Hypothalamic-pituitary adrenal (HPAA) axis function in adult Fischer-344 rats exposed during development to neurotoxic chemicals perinatally.

The major objective of these experiments was to determine long-term effects on the hypothalamic-pituitary adrenal axis (HPAA) of adult rats exposed during development to chlordecone, an organochlorine insecticide. Chlordecone was administered to mothers prenatally plus the first 12 days of the neonatal period (6 ppm in the diet) or neonatally via a single subcutaneous injection to rats at 4 days of age (1 mg/pup in 20 micrograms of DMSO). DMSO (20 microliters/pup) and dexamethasone (100 micrograms/pup in 20 microliters saline) were also injected on day 4. HPAA function was evaluated at 70-80 days of age. Responsiveness of the HPAA to a repeated stressor was evaluated by exposing rats of each treatment group to a 7-day stress-induced analgesia (SIA) paradigm consisting of a daily 15 sec foot-shock (0.9 mA) exposure which was preceded by a 15 sec white noise conditioned stimulus. The behavioral response to daily stress was evaluated by measuring tail-flick latencies immediately before and/or after each stress exposure. The conditioned response to stress was evaluated 24 hours after the last of 7 daily foot-shock sessions in which rats of each treatment and experimental group were exposed to the shock chamber only. All rats were killed 15 minutes after the final session and tissue (serum and adrenals) were removed and frozen for later chemical analysis; serum and adrenal corticosterone (CS) and serum prolactin (Prl) levels were measured. Perinatal exposure to chlordecone did not significantly alter the behavioral and/or neuroendocrine responses to stress. Ambient hormone levels (both CS and Prl), however, were uniformly attenuated by chlordecone.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcohol and ischemic heart disease: a review.

Evidence from epidemiological studies suggests that consumption of alcohol at moderate levels might be protective against IHD. The alcohol-IHD relationship appears to be U-shaped, so that the risk of IHD associated with moderate levels of alcohol consumption is lower than that for abstainers and heavy drinkers. However, the effects of alcohol upon the risk of IHD must be examined in the context of its overall effects upon health. When this is done, the potential benefits are not clear-cut. This paper reviews the epidemiological evidence relating to the alcohol-IHD association, considers the mechanisms by which alcohol might exert its effects upon IHD risk, and suggests some avenues for future research in this area.

Antistress and antifatigue properties of Panax ginseng: comparison with piracetam.

The antistress and antifatigue properties of a Chinese ginseng preparation were tested on Swiss albino mice, exposed to various experimental models of stress, and were compared with those of piracetam. Both ginseng and piracetam were administered chronically in drinking water for 16-18 days as well as acutely, by injection, 30-60 min prior to the experiments. Reactivity of the mice, loss in body weight, amount of faeces, length of endurance and incidence of mortality were graded and measured. Both piracetam and ginseng treatment provided good protection against electroshock stress when compared to the untreated mice; fighting scores, incidence of tonic convulsion and mortality were significantly less in the treated groups. In the heat stress experiments, both piracetam and ginseng provided significant protection to the treated mice against exposure to heat. In the fatigue stress of forced swim test, ginseng treatment provided effective adaptation to fatigue and increased endurance in both male and female mice; piracetam showed some antifatigue effects on the male mice only. In the locomotor activity tests, ginseng did not depress motility, while piracetam did so in the later part of the tests. These results are discussed in the light of the antistress properties of the drugs as reported in the literature.

Anxiety, anger, and neurogenic tone at rest and in stress in patients with primary hypertension.

