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At least 721 records · Page 40Linked to original sources
PubMed1999

[The hypothalamo-hypophyseal-adrenocortical axis: organization, dynamic aspects and the effect of stress on corticotropin-releasing hormone activity in neurons].

Hypothalamic-hypophyseal-adrenocortical (HPA) axis, often termed stress axis, together with the peripheral sympathetic nervous system and the adrenomedullar hormonal system very sensitively and promptly responds to both external and internal stimuli endangering homeostasis. HPA helps to maintain the physiological equilibrium. The HPA axis forms the first line in the protection of the organism, monitoring the negative factors affecting the stability of the organism by responding by secretion of glucocorticoids. The exaggerated activity of HPA axis is harmful for the organism since it induces a number of disorders including hyperlipidemia, muscle atrophy, hypertension etc., not excluding brain damage. The alterations of the HPA axis lead to hypersecretion of glucocorticoids which may play an important role in the pathology of psychical and neurological diseases. (Tab. 3, Fig. 2, Ref. 31.)

Animals↗
PubMed1975

The immature HPO axis.

One cause or anovulation may be an immature hypothalamic-pituitary-ovarian axis. The fact that initial menstrual cycles are usually irregular and often anovulatory implies that a maturation process is taking place in the HPO axis and that cyclic ovulatory menstruation begins only when adequate maturation occurs. Moreover, the external appearance of the ovary of a severely oligomenorrheic or amenorrheic female frequently is similar to that of a prepubertal female--this is, the ovary appears normal in size of slightly smaller, has a smooth, glistening surface without convolutions, and its capsule-like outer surface reveals few, if any, underlying follicles. A reasonable assumption is that there is inadequate gonadotropin stimulation of these ovaries possibly as a result of an immature HPO axis. The studies by radioimmunoassay of FSH and LH levels in prepubertal and pubertal females offer no statistical data by which to measure the maturity of the HPO axis, although consistently low FSH and LH levels may prove meaningful. Studies of FSH and LH in patients exhibiting gonadal dysgenesis neither support or disprove the immature HPO axis theory, but studies of idiopathic sexual precocity tend to support it. Studies using LH-RF in prepubertal and pubertal females indicate a pattern of response which may give useful information in the area.

Adolescent↗
PubMed2001

Effect of "inside-out" and "outside-in" attitude displays on off-axis tracking in pilots and nonpilots.

BACKGROUND: Pilots employing helmet-mounted displays spend sustained periods of time looking off-axis, necessitating the inclusion of attitude symbology on the helmet to maintain spatial awareness. We examined how fundamentally different attitude references, a moving-horizon ("inside-out") or a moving-aircraft ("outside-in"), affected pilot and nonpilot attitude control when looking on- or off-axis. Both a rear-view and a side-view outside-in perspective were depicted to investigate the effect of control-display compatibility. METHODS: Subjects performed a compensatory pitch-roll tracking task either looking on-axis or 90 degrees off-axis using three symbologies: 1) a compressed pitch ladder with horizon line; 2) a 3-D aircraft representation viewed from the rear; and 3) a 3-D aircraft representation viewed from the side. Tracking error in roll and pitch, control bias, and subjective ratings were collected and analyzed. RESULTS: There was no significant difference in the tracking performance of U.S. Air Force pilots in pitch and roll using the inside-out or outside-in rear-view formats on- and off-axis, although they preferred the inside-out format. Nonpilots tracked significantly better using the outside-in rear-view format, which they also preferred. Both groups tracked poorly using the outside-in side-view format and control-display compatibility had no important effect. CONCLUSIONS: Pilots are equally adept using outside-in and inside-out displays. Given that an outside-in display may better reflect a person's inherent frame of reference for orientation (as evidenced by the nonpilots' superior performance with it), the results seem to indicate that pilots, through experience, have adapted to an inside-out frame of reference.

