Involvement of catecholamines in Haemophilus influenzae induced decrease of beta-adrenoceptor function

The influence of Bordetella pertussis and its constituents on the beta-adrenergic receptor in the guinea pig respiratory system

In the present study, the effect of vaccination of guinea pigs with Bordetella pertussis was investigated, 4 days after treatment, on the cholinergic and beta-adrenergic receptor function in isolated tracheal spirals and the number of beta-adrenoceptor binding sites in guinea pig lung. It was found that B. pertussis caused an impairment in the beta-adrenoceptor function and a decrease in its number. Similar results were obtained with endotoxin. Leucocytosis promoting factor, however, was ineffective. These results indicate that endotoxin is the constituent responsible for the beta-adrenoceptor blocking effects of the bacterium. Also the combined whole cell diphtheria, B. pertussis and tetanus toxoid vaccine induced a beta-adrenoceptor blockade; the acellular vaccine was less effective. The results obtained with the B. pertussis vaccines are discussed in relation to the possible side-effects that sometimes occur after immunization of infants.

Haemophilus influenzae and the beta-adrenergic system: a review

Haemophilus influenzae is a bacterium that often can be isolated from the deeper respiratory airways of patients with chronic asthmatic bronchitis. In the present study the effects of H. influenzae vaccination on guinea pig pulmonary beta-adrenoceptor number and function (in vitro and in vivo) have been evaluated. Functioning of beta-adrenoceptors is determined by measuring the beta-mimetic effect of isoprenaline on the inhibition of anaphylactic mediator release and isolated tracheal strip relaxation. The number of beta-adrenoceptor binding sites was measured by means of a 3H-dihydroalprenolol binding assay. Also the mechanism of action underlying the changes in beta-adrenoceptor functioning was evaluated. Furthermore, it was established that the effect on the beta-adrenoceptor system was not specific for H. influenzae and that other respiratory pathogens were also biologically active in this respect.

Induction in guinea-pigs of airway hyperreactivity and decreased lung beta-adrenoceptor number by 15-hydroperoxy-arachidonic acid

Administration to guinea-pigs of 15-hydroperoxy-arachidonic acid (0.2 mg kg-1 i.p.) caused a 20% reduction of lung beta-adrenoceptor number. Furthermore, in vivo, a hyperreactivity of the airways to nebulized histamine was observed. In contrast, administration of 15-hydroxy-arachidonic acid (0.2 mg kg-1 i.p.) did not cause a significant change in either of these parameters.