[Adrenergic lung structures following an endogenous and exogenous increase in body serotonin levels]

Adrenergic structures of lungs in 50 mature cats at intraperitoneal serotonin administration and at a short alveolar hypoxia were studied by methods of Falck and Hillarp in the modification of E. M. Krokhina, by argentaffine reaction of Masson--Fontana for serotonin and by histochemical tetrasolium method of Glenner for monoamine oxidase (MAO) activity. Hypoxia 20--30 min duration was produced by means of ligating the inferior-lobular bronchus of the left lung under artificial breathing and the respiratory apparatus A(untypable) under ether narcosis. With changing serotonin level in the organism, the luminescent character of amine-containing and neural structures in the lung change, too. The lung cells of phagocytic nature were stated to be able to absorb and inactivate monoamines of serotonin type. A complete coincidence of topography of luminescent amine-containing structures and formasan granules determining MAO was obtained. Short-term alveolar hypoxia resulted in increasing content of diffuse serotonin in the lung tissue. Endogenic and exogenic increased level of serotonin in the organism resulted in increased MAO activity in the lung tissue.