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Biomedical subjects

D Koszycki

Publications and source records attributed to D Koszycki.

At least 19 recordsLinked to original sources
PubMed2000

Neurohormonal responses to cholecystokinin tetrapeptide: a comparison of younger and older healthy subjects.

We recently found that, compared with younger healthy subjects, older healthy subjects had less symptomatic and cardiovascular response to the panicogenic agent cholecystokinin tetrapeptide (CCK-4). As an exploratory part of that study, we also evaluated the effect of aging on neurohormonal responses to CCK-4. These hormonal data are the focus of this article. Forty healthy volunteers aged 20-35 years and 40 healthy volunteers aged 65-81 years, divided equally between men and women, were compared on their hormonal responses (maximum change from baseline in growth hormone [GH], prolactin, adrenocorticotropic hormone [ACTH], and cortisol) to the intravenous administration of 50 microg of CCK-4 or placebo. Blood samples for serum hormone determination were collected at 2 minutes prior to the intravenous challenge (baseline) and at 2, 5, and 10 minutes after the challenge. In both age groups, maximum increase in prolactin, ACTH and cortisol was significantly greater with CCK-4 than with placebo. Following administration of CCK-4, younger and older groups did not significantly differ in maximum increase in prolactin, ACTH, or cortisol. Older subjects had a statistically significant smaller increase in GH compared with younger subjects but the magnitude of the difference was small and of doubtful clinical relevance. Older subjects who had a panic attack had significantly greater elevations of all hormones compared with those who did not panic and younger panickers had a significantly greater elevation of GH compared with young nonpanickers. For the most part, maximum changes in hormonal levels were not correlated with symptom severity, suggesting that other factors may have contributed to the differential effect of panic on the HPA axis.

Adrenocorticotropic Hormone↗
PubMed2000

A double-blind, placebo-controlled study on the effects of Gotu Kola (Centella asiatica) on acoustic startle response in healthy subjects.

Investigations of the pharmacologic profile of medicinal plants have revealed that a number of plants with purported anxiolytic activity bind to cholecystokinin (CCK) receptors. This finding is intriguing in view of the proposed involvement of CCK in the pathophysiology of fear and anxiety. This double-blind, placebo-controlled study was undertaken to evaluate the anxiolytic activity of Gotu Kola (Centella asiatica) in healthy subjects. Gotu Kola has been used for centuries in Ayurvedic and traditional Chinese medicine to alleviate symptoms of depression and anxiety. Recent studies in the rat have shown that long-term pretreatment with Gotu Kola decreases locomotor activity, enhances elevated-plus maze performance, and attenuates the acoustic startle response (ASR). In this study, the authors evaluated the effects of Gotu Kola on the ASR in humans. Subjects were randomly assigned to receive either a single 12-g orally administered dose of Gotu Kola (N = 20) or placebo (N = 20). The results revealed that compared with placebo, Gotu Kola significantly attenuated the peak ASR amplitude 30 and 60 minutes after treatment. Gotu Kola had no significant effect on self-rated mood, heart rate, or blood pressure. These preliminary findings suggest that Gotu Kola has anxiolytic activity in humans as revealed by the ASR. It remains to be seen whether this herb has therapeutic efficacy in the treatment of anxiety syndromes.

Acoustic Stimulation↗
PubMed1999

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.

Adult↗
PubMed1999

Investigation of cholecystokinin system genes in panic disorder.

There is evidence for the role of the cholecystokinin (CCK) neurotransmitter system in the neurobiology of panic disorder (PD). The CCK receptor agonist, CCK-tetrapeptide (CCK-4) fulfills criteria for a panicogenic agent and there is evidence that PD might be associated with an abnormal function of the CCK system. For example, PD patients show an enhanced sensitivity to CCK-4, and exhibit lower CSF and lymphocyte CCK concentration as compared to healthy controls (reviewed by Bradwejn et al.). Also, untreated PD patients display an increased CCK-4-induced intracellular Ca2+ mobilization in T cells relative to treated PD, depression and schizophrenia. The CCK receptors have been classified into two subtypes: CCK-A and CCK-B. We report here a study of polymorphisms in the CCK pre-pro hormone gene (CCK), CCK-AR, and CCK-BR in DSM-IV panic patients (n = 99) vs controls matched for gender and ethnicity. The CCK polymorphism revealed no association with PD. We identified a new polymorphism for the CCK-A receptor gene, and tested it in our sample, with negative results. A single nucleotide polymorphism has been found in the coding region of the CCK-B receptor gene (CCK-BR) and D Collier (personal communication) identified a highly polymorphic dinucleotide (CT)n microsatellite in the 5' regulatory region. For the CCK-B receptor gene polymorphism, PD patients showed a significant association. Our genetic dissection of the CCK system thus far suggests that the CCK-B receptor gene variation may contribute to the neurobiology of panic disorder.

Alleles↗
PubMed1999

Effects of CCK-4 infusion on the acoustic eye-blink startle and psychophysiological measures in healthy volunteers.

