The accumulation by purified immature porcine Leydig and Sertoli cells of cyclic adenosine 3′,5′-monophosphate in the presence of 1-methyl-3-isobuthylxathine was studied and their respective testosterone and 17β-estradiol production in response to catecholamines was assessed in vitro. These substances increased both basal and FSH-stimulated cyclic adenosine 3′,5′-monophosphate accumulation in Sertoli cells. In contrast, catecholamines slightly enhanced basal cyclic adenosine 3′,5′-monophosphate production but inhibited its human chorionic gonadotropin-stimulated accumulation by Leydig cells. Catecholamines had no effect on basal and stimulated testosterone release by these cells, while dopamine inhibited 17β-estradiol synthesis by Sertoli cells. Using various α- and β-adrenergic agonists and antagonists, β-receptors, likely of the β1-subtype, were shown to be present in both cell lines. Taken together these data suggest the presence of a cyclic adenosine 3′,5′-monophosphate-linked adrenergic receptor in porcine Leydig and Sertoli cells, the role of which remains to be determined.