Steroids and Cromolyn for Treatment of Chronic Asthma

Abstract

Adrenal corticosteroids retain a unique place in the treatment of asthma. The various kinds bind to the same receptor protein in the cytosol of cells in the target tissues. Thus, the effects of several steroids given concomitantly by different routes, eg, oral and aerosol, are summative. The potency of a particular steroid reflects how tightly it binds to the receptor. 1 Rousseau GG Baxter JD Tomkins GM. Glucocorticoid receptors: relations between steroid binding and biological effects. J Mol Biol. 1972; 67: 99-115 Crossref PubMed Scopus (453) Google Scholar ,2 Chan L O'Malley BW Steroid hormone action: recent advances. Ann Intern Med. 1978; 89: 694-701 Crossref PubMed Scopus (46) Google Scholar Their anti-asthmatic effect is due, in part, to the resulting complex stimulating the release of inhibiting proteins (probably from leukocytes) which modulate the synthesis and breakdown of inflammatory mediators by other cells. 3 Flower RJ Blackwell GJ. Anti-inflammatory steroids induce biosynthesis of a phospholipase A2 inhibitor which prevents prostaglandin generation. Nature. 1979; 278: 456-459 Crossref PubMed Scopus (698) Google Scholar -5 Moore PK Hoult JRS Anti-inflammatory steroids reduce tissue PG synthetase activity and enhance PG breakdown. Nature. 1980; 288: 269-270 Crossref PubMed Scopus (50) Google Scholar Steroids facilitate the action of adrenergic bronchodilator drugs, 6 Shenfield GM Hodson ME Clarke SW Paterson JW. Interaction of corticosteroids and catecholamines in the treatment of asthma. Thorax. 1975; 30: 430-435 Crossref PubMed Scopus (41) Google Scholar ,7 Ellul-Micallef R Fenech FF. Effect of intravenous prednisolone in asthmatics with diminished adrenergic responsiveness. Lancet. 1975; 2: 1269-1270 Abstract PubMed Scopus (114) Google Scholar apparently by altering the ratio of alpha to beta adrenergic receptors on cell surfaces. 8 Szentivanyi A. The radioligand binding approach in the study of lymphocytic adrenoceptors and the constitutional bases of atopy. J Allerg Clin Immunol. 1980; 65: 5-11 Abstract Full Text PDF PubMed Scopus (39) Google Scholar -10 Mano K Akbarzadeh A Koesnadi K Sano X Bewtra A Townley R. The effect of hydrocortisone on beta adrenergic receptors in lung tissue. J Allerg Clin Immunol. 1979; 63: 147 Google Scholar In this way, they may influence not only smooth muscle and leukocyte responses, but also carotid body responsiveness to hypoxemia.