Differing effects on superior cervical ganglia in neonatal mice produced by antisera to nerve growth factors from mice and snakes
Banks, B.E.C.; Carstairs, J.R.; Vernon, C.A.
Neuroscience 4(8): 1145-1155
ISSN/ISBN: 0306-4522 DOI: 10.1016/0306-4522(79)90196-9
Rabbit or horse antisera to nerve growth factors [NGF] from mouse salivary glands and the venoms of 5 snakes [Vipera russelli, V. ammodytes ammodytes, Dendroaspis viridis, Agkistrodon rhodostoms and A. piscivorus] were injected into neonatal mice. The mice were killed 10 days later and the superior cervical ganglia removed, weighed and examined histologically. Treatment with antisera to the snake NGF had no effect on ganglion weight, maximum neuronal density or mean neuron diameter. This was true even for the 1 antiserum that, in vitro, showed a weak cross-reactivity with the mouse antigen. Treatment with the antiserum to mouse NGF produced a partial destruction of the superior cervical ganglia (immunosympathectomy). The weights of the ganglia in animals treated for the first 5 days post partum with increasing volumes (a total of 0.5 ml) of antiserum to the mouse factor fell by some 80%, the total neuron number by about 50%, the maximum neuron density by 40% and the mean neuron diameter by 17%; the effect was dose dependent. Caution is required in extrapolating results from in vitro studies on NGF to the situation obtained in vivo, and the inability of snake antisera to produce immunosympathectomy in neonatal mice may result from differences in the antigenic determinants of the mouse and snake NGF. The marked effect of antiserum to the mouse salivary gland factor in neonatal mice reported by earlier workers had been confirmed. No single explanation can be given for the differences in the reduction in neuron numbers found in the present and previous studies. Neither the previous nor the present studies afford evidence that the antiserum directly causes neuronal death.