[Alpha-adrenergic receptors of the human lung parenchyma in destructive tuberculosis]

Adrenergic receptors were studied in human lung parenchyma obtained from 10 patients with tuberculoma after segmental resection within the limits of surrounding normal tissues (controls) as well as from 10 patients with destructive pulmonary tuberculosis. Binding of alpha-adrenergic radioligand 3H-prazosin was saturable with high rate of affinity in lung parenchymal membranes of both normal tissues and tissues impaired with tuberculosis. The Scatchard analysis indicated that the affinity of 3H-prazosin binding was not altered in patients with tuberculosis, while amount of the ligand binding sites was significantly decreased as compared with control preparations (KD = 0.5 +/- 0.9 nM, Bmax = 273.5 +/- 59.9 fmol/mg in controls; KD = 0.5 +/- 0.07 nM, Bmax = 51.7 +/- 7.5 fmol/mg in tuberculous lung parenchyma). beta-Adrenergic and muscarinic acetylcholinergic receptors were studied in lung parenchyma of patients with tuberculosis. Binding parameters of beta-adrenergic ligand 3H-dihydroalprenolol and muscarinic antagonist 3H-quinuclidinyl benzylate were similar to those of control values. Amount of 3H-dihydroalprenolol binding sites was not markedly altered while content of 3H-prazosin binding sites was considerably decreased in lung parenchyma of patients with tuberculosis as compared with normal state. The data obtained suggest that population of alpha-adrenergic receptors was decreased in human lung parenchyma under conditions of destructive tuberculosis.