Neuroactive steroid levels in patients with generalized anxiety disorder

Serum levels of allopregnanolone, pregnenolone sulfate, and dehydroepiandrosterone sulfate were measured in 8 male patients with generalized anxiety disorder (GAD) and 8 healthy control subjects. Results suggest that patients with GAD have significantly lower levels of pregnenolone sulfate than control subjects.

Effect of ethinyl estradiol on the panic response to the panicogenic agent pentagastrin

BACKGROUND

Panic disorder (PD) symptomatology has been reported to be altered by hormonal events or treatments which affect estrogen levels. Coryell et al. [Arch. Gen. Psychiatry, 39 (1982) 701-703; Am. J. Psychiatry, 143 (1986) 508-510] have suggested that the increased cardiovascular risk associated with PD is significantly greater in males, alluding to a potential cardioprotective effect of female hormones in the context of panic attacks. In the present study, we were, therefore, interested in elucidating the role of estrogen in modulating the behavioural and cardiovascular responses induced by the panicogenic agent pentagastrin, a cholecystokinin-B (CCK(B)) receptor agonist.

METHODS

A double-blind cross-over placebo-controlled design with randomization of the order of a 3-day pretreatment of ethinyl estradiol (EE) (50 microg/day) or placebo was used to assess the effect of a 30-microg i.v. bolus injection of pentagastrin on panic symptom intensity and on increases in heart rate (DeltaHR), systolic (DeltaSBP) and diastolic (DeltaDBP) blood pressure following each pretreatment. Subjects were 9 male healthy controls and 11 male PD patients.

RESULTS

EE pretreatment did not significantly reduce the pentagastrin-induced panic symptom scale (PSS) scores and had no effect on DeltaDBP or DeltaSBP. EE did, however, attenuate the pentagastrin-induced increase in HR in both PD patients and healthy controls.

LIMITATIONS

Only male subjects were included in the present study; however, we are currently investigating the influence of female gonadal hormones on the panic response to pentagastrin in female PD patients and healthy controls.

CONCLUSION

Our results suggest that estrogens may display cardioprotective effects in the context of panic attacks.

The influence of Type A behavior pattern on the response to the panicogenic agent CCK-4

OBJECTIVES

Review of the literature equivocally suggests that subjects with Type A behavioral pattern (TABP) compared to subjects with Type B behavioral pattern display an increased sympathetic activity, a condition associated with sudden cardiac death. The objective of this study was to determine whether healthy subjects classified as Type A or Type B differed in their reactivity to the beta 1 and beta 2 receptor agonist isoproterenol and to the panicogenic agent cholecystokinin-tetrapeptide (CCK-4). By comparing reactivity to CCK-4 after pretreatment with placebo or propranolol, a beta 1 and beta 2 receptor antagonist, the role of the beta adrenergic system in the hypothesized increased response of Type A subjects to CCK-4 was also assessed.

METHODS

The study used a randomized, double-blind, placebo-controlled design. Twenty-seven Type A or B subjects were included in the study. The reactivity to isoproterenol was assessed with the CD25 of isoproterenol (i.e., the intravenous dose of isoproterenol necessary to increase the heart rate of 25 bpm). The panic symptom response and the cardiovascular response to bolus injection of 50 microg of CCK-4 was assessed in subjects pretreated with either propranolol or placebo infusions prior to the CCK-4 challenge. An additional group of subjects was recruited and these subjects received a placebo infusion pretreatment before an injection of placebo.

RESULTS

The CD25 was significantly greater in Type A subjects than in Type B subjects. No difference was found among the groups on behavioral sensitivity to the CCK-4 challenge. However, CCK-4-induced maximum increase in heart rate was greater in Type A subjects.

CONCLUSION

Our finding that Type A subjects exhibited greater CD25 of isoproterenol and greater increases in heart rate following CCK-4 administration compared to Type B subjects suggests that peripheral beta-receptor sensitivity may be increased in individuals with TABP.

Arginine-vasopressin and oxytocin response to cholecystokinin-tetrapeptide

This study examined the effects of i.v. administration of cholecystokinin-tetrapeptide (CCK-4) on plasma release of arginine vasopressin (AVP) and oxytocin (OT) in women with premenstrual dysphoric disorder (PMDD) and control women, during both the follicular phase and the luteal phase of their menstrual cycle. Plasma AVP and OT concentrations increased following CCK-4 administration. AVP and OT response to CCK-4 was similar for PMDD and control women and unaffected by menstrual cycle phase. AVP and OT may play a role in the hypothalamo-pituitary adrenal (HPA) axis activity associated with the panic response induced by CCK-4.