The acoustic startle response (ASR) and a range of psychophysiological parameters were evaluated during a continuous intravenous administration of cholecystokinin-tetrapeptide (CCK-4) in healthy volunteers. Subjects (n=28) were randomly assigned to double-blind infusion of either CCK-4 (0.5 mg/60 min) or placebo. The ASR sessions were performed prior to infusion and at 20 min and 50 min after the onset of infusion by recording eye-blink response to a series of acoustic stimuli (110 dB, 40 ms). An effect of CCK-4 on the eye-blink startle was observed in the first half of infusion. CCK-4 produced an increase of eye-blink startle amplitude from baseline values in contrast to the decrease observed at this time point with placebo. A mild increase in anxiety and heart rate followed by fatigue was reported with CCK-4. Administration of CCK-4 produced increases in plasma concentrations of adrenocorticotropic hormone, cortisol, prolactin and growth hormone. The results of this study show that a prolonged intravenous administration of CCK-4 may be a useful challenge method for further studies on the role of CCK system in the modulation of human anxiety and stress response.

Acoustic Stimulation↗
PubMed1998

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.

Adult↗
PubMed1998

Decrease in short-term memory function induced by CCK-4 in healthy volunteers.

The purpose of this study was to assess the effects of continuous intravenous infusion of the central cholecystokinin (CCK) receptor agonist, CCK-4, on short-term memory and psychomotor performance in healthy volunteers in a double-blind, placebo-controlled, parallel group study. Compared to placebo, CCK-4 (0.5 mg/h) significantly impaired performance on free-recall and recognition of words in the middle of the CCK-4 infusion, but did not affect psychomotor acuity. The results of this study indicate that CCK-4 may exert a negative influence on memory consolidation and retrieval.

Adolescent↗
PubMed1998

MMPI scales for diagnosing acute and chronic PTSD in civilians. Minnesota Multiphasic Personality Inventory.

To develop new Minnesota Multiphasic Personality Inventory (MMPI) scales for diagnosing acute and chronic posttraumatic stress disorder (PTSD), 237 civilians with PTSD or panic disorder (controls) completed the MMPI-R. All 399 items were submitted to chi-square analysis to select those differentiating acute or chronic PTSD from controls. The analyses yielded an MMPI Acute PTSD scale (32 items) and a MMPI Chronic PTSD scale (41 items). Discriminating between acute PTSD and controls, the MMPI Acute PTSD scale had a hit rate of 83% and the MMPI Chronic PTSD scale produced a hit rate of 75% to 80%. Cross-validation produced similar hit rates. These scales scores were not substantially influenced by gender or types of traumatic events, and only the MMPI Acute PTSD scale seemed to not be sensitive to co-morbidity.

Acute Disease↗
PubMed1998

Effects of cholecystokinin tetrapeptide on respiratory function in healthy volunteers.

OBJECTIVE: The authors evaluated respiratory response to cholecystokinin tetrapeptide (CCK-4) in healthy volunteers. METHOD: Subjects were randomly assigned to either a CCK-4 (N = 15) or placebo (N = 15) challenge under double-blind conditions. RESULTS: Dyspnea was reported by all of the subjects who received CCK-4 but only one subject who received placebo. CCK-4 caused a significant increase in tidal volume and minute ventilation but had no effect on breathing frequency. Placebo had no effect on any of the respiratory measures. CONCLUSIONS: These data indicate that the behavioral effects of CCK-4 are accompanied by changes in respiration in healthy volunteers.

Adult↗
PubMed1998

Effect of aging on cholecystokinin-induced panic.

OBJECTIVE: Epidemiologic surveys have found that the incidence and prevalence of panic disorder decline in later life. The goal of this study was to determine whether aging has an effect on healthy subjects' responses to the panicogenic agent cholecystokinin tetrapeptide (CCK-4). METHOD: The study used a double-blind, placebo-controlled design: 40 subjects 20-35 years old and 40 subjects 65 years old or older were randomly assigned to receive an intravenous bolus of either 50 micrograms of CCK-4 or normal saline. RESULTS: When given CCK-4, older subjects had significantly fewer and less intense symptoms of panic, shorter duration of symptoms, and less of an increase in heart rate than did younger subjects. CONCLUSIONS: This study found an age-related change in responsiveness to CCK-4. Further research to delineate the mechanism of this change is warranted.

Adult↗
PubMed1998

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.

Adolescent↗
PubMed1996

Effect of acute tryptophan depletion on behavioral, cardiovascular, and hormonal sensitivity to cholecystokinin-tetrapeptide challenge in healthy volunteers.

