Effect of beta-adrenoceptor blockers on growth of neurites in spinal ganglia in organotypic tissue culture

We studied the effects of norepinephrine and beta1-adrenoblockers atenolol and metoprolol on the growth of neuritis in organotypic tissue culture of spinal ganglia from 10-12-day chicken embryos. Atenolol (10(-4) M) accelerated the growth of neurites in spinal ganglia by 45%, while metoprolol inhibited the growth of the explants almost in all examined concentrations (10(-10)-10(-4) M). Thus, beta1-adrenoblockers can produce opposite effects on neurite growth. Both atenolol and metoprolol abolished the neurite-stimulating effect of norepinephrine, probably, because this effect is mediated via beta1-adrenoreceptors of spinal ganglia.