The sympathetic levels of the adrenal medulla are which of the following?

• A. T1-4
• B. T10-11
• C. L2-L4
• D. T12-L2

Answer: (B)

Adrenal medulla is controlled directly by preganglionic sympathetic neurons, so it acts like a sympathetic ganglion. The cell bodies of these preganglionic neurons lie in the spinal cord at the lower thoracic level, specifically around T10 to T11. Their fibers travel with the thoracic splanchnic nerves and reach the adrenal medulla, where they synapse on chromaffin cells. This direct synapse causes chromaffin cells to release catecholamines (epinephrine and norepinephrine) into the bloodstream, producing the widespread sympathetic effects of the fight-or-flight response. Because the input comes from the mid to lower thoracic cord, the relevant sympathetic level is T10–T11.