Accommodation, Ocular↗
PubMed2001

Usefulness of long axis M-mode echocardiographic measurements for optimum dialysis in patients on maintenance hemodialysis: comparison with changes in plasma levels of atrial natriuretic peptide and brain natriuretic peptide.

UNLABELLED: It has been suggested that analyzing the left ventricular long axis motion can result in the sensitive detection of cardiac functional disorders. AIM: To evaluate the usefulness of left ventricular long axis indices in managing patients on maintenance hemodialysis. METHODS: Eighteen hemodialysis patients (mean age 51 +/- 10 years) as well as 16 healthy persons (mean age 49 +/- 9 years) were examined. Echocardiograms were recorded, and the plasma concentrations of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) were measured before and after a session of hemodialysis. The following parameters were measured: the left atrial diameter (LAD) and end-diastolic left ventricular diameter (LVDd) from M-mode echocardiograms, the end-diastolic LV volume (LVEDV) and ejection fraction (EF) from 2-D echocardiography, the E/A ratio from transmitral Doppler, the atrial systolic excursion of long axis motion of the mitral ring (ALAM) and maximal lengthening rate of the mitral ring toward the left atrium during the early diastolic phase (MLRe) from LV long axis M-mode echocardiograms. RESULTS: LAD, LVDd, LVEDV, and ALAM showed a positive correlation with plasma levels of ANP and BNP. EF, the E/A ratio, and MLRe showed a negative correlation with plasma levels of ANP and BNP. Changes in ALAM and plasma levels of ANP during hemodialysis were larger in the subgroup of ALAM < or = 0.55 cm before hemodialysis than in the subgroup of ALAM < 0.55 cm before hemodialysis. CONCLUSION: These results indicate that the left ventricular long axis index can detect a disorder of left ventricular diastolic function, and that a hemodialysis patient whose ALAM before hemodialysis is < 0.55 cm is dialyzed with good volume control conditions.

Adult↗
PubMed2001

Influence of pinealectomy and long-term melatonin administration on GH-IGF-I axis function in male rats.

BACKGROUND: A relationship between circadian GH-IGF-I axis activity and pineal gland function in rats is not sufficiently elucidated, particularly in the aspect of melatonin (MEL) participation with relation to a possible mechanism of these dependencies. OBJECTIVE: Influence of pinealectomy and long-term MEL administration on circadian GH-IGF-I axis function in male rats was evaluated. An attempt was also made to determine whether the effect of exogenous MEL is dependent on the pineal gland presence. METHODS: Studies were performed in 192 sexually mature male Wistar rats, which were subjected to pinealectomy or sham operation. In half of the animals from each group MEL (Sigma, USA) in dose of 50 microg/ 100g b.m. was administrated intraperitoneally (daily between 5 and 6 pm during a 4-week period). Blood for RIA assays of MEL, GH and IGF-I concentrations was collected every 3 hours during a day-beginning at 8 am (rats killed by decapitation). RESULTS: Significant influence of pinealectomy and exogenous MEL on a daily profile of endogenous MEL in rats was confirmed. Distinct, dependent on the time of the day anomalies in circadian oscillations of GH and IGF-I showing positive correlation with changes in endogenous MEL concentrations were also shown. GH rhythm was suppressed in a group of rats with removed pineal gland; after pinealectomy distinct decrease and after MEL use - distinct increase of GH and IGF-I concentrations during the day were observed. It had influenced mean daily concentrations and values of amplitude of circadian GH and IGF-I oscillations in all studied groups of animals. In rats with preserved pineal gland the effect of exogenous MEL action was more intensified. CONCLUSIONS: Pineal gland can influence circadian function of GH-IGF-I axis, and in mechanism of this dependence, changes in endogenous MEL concentrations seem to play an important role. Administration of MEL in rats after pinealectomy only partly prevents changes of GH-IGF-I axis function caused by gland removal, which can indicate participation of other pineal gland substances in generating disturbances. Influence of exogenous MEL on GH-IGF-I axis function during the day is dependent on the presence of pineal gland, which can be connected with indirect and/or direct influence of administrated hormone on this gland.

