In our research we have aimed at studying the blood- and cerebrospinal fluid catecholamines' behaviour by means of von Euler-Floding's method, in a group of 30 patients, between 33 and 83 years, with chronic obstructive bronchopneumopathy, evolving from over ten years (even in younger persons). The total catecholamines in the cerebrospinal fluid have double values as against those in the blood, corresponding to the proportion found in a group of healthy subjects. On the contrary, the catecholamine fractions, occurring both in the blood and in the cerebrospinal fluid, have a diffent behaviour as against the normals, the adrenaline percentage exceeding by far the value of 23% recorded by these latter, going up to 46.95% in the blood and up to 47.68 in the cerebrospinal fluid. The increase of the adrenaline percentage may represent a pathogenetical factor, added to the other metabolic and hemodynamic factors, in the genesis of the chronic cardiopneumopathy; and the noxious effect acting on the whole myocardium supports the thesis according to which, earlier or later, in chronic obstructive bronchopneumopathy the left ventricle starts to suffer, as an integrant part of the clinico-morphological image.