Response to pentagastrin after acute phenylalanine and tyrosine depletion in healthy men: a pilot study

OBJECTIVE

To assess the effects of the acute depletion of the catecholamine precursors phenylalanine and tyrosine on mood and pentagastrin-induced anxiety.

DESIGN

Randomized, double-blind controlled multiple crossover study.

SETTING

University department of psychiatry.

PARTICIPANTS

6 healthy male volunteers.

INTERVENTIONS

3 treatments were compared: pretreatment with a nutritionally balanced amino acid mixture, followed 5 hours later by a bolus injection of normal saline placebo; pretreatment with a balanced amino acid mixture, followed by a bolus injection of pentagastrin (0.6 microgram/kg); and pretreatment with an amino acid mixture without the catecholamine precursors phenylalanine or tyrosine, followed by pentagastrin (0.6 microgram/kg).

OUTCOME MEASURES

Scores on the panic symptom scale, a visual analogue scale for anxiety, the Borg scale of respiratory exertion and the Profile of Mood States Elation-Depression Scale.

RESULTS

Pentagastrin produced the expected increases in anxiety symptoms, but there was no significant or discernible influence of acute phenylalanine and tyrosine depletion on anxiety or mood.

CONCLUSIONS

These pilot data do not support further study using the same design in healthy men. Under these study conditions, phenylalanine and tyrosine depletion may have larger effects on dopamine than noradrenaline. Alternative protocols to assess the role of catecholamines in mood and anxiety are proposed.

Behavioral, cardiovascular, and neuroendocrine profiles following CCK-4 challenge in healthy volunteers: a comparison of panickers and nonpanickers

Healthy subjects who panic following systemic cholecystokinin-tetrapeptide (CCK-4) challenge typically exhibit a symptom profile reminiscent of that evident among panic patients. However, the biological concomitants of CCK-4-induced panic in healthy subjects remain obscure. Accordingly, we evaluated the behavioral, cardiovascular, and neuroendocrine effects of CCK-4 in panickers and nonpanickers. Predictably, subjects who panicked with CCK-4 experienced more intense symptoms of panic and greater increases in ratings of fearful and anxious mood than did subjects who did not panic. CCK-4-induced increases in diastolic blood pressure, adrenocorticotropic hormone, prolactin, and growth hormone secretion were also significantly enhanced in subjects who panicked. The results of this study demonstrate that the behavioral experience of CCK-4-induced panic in healthy individuals is accompanied by marked biological changes and provide confirmation that CCK-4 is a useful model of panic for research among nonclinical subjects.

Response to flumazenil in women with premenstrual dysphoric disorder

OBJECTIVE

The authors sought to determine whether the administration of flumazenil would induce marked panic symptoms in women suffering from premenstrual dysphoric disorder.

METHOD

Ten women with premenstrual dysphoric disorder and 11 comparison subjects were injected with flumazenil or placebo in a double-blind, randomized, balanced crossover design in a single session in the luteal phase of their menstrual cycles.

RESULTS

Flumazenil induced a much greater panic response in the women with premenstrual dysphoric disorder than in the comparison subjects.

CONCLUSIONS

These preliminary results are consistent with a dysregulation of the g-aminobutyric acid A/benzodiazepine receptor complex during the premenstruum of women suffering from premenstrual dysphoric disorder.

Sensitivity to CCK-4 in women with and without premenstrual dysphoric disorder (PMDD) during their follicular and luteal phases

The authors determined whether women with premenstrual dysphoric disorder (PMDD) exhibit a heightened sensitivity to the panicogenic effects of CCK-4 administration and whether this enhanced sensitivity to CCK-4 would vary with the phase of the menstrual cycle at the time of CCK-4 injection. Twenty-one normal controls and 18 PMDD women were randomly assigned to receive the first and second CCK-4 injection during the follicular phase and the luteal phase or vice versa. PMDD women showed a greater anxiety and panic response to CCK-4. These preliminary results suggest that the CCK-B system may play a role in the pathophysiology of PMDD.

The role of the beta-noradrenergic system in cholecystokinin-tetrapeptide-induced panic symptoms

BACKGROUND

The authors determined whether effective beta-adrenergic blockade could attenuate the panicogenic effects of cholecystokinin-tetrapeptide (CCK-4) in healthy volunteers.

METHODS

Subjects were randomly assigned to either a propranolol (n = 14) or placebo (n = 16) infusion. Ten minutes after completion of the infusion subjects received a bolus injection of CCK-4 (50 micrograms).

RESULTS

Acute pretreatment with propranolol was more effective than placebo in decreasing behavioral and cardiovascular sensitivity.

CONCLUSIONS

These preliminary results suggest that the panicogenic effects of CCK-4 are mediated, in part, through the beta-adrenergic system.