Animals↗
PubMed1979

[Objective evaluation of the cerebral organic-psychiatric axis syndrome--experiences with the encephalopathy questionnaire].

This supplements the publication on "A standardized questionnaire for behavior typical of encephalopathy" (Meyer-Probst, 1978) which dealth with content validation and provisional calibration. The paper is concerned with external validation and, under such headings as "Axis syndrome and milieu factors", "Axis syndrome and school performance" and "Axis syndrome and age", presents the results from questionnaires of an extreme group comparison to illustrate the clinical and diagnostic value of the axis syndrome concept acc. to Göllnitz. Relations of dependence and the usefulness of assessment procedures are discussed, as well as the concept of the axis syndrome in connection with newer trends in specialized psychopathology research.

Brain Damage, Chronic↗
PubMed2000

Vertical facial pattern and orthodontic stability. Part II: Facial axis changes and stability.

Lateral cephalograms and study casts of 55 patients were evaluated to determine if any relationships exist between Facial Axis changes occurring during and after active treatment and either the pretreatment Jarabak Facial Height Quotient or the amount of post-treatment occlusal change, as measured with a weighted PAR score. No significant relationships could be found. There was instead a wide range of individual variation in the post-treatment behaviour of both the Facial Axis and the weighted PAR score, in both the total sample and three Jarabak Facial Height subgroups. Long-term Facial Axis changes occurring in individual patients, however, were not necessarily associated with occlusal deterioration. Since the Facial Axis is likely to change to some extent in the long-term, it was suggested that widely recommended methods for Facial Axis control during treatment should be considered primarily for functional and aesthetic reasons, rather than on the basis of directly ensuring long-term occlusal stability.

Adolescent↗
PubMed2003

[The growth hormone/insulin-like growth factor axis. What is its role in the atherosclerotic process?].

UNLABELLED: GROWTH HORMONE AND ATHEROSCLEROSIS: Adult-onset growth hormone (GH) deficiency is associated with an increase in cardiovascular morbidity and mortality. MECHANISMS: Other than classical risk factors, such as dyslipidemia, a direct interaction between the activity of the GH/IGF-1 axis and the endothelium also plays a part. It is possible that the modulating effect of IGF-1 on nitric oxide (NO) synthesis is also important, together with the anabolic effect on the myocardiocytes. Substitution of recombinant GH induces rapid reduction in the atherosclerotic plaques, suggesting a direct effect of the GH/IGF axis on the atherosclerotic process. In addition to the acquired GH deficiency, as in non-substituted patients following hypophysectomy, attention has recently been focused on the relative GH deficiency as is seen in obesity and in the course of ageing. PERSPECTIVES FOR CARDIOVASCULAR ENDOCRINOLOGY: Therapeutic intervention in the GH/IGF axis might influence the atherosclerotic process. Study of the GH/IGF axis activity and of its correlation with atherosclerosis opens new perspectives in the understanding of the role of this axis in cardiovascular diseases.

Age of Onset↗
PubMed2003

[Influence of interleukin-1 and interleukin-6 on modulation of hypothalamo-pituitary-adrenal axis in pregnancy at term and in spontaneous and oxytocin-induced delivery].

