Autoradiographic localization of beta-adrenoceptors in asthmatic human lung

Journal Article · Wed Nov 01 00:00:00 EST 1989 · American Review of Respiratory Disease; (USA)

DOI:https://doi.org/10.1164/ajrccm/140.5.1410· OSTI ID:5026080

Spina, D; Rigby, P J; Paterson, J W; Goldie, R G ^[1]

---

1. Univ. of Western Australia, Nedlands, Perth (Australia)

The autoradiographic distribution and density of beta-adrenoceptors in human non-diseased and asthmatic bronchi were investigated using (125I)iodocyanopindolol (I-CYP). Analysis of the effects of the beta-adrenoceptor antagonists on I-CYP binding demonstrated that betaxolol (20 nM, beta 1-selective) had no significant effect on specific grain density in either nonasthmatic or asthmatic human bronchus, whereas ICI-118551 (20 nM, beta 2-selective) inhibited I-CYP binding by 85 +/- 9% and 89 +/- 3%, respectively. Thus, homogeneous populations of beta 2-adrenoceptors existed in bronchi from both sources. Large populations of beta-adrenoceptors were localized to the bronchial epithelium, submucosal glands, and airway smooth muscle. Asthmatic bronchial tissue featured epithelial damage with exfoliated cells associated with luminal mucus plugs. A thickened basement membrane and airway smooth muscle hyperplasia were also evident. High levels of specific I-CYP binding were also detected over asthmatic bronchial smooth muscle, as assessed by autoradiography and quantitation of specific grain densities. Isoproterenol and fenoterol were 10- and 13-fold less potent, respectively, in bronchi from asthmatic lung than in those from nonasthmatic lung. However, this attenuated responsiveness to beta-adrenoceptor agonists was not caused by reduced beta-adrenoceptor density in asthmatic airways. A defect may exist in the coupling between beta-adrenoceptors and postreceptor mechanisms in severely asthmatic lung.

• OSTI ID: 5026080
• Journal Information: American Review of Respiratory Disease; (USA), Vol. 140:5; ISSN 0003-0805
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ASTHMA
PATHOGENESIS
RECEPTORS
BIOLOGICAL LOCALIZATION
SYMPATHOMIMETICS
AUTORADIOGRAPHY
BIOCHEMICAL REACTION KINETICS
BRONCHI
IODINE 125
LUNGS
MAN
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BETA DECAY RADIOISOTOPES
BODY
DAYS LIVING RADIOISOTOPES
DISEASES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPES
KINETICS
MAMMALS
MEMBRANE PROTEINS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PRIMATES
PROTEINS
RADIOISOTOPES
REACTION KINETICS
RESPIRATORY SYSTEM
RESPIRATORY SYSTEM DISEASES
VERTEBRATES
550901* - Pathology- Tracer Techniques