Stress, endocrine & the HPA axis

DSIP’s clearest human signal is not about sleep at all

Ironically, the most reproducible human DSIP effect is endocrine, not hypnotic. Intravenous DSIP repeatedly lowered the stress hormone precursor ACTH, while leaving cortisol and vasopressin responses largely intact, hinting at a selective touch on the HPA axis.

This unit follows that stress-axis story, the LH and somatostatin findings, and the Cushing-syndrome data that complicates any tidy "DSIP equals more deep sleep" narrative.