Neurobiological effects of lumbar puncture stress in psychiatric patients and healthy volunteers

Several existing laboratory-based stress paradigms have significant shortcomings for assessing neurobiological correlates of stress in healthy volunteers and severely ill psychiatric patients. We have examined neuroendocrine effects of stress associated with the lumbar puncture (LP) procedure in drug-free depressed and schizophrenic patients and healthy volunteers. Healthy volunteers and depressed patients had significant stress-induced elevations in plasma levels of adrenocorticotropic hormone (ACTH), cortisol, and growth hormone associated with LP. In contrast, schizophrenic patients had no significant elevations in any of the neuroendocrine parameters. Depressed patients' cerebrospinal fluid norepinephrine levels were negatively correlated with stress-induced activation of the hypothalamic-pituitary-adrenal axis. In addition, depressed patients' basal plasma cortisol levels were strongly predictive of stress-related elevations in ACTH, cortisol, and growth hormone. Furthermore, stress-induced changes in schizophrenic patients' cortisol and ACTH levels were not correlated.