To determine whether basal blood pressure or pressor responses to stress are related to sympathetic nerve tone or to psychological factors in hypertensives, 15 hypertensives and 13 normotensives were studied by mean of a self-administered questionnaire, isometric handgrip exercise (IHE), and the mental stress of serial subtraction. Plasma norepinephrine (NE), epinephrine (E), blood pressure (BP) and heart rate (HR) were measured before and at the end of IHE and mental stress. A greater number of hypertensives had suppressed anger (p less than 0.01) and scored higher on anxiety trait (p less than 0.01) and depression (p less than 0.05). Prestress (IHE and mental) BP and NE values were significantly greater in hypertensives (all p less than 0.01). During IHE, both groups had a significant increase of BP, HR, and NE (all p less than 0.01) but E rose in hypertensives only (p less than 0.05). The percentage change of BP, HR, NE, and E during IHE was similar in both groups. The changes of BP and HR were not related to NE or E. During mental stress, HR (p less than 0.01) and E (p less than 0.05) increased in both groups. However, BP (systolic and diastolic) increased in normotensives only (p less than 0.01). Plasma NE contents were unchanged in both groups. There were significant positive correlations of anxiety trait with systolic BP (p less than 0.05), diastolic BP (p less than 0.05), and NE (p less than 0.05) and E (p less than 0.05). Although hypertensives had increased neurogenic tone related perhaps to inward anger and anxiety, the percentage responses of neurogenic tone and BP to IHE were equivalent to those of normotensives. The challenge of serial subtraction did not elicit further noradrenergic or pressor responses in hypertensives. Suppressed anger and anxiety, via increased basal neurogenic tone, may be pathogenic factors in some patients with primary hypertension.

[Hemodynamics in patients suffering from hyperkinetic cardiac syndromes and in normal persons under psychological stress before and after treatment with propranolol (author's transl)]. / Hämodynamische Veränderungen bei Patienten mit hyperkinetischem Herzsyndrom und bei Normalpersonen unter psychischem Stress vor und nach Beta Rezeptoren-Blockade mit Propranolol.

In patients with hyperkinetic heart syndrome we found at rest a higher heart rate, a higher stroke volume and a higher cardiac output than in normal volunteers. Therefore blood pressure is high although peripheral resistance is lower than in normals. Similar circulatory differences were found under conditions of mental stress. After beta-adrenergic blockade with 15 mg Propranolol heart rate and cardiac output decrease, whereas peripheral resistance increases. Mean blood pressure thus remains unchanged. Even after beta-adrenergic blockade circulatory differences between normals and patients with hyperkinetic heart syndrome are seen. The possible causes of these differences are discussed.

Psychic distress, life crisis, and use of psychotherapeutic medications: national household survey data.

Findings are reported from a nationwide survey of a cross-section probability sample (N = 2,552) of US adults. Data on psychic distress were obtained from a shortened version of the Hopkins symptom checklist, data on life crises from a shortened version of the Holmes-Rahe social readjustment rating scale. Methods for collecting data on use of psychotherapeutic medications were validated in a separate study. Data are presented on the prevalence of high levels of psychic distress and life crisis among various age, sex, and other demographic subgroups; on the relation between life crisis and psychic distress; and on the relation of life crisis and psychic distress to use of psychotherapeutic medications and alcohol. The findings suggest an illness behavior model for the use of psychotherapeutic medications in outpatient practice, and the lend little support to a "self-indulgent consumer" interpretation.

[Endorphins--endogenous peptides with morphine-like effects. 2. Biological importance, clinical apsects]. / Endorphine--körpereigene Peptide mit Morphin-ähnlicher Wirkung. Teil 2: Biologische Bedeutung, klinische Gesichtspunkte.

Since 1974 peptides with opiate-like action both in vivo and in vitro have been isolated from the nervous system of various vertebrates and man. The localization of these peptides (endorphins) within the central and peripheral nervous system reflects the possible biological functions in which they may participate: the response of the CNS to painful stimuli (dorsal horn of the spinal cord, central grey matter, thalamus); the control of emotions (limbic system); the regulation of vegetative functions (medulla oblongata); the response of the body to stress the control of endocrine function (hypothalamus, infundibulum, hypophysis); the control of extrapyramidal motor activity (brain stem) or the control of intestinal motility (intramural nervous plexus). Up-to-date knowledge suggests that the endorphins may function as neurotransmitters, neuromodulators or hormones and that such functions vary according to the special sites of synthesis, storage and action of these various peptides within the body.

[Modulation of autonomic correlates of emotional stress and adaptive responses]. / Moduliatsiia vegetativnykh korreliatov émotsional'nogo stressa i adaptatsionnykh reaktsii.