OBJECTIVES: During the pregnancy the placenta and hypothalamus produce trophic hormones for hypothalamo-pituitary-adrenal axis (HPA), i.e. corticotropin releasing hormone (CRH) and adrenocorticotropin (ACTH). The HPA axis of pregnant women is differentially modulated in comparison to non-pregnant ones. Beside steroids, the influence on CRH release may be modulated by cytokines, especially interleukin 1 (IL-1) and interleukin 6 (IL-6). DESIGN: To evaluate the effects of IL-1 and IL-6 on modulation of HPA axis in pregnancy, we have examined the group of women with spontaneous delivery, and second group consists of women delivered after intravenous oxytocin infusion. All women were at term and in the same pregnancy age. MATERIAL AND METHODS: Blood was sampled from a maternal peripheral vein days before labour, during the second stage of labour and on the second postnatal day, the levels of IL-1, IL-6, CRH, ACTH and cortisol were measured. The concentrations of hormones were measured using RIA method. RESULTS: The level of IL-1 before the delivery was significantly higher in the group with oxytocin-induction. CRH concentration before the labour was much higher in the group with spontaneous contractions. The levels of IL-1 and CRH in both groups decreased during the labour and were lowest after the delivery. Concentration of IL-6 did not changed dependently of group and time of blood sampling. Changes in CRH in time concentration did not correlate with changes in ACTH levels. ACTH concentrations were similar in both groups, low before delivery raised during the delivery and low again after labour. Cortisol concentration in spontaneous labour was much lower before delivery in comparison with second examined group, then lowered during and after the delivery. In group with oxytocin induction, cortisol levels raised during the delivery and maintained almost the same level after the labour. The time-changes in IL-1 concentration and ACTH and cortisol levels were similar in shape in group with spontaneous delivery. CONCLUSIONS: These results suggest that IL-6 is not involved in modulation of HPA axis in pregnancy at term. IL-1 may modulate mother's HPA axis, influencing the release of ACTH and cortisol, probably via stimulation of hypothalamic CRH.

Adrenocorticotropic Hormone↗
PubMed2003

Role of the brain-gut axis in alcohol-related gastrointestinal diseases--what can we learn from new animal models?

Ethanol exerts multiple actions on nearly all organs of the body, especially on the central nervous system and the gastrointestinal tract. However, little is known about the effects ethanol has on the brain-gut axis, the linkage between the central neural system and the autonomous innervation of the gastrointestinal tract. It is indisputable that ethanol consumption does affect e.g. exocrine pancreatic secretion or intestinal motility, but it is poorly understood, how alcohol consumption may disturb the brain-gut axis and how this may cause damage to gastrointestinal organs. Due to difficulties in directly assessing ethanol effects on the brain-gut axis in humans, animal models represent a versatile tool to study this topic. However, conventional animal models widely utilized in alcohol research, e.g. the Tsukamoto-French model or the Lieber-DeCarli model, do not mimic the human conditions of ethanol consumption and are therefore not suitable for studies of the brain-gut axis. Established models from other alcohol research disciplines, e.g. addiction research, are by far more applicable. Due to this reason, we have established an animal model of alcohol-dependent rats for the use in gastrointestinal alcohol research. In this model, rats are given free access to different of alcohol solutions (5% and 20% v/v) and tap water. Over time, the rats develop signs of alcohol dependence as seen in humans (e.g. deprivation effect). Organs isolated from rats exposed to this model are currently investigated in our laboratory for alcohol-related gene-regulation compared to non-alcoholic littermates. In addition, non-alcoholic components of alcoholic beverages might affect the brain-gut axis or possibly potentiate the toxicity of ethanol. In our model, commonly ingested alcoholic beverages such as beer, wine, cognac, vodka, and whisky and their non-alcoholic constituents will be tested in future animal studies.

Alcohol Drinking↗
PubMed2004

Maternal and fetal hypothalamo-pituitary-adrenal axis: different response depends upon the mode of parturition.

