Secretoneurin in the human aqueous humor and the absence of an effect of frequently used eye drops on the levels.

Secretoneurin (SN) was detected in the aqueous humor (AH) of patients treated topically with tobramycine eye drops alone or tobramycine and cyclosporine A, tobramycine and diclofenac or tobramycine and rimexolone. The levels of the peptide were found to be higher in the uninflamed human than in the rabbit aqueous humor which may be the result of species differences and/or age-related circumstances. Furthermore, they are approximately one hundred times higher than those of classical neuropeptides indicating release from nerve fibers and/or secretion from non-pigmented ciliary epithelium cells.