Flow research of the development of receptor bronchial system was conducted in this work since the first day in 4th week of extra-uterine life, by following reactions of isolated tracheal rings in acetylcholine (Ach), histamine (Hist), and prostaglandin (PGF2-alfa) in concentrations of: 10-4, 10-3, 10-2, 10-1, mol/dm3, at piggys of ages: 1 day, 1 week, 2 weeks and 4 weeks. Results shows that Ach causes reaction of smooth muscles since the first day of extra-uterine life in a significant way (p0.1). Whereas histamine, and PGF2- alpha does not cause constriction of tracheal smooth musculature (MLT) in the first days of extra-uterine life. This shows that cholinergic and adrenergic system in airways of pigs is developed in intrauterine life and reaction was registered since the first day of extra-uterine life, whereas other receptor systems are developed in later weeks of extra-uterine life. Potential explanation of this mechanism of constriction of tracheal rings smooth musculature, dependence-age, is increase of the Calcium ions influx throughout receptor-activating and voltage operating channels in cells of the pigs tracheal smooth musculature in the first days of extra-uterine life.
Key words: Pigs trachea, Ach, Histamine, and PGF2-alfa.
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