OBJECTIVES: The changes in corticotropin releasing hormone (CRH), adrenocorticotropin hormone (ACTH), cortisol and dehydroepiandrosterone (DHEA) in maternal and fetal plasma were estimated in two group of women undergoing labour after oxytocin induction, or elective cesarean section to correlate changes in maternal and fetal HPA axis to the different stressor conditions. MATERIALS AND METHODS: Blood was sampled from a maternal peripheral vein two days before labour, during the second stage of labour and on the second postnatal day, and also from umbilical vessels just after delivery. Hormone concentrations were measured by RIA and ELSA methods. The maternal plasma CRH concentration before and after labour was similar in both studied groups. RESULTS: Plasma CRH levels measured before labour in both groups were similar, but during labour after oxytocin infusion declined, and was in group of women with elective cesarean section rose, after the delivery there was no difference between groups. The plasma ACTH prior to the delivery was at the same level in all subjects, during the third stage of labour ACTH rose in the both groups, but was statistically higher in group with oxytocin infusion. The concentrations of cortisol before delivery was similar in both groups, then rose to the same level during the delivery and then declined to the level observed before delivery. The DHEA concentration was similar in both groups, did not change during the labour, there was no difference between its level in the umbilical vein and artery. In the group with oxytocin-induction there was no correlation between maternal CRH and ACTH or cortisol concentration, but such a correlation occurred in the group with elective cesarean section. The concentration of ACTH and DHEA in umbilical artery was similar in both groups but the concentrations of CRH and cortisol in umbilical artery in group of newborns delivered after elective cesarean section were statistically higher. CONCLUSION: The activity of the mother's HPA axis is partially inhibited rather by psychological stressors, than events connected with mode of parturition. The newborn's HPA axis responds in a specific way to mother's HPA-axis. The communication between mother's and newborn's HPA is possibly related to many other factors than placental CRH and ACTH. It is necessary to consider effects of central CRH and ACTH on the fine-tune regulation of HPA axis in the late pregnancy and parturition, not detectable due to the high levels of placental hormones.

Adrenocorticotropic Hormone↗
PubMed2006

[Accuracy of femur mechanical axis in computer-assisted total knee replacement].

The location of the center of the femoral head and the mechanical axis of femur were obtained by using optical tracking localizer in computer-assisted total knee replacement (TKR). The 3-D reconstruction model of femur was used firstly in the accuracy verification of mechanical axis of femur. The results showed that the accurate mechanical axis of femur can be defined by tracking the reference frame pinned at the distal femur. Compared to the intramedullary rods locating, this method introduces mechanical axis error less that 1 and the accuracy and repeatability of mechanical axis definition have been improved greatly.

Arthroplasty, Replacement, Knee↗
PubMed2005

Effects of hypothyroidism and endocrine disruptor-dependent non-thyroidal illness syndrome on the GnRH-gonadotroph axis of the adult male rat.

Effects of primary hypothyroidism (HYPO) on the male gonadal axis are controversial, with only scanty data on the gonadotroph cell response and no information on GnRH tuberoinfundibular neurons, even in animal models. HYPO has been reported to variably induce hypogonadotropic hypogonadism, a hypergonadotropic state, or to have no effects on basal levels of pituitary gonadotropins, both in adult male rats and humans. Similarly, the exogenous administration of GnRH to HYPO rats and humans may increase or decrease gonadotropin secretion. Since inhibitory effects of HYPO on the GnRH-gonadotropin axis are reversed by replacement with L-T4, it has been suggested that thyroid hormone (TH) may regulate tuberoinfundibular GnRH and pituitary gonadotropin biosynthesis and/or secretion. To shed light on this hypothesis, we conducted immunocytochemical studies on the distribution and immunostaining characteristics of hypophysiotropic GnRH neurons, LH, PRL and vasoactive intestinal polypeptide (VIP) immunoreactive (IR) cells in the pituitary of adult, male rats. We show that HYPO reduces IR-GnRH in a restricted population of tuberoinfundibular perikarya and their proximal axons compared to euthyroid controls, but increases IR-VIP both in pituitary cells in direct association with LH-gonadotrophs and within IR-LH cells, itself. We propose that VIP may serve as a juxtacrine/paracrine/autocrine regulator of LH secretion and that, when GnRH biosynthesis is reduced by HYPO, gonadotropin secretion may be rescued by local activating effects of VIP. Polychlorinated biphenyls (PCB), industry toxicants found in food and water, also have inhibitory effects on the gonadal axis, decreasing fertility and suppressing basal and GnRHinduced LH release in male rats. Since PCB may also exert endocrine disruptor-dependent (EDD) effects on the thyroid axis producing a non-thyroidal illness syndrome (NTIS) (coined EDD-NTIS), we developed a rat model of EDD-NTIS to determine whether central hypothyroidism may contribute to the pathophysiology of PCB-induced hypogonadism. On the basis of preliminary animal data, we speculate that one of the mechanisms for Partial Androgen Deficiency of the Aging Male may involve central hypothyroidism and EDD-NTIS, resulting in inhibition of the GnRH-gonadotroph axis.

