Bordetella pertussis-induced hyperinsulinaemia without marked ...

B. pertussis vaccine or pulmonary infection produced marked hyperinsulinaemia in mice relative to controls (e.g. control 32 mU/1; B. pertussis infected 113 mU/1). This was associated with a modest relative hypoglycaemia (15-25%). The hyperinsulinaemia was observed only when blood was collected from mice anaesthetized with ether, pentobarbitone, or trichloroethylene but not from unanaesthetized animals. Ether-induced hyperinsulinaemia in B. pertussis was transient. Adrenaline produced marked hyperinsulinaemia in B. pertussis-infected mice whereas it tended to produce hypoinsulinaemia in control animals. The hyperinsulinaemic effect of ether anaesthesia in B. pertussis-infected mice was significantly reduced by beta-adrenoceptor blockade using propranolol. It is suggested (a) that pertussis-infected or vaccinated mice are not chronically hyperinsulinaemic but show elevated insulin concentrations only when subjected to an additional stimulus; (b) that hyperinsulinaemia produced by anaesthesia in pertussis-treated mice is secondary to an altered responsiveness of the insulin-secreting cells to this stimulus; (c) that part of this stimulus may be due to catecholamines released during anaesthesia.