[Examination of ontogenetic-morphologic growth of cholinergic receptor system in isolated preparation of human trachea in vitro].

Morphologic growth of cholinergic bronchial respiratory system was examined at live and dead newborns. Tracheal smooth musculature was examined at 18 experimental preparations taken by the autopsy after exiting from different factors. Samples were divided into three groups based on gestational weeks. First group: from 23-29 gestational weeks (immature, N=5); second group: from 30-37 gestational weeks (premature, N=7); third group: from 38-41 gestational weeks (mature, N=6). Based on morphological examination of isolated preparations human trachea fingings are the following: in 23-29 week are found nerve endings with axo-axonal synapses mainly at ramification phase of lungs blood vessels net, without trachea bronchial innervations with axo-axonal synapses, and with perichondrial localization. In 30-37 gestational weeks axo-xonal synapses are found in between glands acinus's and vessels net, and also emphatic choline reactivity at lung ganglions: this suggests existing of cholinergic system at alive newborns. At 38-41 gestational weeks exists a wealthy nerve neuromuscular net in smooth tracheal musculature with different vesicles. Choline reactivity is emphasized peri and intrachondrial at lamina propria, at most around sensory glands and in smooth musculature. This suggests that there is no choline reactivity at epithelium and of existence of cholinergic system in tracheal bronchial smooth musculature.