Animals↗
PubMed2006

[Expanded clavipectoral skin flap combined with reverse axis skin flap in repairing cervical scar contracture deformity after burn].

OBJECTIVE: To evaluate the effect of a combined cervical expanded skin flap in repairing cervical scar contracture deformity after burn injury. METHODS: From April 2001 to May 2003, 16 cases (10 males and 6 females) of scar contracture deformity in the cervix were treated with expanded clavipectoral axis skin flap combined with reverse axis skin flap. The tissue expanders were embedded under the part containing cutaneous branches of transverse cervical artery in cervical segments and the second and/or the third perforating branch of internal thoracic artery for the first operation. Normal saline was injected regularly. The expanded clavipectoral skin flap and reverse axis skin flap with perforating branch of internal thoracic artery were designed, the scar in the cervix was loosed or dissected according to the size of the skin flaps, the skin flaps were transferred to cover the wound, and the contracture deformity in the cervix was corrected. The size of the flaps were 9 cm x 5 cm-15 cm x 7 cm. RESULTS: All skin flap survived. The function and appearance of the cervix was improved significantly after 6-30 months follow-up. However, venous return dysfunction in reverse perforating branch of internal thoracic artery occurred in 1 case, and blood circulation was improved after treatment. CONCLUSION: Expanded clavipectoral axis skin flap combined with reverse axis skin flap can be used to repair scar contracture deformity in cervix, which lessen scar and abate the chance to contract again.

Adolescent↗
PubMedDate not supplied

Optimization of Z-axis automatic exposure control for multidetector row CT evaluation of neck and comparison with fixed tube current technique for image quality and radiation dose.

BACKGROUND AND PURPOSE: Z-axis automatic exposure control (AEC) technique automatically adjusts tube current based on size of body region scanned. The purpose of the current study was to compare diagnostic acceptability, noise, and radiation exposure of multidetector row CT (MDCT) of neck performed with z-axis AEC and with fixed current. MATERIALS AND METHODS: Two study groups of 26 patients each underwent MDCT of neck using z-axis AEC with 8 noise index (NI), 150-440 mA, and 10 NI, 75-440 mA, respectively. A control group consisting of another 26 patients underwent MDCT of neck with fixed-current technique (300 mA). Objective noise and mean tube current-time products (mA . s) were recorded. Two radiologists evaluated images for diagnostic acceptability and subjective noise on a 5-point scale. RESULTS: All CT examinations of study and control groups were diagnostically acceptable, though objective noise was significantly more with z-axis AEC (shoulder: NI 8, 20.6 +/- 6.2 HU; NI 10, 22.2 +/- 4.6 HU) than with fixed current (16.2 +/- 6 HU) (P = .01). There was no significant difference between AEC and fixed current in diagnostic acceptability and subjective noise (P = .22-.42). AEC resulted in significant radiation dose reduction (NI 8, 186.3 +/- 20.5 mA . s; NI 10, 158.1 +/- 21.2 mA x s), compared with fixed current (235 +/- 21.8 mA x s). CONCLUSION: Z-axis AEC resulted in similar subjective noise and diagnostic acceptability, with radiation dose reduction of 21% for NI of 8 and 33% for NI of 10, respectively, for MDCT evaluation of neck, compared with those of fixed current technique.

