OBJECTIVES: Central neuropeptides modulate behaviour. Plasma levels of neuropeptides may reflect central levels due to specific brain-to-blood transport systems. We purposed to show the modulation of plasma corticotropin releasing hormone (CRH) levels in relation to induced emotions.
DESIGN: Three groups were defined. For experimental groups A and B, an emotionally significant movie fragment was projected for 20 min, while no film projection occurred in group C. Peripheral venous blood samples were collected before, 10 and 60 min after the film or at 0 and 30 min for group C. Total CRH was measured in plasma. Personality was evaluated by the Minnesota Multiphasic Personality Inventory (MMPI).
RESULTS: Plasma CRH levels did not change in the condition with no movie projection - group C - 346 + or - 198 vs. 327 + or - 143 pg/mL. Plasma CRH levels dramatically increased with the projection of a dramatic movie - group A - 394 + or - 147 vs. 791 + or - 636 vs. 803 + or - 771 pg/mL, p<0.05. Plasma CRH increased less markedly in the condition with the projection of a comic movie - group B - 364 + or - 138 vs. 486 + or - 260 vs. 483 + or - 228 pg/mL, p<0.05 for differences between samples 1 and 3. Baseline plasma CRH was significantly and independently related to the neurotic triad and psychotic dyad - partial r=0.328 and 0.267, respectively, p<0.05.
CONCLUSIONS: We conclude that plasma CRH levels increase with experimental emotion induction and that baseline levels are significantly related to behavioural traits. Plasma levels of neuropeptides may reflect central levels and may be useful in clinical medicine and in the study of behavioural disorders....