Recent data suggest that serotonergic (5-HT) mechanisms may mediate the anxiogenic effects of cholecystokinin (CCK)-related peptides. Accordingly, we investigated the effect of lowering plasma tryptophan to the elicitation of behavioral, cardiovascular, and hormonal changes in healthy volunteers challenged with the tetrapeptide CCK agonist, CCK-4. Forty men without personal or family history of psychiatric disorders were randomly assigned to either a tryptophan-free amino acid mixture, which decreases central 5-HT concentrations, or a control mixture. Five hours after administration of the amino acid mixture, all subjects received a single intravenous injection of CCK-4. The main finding of the study was that acute depletion of tryptophan failed to modify the panicogenic and cardiovascular effects of CCK-4, although it did enhance CCK-4-mediated increases in ACTH/cortisol and prolactin secretion. While these findings suggest that at least part of the neuroendocrine action of CCK-4 is mediated through the 5-HT system, the locus of the 5-HT-CCK interaction and the specific 5-HT receptor subtype involved remains to be determined.

Adolescent↗
PubMed1996

Influence of personality on behavioral response to cholecystokinin-tetrapeptide in patients with panic disorder.

The relationship between personality, as measured by selected clinical scales of the Minnesota Multiphasic Personality Inventory (MMPI) (Hypochondriasis, Depression, Hysteria, Psychasthenia, Social Introversion, and Anxiety) and the Anxiety Sensitivity Index (ASI), and behavioral response to the panicogenic agent cholecystokinin-tetrapeptide (CCK-4) was examined in 29 patients with panic disorder with or without agoraphobia. Significant correlations were found between the MMPI Social Introversion scale and somatic, cognitive, and affective response to CCK-4. Both the MMPI Anxiety scale and the ASI correlated significantly with cognitive response to CCK-4, but not with somatic or affective response. None of the other selected MMPI clinical scales correlated with response to CCK-4. Multiple regression analyses identified the MMPI Social Introversion scale as the best predictor of all three indices of panic-anxiety induced by CCK-4. The results suggest that the relationship between neurotic introversion and sensitivity to CCK requires closer scrutiny.

Adult↗
PubMed1996

MMPI profiles of acute and chronic PTSD in a civilian sample.

In a treatment setting, a group of 165 subjects presenting with either acute or chronic posttraumatic stress disorder (PTSD) were compared to 72 subjects presenting with panic disorder only in order to determine whether the MMPI PTSD assessment strategy developed with Vietnam veterans could be validly used with civilians. Results indicated that the MMPI profile, codetype, diagnostic decision rule, and PK scale developed with samples of Vietnam veterans did not apply well to civilians, especially those presenting with acute PTSD. It is thus recommended that specific assessment strategies be developed for these populations.

Acute Disease↗
PubMed1995

Effect of CI-988 on cholecystokinin tetrapeptide-induced panic symptoms in healthy volunteers.

A randomized, placebo-controlled, double-blind, three-way crossover design was used to evaluate the effectiveness of single oral 100 mg doses of CI-988, a cholecystokinin B (CCKB) antagonist, in attenuating panic symptoms induced by intravenous injection of cholecystokinin-tetrapeptide (CCK-4). Thirty healthy men received the following treatments on three separate occasions: placebo capsules/placebo, placebo capsules/CCK-4, or CI-988 capsules/CCK-4. There was no marked difference in the number, time to onset, or duration of panic symptoms between CI-988/CCK-4 and placebo/CCK-4. There was, however, a 14% difference in sum intensity scores between these treatments that was statistically significant (p = 0.039). The symptoms most affected by CI-988 were cold chills/hot flushes, chest pain/discomfort, and anxiety/fear/apprehension. Panic attack frequency also decreased following CI-988 treatment (8/30 vs. 16/30; p = 0.035). This decrease, amid otherwise modest effects, could be explained by a preferential effect of CI-988 on the subjective experience of anxiety/fear/apprehension. Possible reasons for the relatively modest effects of CI-988 on CCK-4-induced panic symptoms are discussed.

Adult↗
PubMed1994

The panicogenic effects of cholecystokinin-tetrapeptide are antagonized by L-365,260, a central cholecystokinin receptor antagonist, in patients with panic disorder.

BACKGROUND: We investigated whether the selective brain cholecystokinin (CCKB) receptor antagonist, L-365,260, could antagonize the panicogenic effects of CCK-tetrapeptide (CCK-4) in patients with panic disorder. DESIGN: The study employed a double-blind, placebo-controlled, two-period crossover design. Patients (N = 29) received a single oral dose of L-365,260 (10 or 50 mg) or placebo 90 minutes prior to injection of CCK-4. After a 1-week washout period, patients received a different dose of L-365,260 or placebo according to a balanced incomplete block design. RESULTS: The 50-mg dose of L-365,260 was superior to placebo in reducing the number (P < .01) and sum intensity (P < .001) of symptoms induced with CCK-4. Panic attack frequency following CCK-4 injection was 88% for patients receiving placebo, 33% for those receiving the 10-mg dose, and 0% for those receiving the 50-mg dose. The difference between the effects of the 50-mg dose and placebo was statistically significant (P = .002). Increases in heart rate following CCK-4 injection were markedly reduced with both the 50-mg (P < .0001) and 10-mg (P < .01) doses compared with placebo. CONCLUSION: These data suggest that CCKB receptors are an important site of action of exogenous CCK-4. It will be important to determine in future studies the efficacy of CCKB receptor antagonists as antipanic agents.

Administration, Oral↗