Fig. 1.

Activity-dependent enhancement of ACh release by NGF. Cultures were preexposed to NGF (10 ng/ml) for 60 min in low K⁺ (6 mm) buffer. ACh release was then evaluated from low-activity (6 mm K⁺) or high-depolarization (25 mm K⁺) conditions for a 15 min period. Columns represent increased ACh (femtomoles per well per minute ± SEM;n = 8) associated with NGF preexposure versus the same depolarizing conditions without NGF preexposure. Significance was determined using Student's t test (*p < 0.001 vs 6 mmK⁺).