20 microM), inhibited the histamine-induced responses in every age tested. These results suggest that the myogenic receptivity of histamine transiently increases during the terminal period of embryonic development and declines after hatching.
研究了孵化15天至孵化后15天的雏鸡离体食管对组胺反应的发育变化。从孵化15天起，组胺（20微摩尔）就能引起雏鸡食管收缩。在孵化17天至孵化后5天期间，组胺和乙酰胆碱的pD2值没有变化。在孵化17天至孵化20天期间，对组胺（20微摩尔）的反应对河豚毒素（0.78微摩尔）、普鲁卡因（0.2毫摩尔）和阿托品（1微摩尔）具有极强的抗性。孵化后，对河豚毒素抗性的反应被对河豚毒素敏感的反应所取代。另一方面，在整个时期内，经壁电刺激（20赫兹）或二甲基苯基哌嗪鎓（20微摩尔）诱导的神经元反应对河豚毒素始终敏感。在每个测试年龄，美吡拉敏（2微摩尔）而非甲硫咪特（20微摩尔）能抑制组胺诱导的反应。这些结果表明，组胺的肌源性感受性在胚胎发育末期短暂增加，孵化后下降。
