Characterization of bovine neutrophil β₂‐adrenergic receptor function

Abstract

This study compares bovine leukocyte beta-adrenergic receptor densities to that of the rat, demonstrates for the first time a functional beta(2)-adrenergic receptor signaling pathway in steer neutrophils, and investigates the effect of an inflammatory stimulus on that signaling pathway. The beta(1)-/beta(2)-adrenergic antagonist ([3H])CGP-12177 demonstrated that rat lymphocyte specific binding-site density was highest, followed by steer and dairy cow lymphocytes, and lastly steer and dairy cow neutrophils. The beta(2)-adrenergic agonist terbutaline stimulated steer neutrophil adenosine 3,5-cyclic monophosphate (cAMP) production, an effect increased by inclusion of > or = 1 x 10(-8) M phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C. Both terbutaline and the nonselective phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) independently decreased steer neutrophil superoxide anion production in a concentration-dependent manner, with 1 x 10(-4) M IBMX enhancing both the potency and efficacy of the terbutaline effect (up to 74% reduction in superoxide anion production). Superoxide anion production was also reduced by the synthetic cAMP analog 8-bromo-cAMP, which increased the potency of the IBMX effect on superoxide anion production. Taken together, these data demonstrate the presence of a beta(2)-adrenergic receptor signaling pathway in bovine neutrophils much like that described in other animal species, as well as the potential for an inflammatory stimulus to alter its function.

Interaction between stress hormones and phagocytic cells and its effect on the health status of dairy cows: A review

“…In bovine PMNs, the β2-adrenergic receptor signaling pathway is similar to that described in other species as well as the potential for an inflammatory stimulus to alter its function [ 60 ]. In physiologically stressed cows, high levels of blood catecholamine were involved in the impairment of CD-11b-mediated PMNs functions [ 61 ].…”

Adrenergic Tone as an Intermediary in the Temperament Syndrome Associated With Flight Speed in Beef Cattle

“…Adrenergic activity exerts an influence over immune functions via sympathetic innervation of primary and secondary lymphoid organs, and through activation of adrenergic receptors on leukocytes, especially cells of the monocyte-macrophage lineage (LaBranche et al, 2010;Irwin and Cole, 2011;Kenney and Ganta, 2011;Wohleb, 2019). In sheep, the beta agonist clenbuterol suppresses antibody responses to vaccination (Spencer and Oliver, 1996).…”