Alterations in adenyl cyclase activity and glucose utilization of Bordetella pertussis-sensitized mouse spleen

Abstract

The effects of Bordetella pertussis sensitization on the cyclic AMP content, adenyl cyclase activity and glucose uptake and utilization of mouse spleen were examined. Injection of B. pertussis vaccine into mice resulted in a decrease (36 per cent) in cyclic AMP content of the spleens 4 days after vaccination, while decrease in blood glucose (53 per cent) occurred within 6 hr. Experiments in vitro using membrane fractions of spleens have shown that epinephrine, norepinephrine, isoproterenol and sodium fluoride stimulated adenyl cyclase activity to a much less extent in those derived from pertussis-sensitized mice than in those from nonsensitized mice. When nonsensitized mice were injected with propranolol (5–40 mg/kg), a beta-adrenergic blocking agent, cyclic AMP content decreased (58 per cent) to a level equivalent to that obtained by pertussis sensitization. Whereas epinephrine and aminophylline enhanced spleen cyclic AMP content (62 per cent) and blood glucose levels (115 per cent), pretreatment with propranolol blocked this enhancement. These observations are consistent with the hypothesis that adenyl cyclase activity in the spleen is a function of a beta-adrenergic receptor which is subject to blockade by pertussis sensitization. Uptake and utilization of glucose is markedly enhanced in spleen slices of pertussis-sensitized animals compared with that in nonsensitized, reflecting a probable generalized increase in peripheral uptake which may, in part, explain the hypoglycemia and adjuvancy observed in sensitization.