Adult↗
PubMed1991

Activation of the hypothalamus-pituitary-adrenal axis by cytokines.

Activation of the hypothalamus-pituitary-adrenal axis is among the endocrine changes that occur during the acute-phase response to infection or inflammation. These responses have been ascribed to the release of endogenous cytokines. In the present paper a number of studies on effects of interleukin 1 (IL-1), interleukin 2 (IL-2), interleukin 6 (IL-6) and tumour necrosis factor on the hypothalamus-pituitary-adrenal axis are discussed. In addition some recent data from our laboratory on acute and chronic administration of cytokines are presented. Our data show that continuous infusion of rats with IL-1 elicits a long-term activation of adrenal corticosterone (B) production, suggesting that this peptide is a mediator of the effect of infection or inflammation on the activity of the hypothalamus-pituitary-adrenal axis. Although there is still controversy concerning the site of action of cytokines on the hypothalamus-pituitary-adrenal axis, there is consensus that acutely administered IL-1 increases plasma ACTH and corticosterone levels through activation of hypothalamic CRH neurons. On the other hand, it is possible that during prolonged treatment IL-1 activates the hypothalamus-pituitary-adrenal axis via a rapid effect on hypothalamic CRH neurons and via a delayed effect which results from a direct stimulation of pituitary and/or adrenal cells.

Adrenal Glands↗
PubMed1990

Effects of specific mu and kappa opiate tolerance and abstinence on hypothalamo-pituitary-adrenal axis secretion in the rat.

Chronic administration of opiates to rats results in HPA axis tolerance and abstinence-induced hypersecretion. The effects of specific mu and kappa tolerance and withdrawal on the functional secretion of the HPA axis were evaluated in this study. Adult male rats were injected s.c. twice daily with saline, morphine or U50,488 for 5 days. Serum adrenocorticotrophic hormone (ACTH) or corticosterone (CS) were determined by radioimmunoassay as measures of HPA axis function. Tolerance to morphine (10 mg/kg) and U50,488 (1 mg/kg), but no cross-tolerance, was observed suggesting the development of mu- or kappa-specific tolerance, respectively. Tolerance does not occur at the pituitary or adrenal levels after these paradigms because ACTH and CS responses to exogenous corticotropin-releasing factor and ACTH, respectively, were not attenuated. CS secretion in response to novelty stress was not affected by either chronic opiate treatment, but the circadian variation of CS levels was slightly blunted after chronic morphine. In contrast, the elevation of CS secretion by quipazine (0.5 mg/kg) and physostigmine (0.1 mg/kg) was attenuated after chronic U50,488, but not morphine administration. Both spontaneous and antagonist-precipitated withdrawal from morphine, but not U50,488, resulted in elevation of CS levels. Low doses of morphine suppressed morphine abstinence-induced CS hypersecretion, whereas, U50,488 and clonidine had no effect. In conclusion, alterations of HPA axis function occur during chronic mu or kappa opiate administration that are receptor-specific and involve multiple neural controls of the HPA axis.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗
PubMed1969

The significance of pronounced left axis deviation in the presence of right bundle branch block.

The histories of 117 patients with left axis deviation and complete right bundle branch block (rbbb) on the electrocardiogram were reviewed for evidence of clinical cardiac disease, hypertension or emphysema. One hundred fifty-four patients with complete right bundle branch block alone served as controls. The incidence of coronary artery disease (myocardial infarction or angina) was significantly greater in the group with pronounced left axis deviation; the other factors evaluated showed no significant difference between the two groups. Pronounced left axis deviation of the mean qrs axis is associated with a high prevalence of clinical coronary artery disease. The presence of complete right bundle branch block does not alter their relationship. Some patients with complete rbbb, or with rbbb and pronounced left axis deviation, have no clinical evidence of heart disease.

Aged↗