Development of receptor bronchial system in isolated preparation of piglet trachea in vitro.

In this paper we present the flow research of the development of receptor bronchial system in the first month of extra-uterine life up to the sixth month of development, performed by tracking the reactions of isolated tracheal rings in acetylcholine (Ach), propranolol (P), histamine (Hist), and prostaglandin (PGF2-alfa) in concentrations of: 10-4, 10-3, 10-2 and 10-1 mol/dm3; in piglets of ages: 1 month, 2 months, 4 months and 6 months. Results shows that Ach causes reaction of smooth muscles from the first month of extra-uterine life (p < 0.01) and that Propranolol (P) significantly emphasizes the effect of Ach (p > 0.

Role of meconium in the reaction of airways smooth musculature in the newborn with meconium aspiration syndrome (MAS).

The role of meconium in the respiratory system was studied in newborns, who died from various causes (250 up to 3000 g of weight). We monitored tracheal rings response to dopamine, serotonin and ethanol in different concentrations (dopamine: 0,05 mg/ml, 0,5 mg/ml, 5 mg/ml; serotonin (5-HT): 10-4, 10-3, 10-2, 10-1 mol/dm3; ethanol: 0,02 ml, 0,5 ml, 1,0 ml; 96%). Tracheal smooth musculature tonus (TSM) was examined in 48 tracheal preparations taken after the newborn exitus due to different reasons.

Action of propranolol in the reaction of smooth musculature of tracheal rings induced with acetylcholine, histamine, serotonin (5-HT) and prostaglandin (PGF2-alfa) in vitro and in vivo.

Actions of acetylcholine (ACh), histamines, serotonins (5-HT) and prostaglandins (PGF2-alfa) in concentrations of 10(-4), 10(-3), 10(-2) and 10(-1) mol/dm(3) were analyzed in vitro conditions in isolated specimens of tracheas of 24 pigs, 7 guinea pigs, and dead persons for different reasons (8), in the presence and without presence of propranolol. Whilst, research regarding actions of aerosolized histamines (10 mg, 1%, 2 min), in the presence and without the presence of aerosolized propranolol (20 mg, 2%, 2 min) was done in vivo in 6 healthy persons. Study results show that propranolol does not emphasize contraction of the airways smooth musculature as induced by ACh, histamine, 5-HT and PGF2-alfa in vitro conditions (p>0,1).