The character and dynamics of the cardio-vascular response to psychogenic stress (confrontation of cat and dog) depends on active or passive type of behavioral response. Tranquilizers inhibit long-lasting hypertension otherwise occurring after the stress stimulus. Adaptive cardio-vascular responses and baroreceptor reflexes did not alter after tranquilizers administration. Effects of psychotropic drugs correspond to the type of individual behavioral response.

Effect of alcohol on emotional responses to stress.

When participating in tasks involving various probabilities of receiving an electric shock, men who had previously drunk alcohol maintained high levels of anxiety while anxiety decreased in men who had previously drunk a placebo.

[Myocardial energy metabolic disorders in emotional-pain stress and the prevention of these disorders by using sodium gamma-oxybutyrate]. / Narusheniia énergeticheskogo metabolizma miokarda pri émotsional'no-bolevom stresse i profilaktika étikh narushenii s pomoshch'iu gamma-oksibutirata natriia.

Marked disorders of energy metabolism in the heart muscle simultaneously with the development of ulcerous lesions of the stomach were revealed in animals which had suffered an emotional-pain stress (EPS). These disorders are displayed in the fact that two hours after EPS, the glycogen reserve in the animal's myocardium diminishes, resynthesis of glycogen and oxidation of the main substrates of the tricarboxylic acid cycle are inhibited, and malate dehydrogenase and possibly other dehydrogenase systems of the mitochondria are partly inactivated. Such decrease in the activity of the metabolic tracts is attended by depression of the force and rate of cardiac contractions revealed on inducing a high rate of contractions. The preliminary administration of sodium gammaoxybutyrate to a considerable extent prevents all the changes in the animal's myocardium occurring due to the effect of EPS.

Effects of antianxiety drug and personality on stress-inducing psychomotor performance test.

The present study was carried out to clarify the effects of an antianxiety drug and of personality characteristics on a psychomotor performance test. Forty-eight healthy women college students were chosen from 64 volunteers as having either high or low levels of trait anxiety, neuroticism, or extroversion. Subjects with high trait anxiety and/or neuroticism tended to show a decrease in both speed and accuracy of the mirror drawing test (MDT) in the initial nondrug trials. Bromazepam, 5 mg, a benzodiazepine derivative, decreased this decrement in highly anxious subjects but worsened the speed in less anxious subjects. The personality traits of subjects, as well as the degree to which a performance test will induce stress, must be considered when evaluating the effects of antianxiety drugs on the performance of normal volunteers. The clinical anxiety-reducing efficacy of drugs may be predicted by using the MDT in subjects with high levels of anxiety and/or neuroticism.

The effects of psychological stress and vagal stimulation with morphine on vulnerability to ventricular fibrillation (VF) in the conscious dog.

Ventricular vulnerability to fibrillation was assessed in 12 conscious dogs in aversive and nonaversive environments using the repetitive extrasystole (RE) threshold method. In the average environment, RE threshold was 45 per cent lower than in the nonaversive setting and heart rate and blood pressure were significantly elevated. This decrease in RE threshold occurred within 10 minutes of exposing the animals to stress. In contrast, the recovery in RE threshold in the nonaversive setting occurred over a 40 minute period. When morphine sulfate (MS) 0.25 mg./Kg was administered to dogs in the aversive environment, the RE threshold was significantly increased. Cholinergic blockade of vagal efferent activity with atropine (0.2 mg./Kg) annulled partially the effect of MS on RE threshold MS was without effect in the nonaversive environment. It is concluded that MS exerts a significant protective effect on increased ventricular vulnerability associated with psychological stress. This effect is mediated by the vagotonic and sedative actions of morphine.

[Psychophysiologic characteristics of the individual psychotropic activity of benzodiazepine derivatives under experimental conditions]. / Psikhofiziologicheskaia kharakteristika individual'noi psikhotropnoi aktivnosti benzodiazepinovykh proizvodnykh v usloviiakh éksperimenta.

In 156 experiments performed on 41 cats with adequate experimental models of pseudoneurotic conditions, states of anxiety due to an electrostimulation of the hypothalamus through implanted electrodes and an emotional stress due to a conflict situation the authors compared the individual traits of the psychotropic activity of lorazepam, diazepam, chlordiazepoxide, oxazepam, nirazepam. These experiments permitted to display significant differences of psychophysiological structures in the tranquilizing effect of 5 benzodiazepine derivatives.