Beta-1 adrenoceptor antagonists potentiate the anticonvulsive effect of swim stress in mice

Pharmacol Biochem Behav. 2000 Nov;67(3):507-10. doi: 10.1016/s0091-3057(00)00385-3.

Abstract

To explore the possible involvement of beta adrenoceptor antagonists in the previously observed anticonvulsive effect of swim stress, the mice were, prior to administration of convulsants, pre-treated with propranolol (a non-selective beta adrenoceptor antagonist), betaxolol (a selective beta-1 adrenoreceptor antagonist), or ICI 118,551 (a selective beta-2 adrenoreceptor antagonist). In control unstressed animals, only propranolol [10 mg/kg, intraperitoneally (ip)] produced a significant change. It enhanced the threshold dose of picrotoxin producing tonic hindlimb extension. However, in swim-stressed animals, propranolol enhanced doses of picrotoxin producing tonic hindlimb extension and death, while betaxolol (20 mg/kg, i.p.) enhanced doses of picrotoxin producing running/bouncing clonus, tonic hindlimb extension and death. Pre-treatment with ICI 118,551 (4 mg/kg, i.p.) failed to affect doses of picrotoxin producing convulsions and death. The results demonstrate that blockade of beta-1 adrenoceptors potentiates the anticonvulsant effect of swim stress against convulsions produced by picrotoxin, a noncompetitive GABA(A) receptor antagonist.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenergic beta-1 Receptor Antagonists*
  • Animals
  • Betaxolol / pharmacology
  • Convulsants
  • Male
  • Mice
  • Mice, Inbred CBA
  • Picrotoxin
  • Propanolamines / pharmacology
  • Propranolol / pharmacology
  • Receptors, Adrenergic, beta-1 / physiology
  • Seizures* / chemically induced
  • Seizures* / mortality
  • Stress, Physiological*
  • Swimming

Substances

  • Adrenergic beta-1 Receptor Antagonists
  • Convulsants
  • Propanolamines
  • Receptors, Adrenergic, beta-1
  • Picrotoxin
  • ICI 118551
  • Propranolol
  • Betaxolol