ROLE OF BETA-ADRENOCEPTOR ANTAGONISTS IN THE CONTROL OF KINDLING MODELS IN RATS

AIM　To study the role of β-adrenoceptors (β-AR) and their subtypes in the control of kindling models in rats. METHODS　Electrical amygdala kindling, pentylenetetrazol (PTZ) kindling models in rats and maximal electroshock (MES) in mice were used to observe the effects of β-AR agonists and antagonists. RESULTS　The β-AR antagonist propranolol 15 mg.kg^-1 ip delayed the development of amygdala kindling; while propranolol 1～20 mg.kg^-1 ip and β₁-AR antagonist metoprolol 25～400 mg.kg^-1 ig significantly increased the afterdischarge threshold and reduced the seizure severity in both kindling models (P<0.01). β₁-AR agonist dobutamine completely reversed the inhibitory effect of propranolol, while the β₂-AR agonist terbutaline showed no effect on propranolol. Metoprolol 200 and 800 mg.kg^-1 ig significantly inhibited MES in mice (P<0.01). CONCLUSION　Central β₁-AR is involved in the inhibitory effects on amygdala kindling and PTZ kindling models in rats.