Pentagastrin-induced release of free fatty acids in healthy volunteers and patients with panic disorder: effect of pretreatment with ethinyl estradiol.

OBJECTIVE

The primary objective of this study was to assess whether pentagastrin-induced panic symptoms are associated with release of free fatty acids (FFAs) in a manner that could explain the mechanism of correlations observed between serum cholesterol levels and frequency and severity of panic attacks in patients with panic disorder (PD). A secondary objective was to assess whether pretreatment with ethinyl estradiol (EE) attenuates pentagastrin-induced release of FFAs.

METHODS

A double-blind, crossover, placebo-controlled study was conducted in which patients with PD and healthy volunteers received 2 injections of pentagastrin, 7-10 days apart, with randomization of the order of pretreatment with placebo and EE.

RESULTS

We found a statistically significant, time-dependent release of FFAs in response to pentagastrin challenge. However, this release of FFAs was not attenuated by pretreatment with EE.

CONCLUSIONS

These results support the hypothesis that release of FFAs in association with panic attacks occurs in a manner similar to the stress-induced lipolysis model. This suggests a possible mechanism for the elevated serum cholesterol levels observed in patients with PD. However, the occurrence of a delayed increase in low-density lipoprotein (LDL) cholesterol following induction of a panic attack remains to be tested in studiesincorporating a placebo injection visit and timed measurements of LDL cholesterol.