Abstract

The cholinergic component in the sympathetic innervation to the spleen was studied in dogs. This was accomplished by the use of hemicholinium (HC-3) to inhibit transmission in the chohinergic nerves and the use of reserpine and guanethidine to inhibit adrenergic function. The spleen responded normally to electrical stimulation of the splenic nerve at a time when cholinergic transmission was inhibited. These data support the concept of separate chohimiergic and adrenergic fibers in the splenic nerve rather than a cholinergic junction in the adrenergic fibers.

The relationships between the cholinergic and adrenergic components associated with the splenic nerve were studied further by the use of acetylcholine and nicotine. Both of these components of this nerve were found to be involved in both the responses to nicotine and in a possible mechanism for the control of the tone of the splenic capsule. These data are dliscussed in relation to the hypothesis of local chohinergic-adrenergic interaction.