in both groups , significant inverse correlations were observed when 24-hr urinary catecholamine levels were examined in relation to measures of both receptor-mediated ( prostaglandin d2 and alpha 2-adrenergic ) and postreceptor-mediated ( naf ) platelet ac enzyme activities , suggesting that circulating catecholamines may regulate platelet ac by heterologous ( agonist-nonspecific ) desensitization of the ac enzyme complex .
C0014442
enzyme
C0026741
enzyme complex