Effect of novel environmental stimuli on rat behaviour and central noradrenaline function measured by in vivo microdialysis

Rationale: Although physically aversive stimuli induce functional changes in central noradrenergic neurones, little is known about the noradrenergic response to environmentally aversive stimuli. Objectives: The first aim was to characterise environmental features that are perceived as stressful by rats. The second was to investigate whether changes in the concentration of extracellular noradrenaline are induced by these environmental features. Methods: A light/dark shuttle-box was used to test rats’ behavioural response to a range of stimuli (novelty, bright light, and the presence of an unfamiliar rat), either before or after microdialysis probe implantation. Changes in the concentration of extracellular noradrenaline in the frontal cortex and hypothalamus in vivo were then evaluated on exposure to these same test conditions. Results: Naive rats spent less time in a brightly-lit test arena than a dark one. However, the behavioural response to the light arena was attenuated by the presence of an unfamiliar rat. Probe implantation intensified the response to the light arena but did not affect behaviour in the dark arena. In the microdialysis studies, there was no change in the concentration of extracellular noradrenaline on transfer of rats to the dark arena but there was an increase in both the frontal cortex (+45%) and hypothalamus (+75%) on exposure to the light arena. A similar increase was induced in both brain regions when the light arena contained an unfamiliar rat. Conclusions: Implantation of a microdialysis probe modifies the behavioural responses to certain environmental stimuli. Regardless of this, the extent to which rats perceive a novel environment as aversive is not the only determinant of the noradrenergic response to such stimuli. However, differences in stimulus controllability in the microdialysis and the behavioural experiments could influence the apparent intensity of the stress. Received: 29 October 1998 / Final version: 19 March 1999     

Effects of mental and physical stress on plasma catecholamine levels before and afterβ-adrenoceptor blocker treatment

Summary In a study in mild hypertensives, the impact of mental and physical stress on plasma epinephrine (E), norepinephrine (NE), and on their ratio (NE/E) was evaluated. The effect of two-adrenoceptor blocking drugs, atenolol and bopindolol, on plasma catecholamine levels was also examined.Each stressful stimulus significantly increased the NE and E levels compared to rest. The increase was progressive from mental stress, through the handgrip test to the treadmill test. A slight decrease in the NE/E ratio was observed following mental stress and the handgrip test, while this ratio increased during the treadmill test.No significant impact of beta blocking treatment on catecholamine levels was observed under any test condition.     

Stoffwechseluntersuchungen unter ergometrischer Belastung bei total duodenopankreatektomierten Patienten

Zusammenfassung Ein Jahr nach totaler Duodenopankmatektomie wurde bei 6 Patienten die exokrine Pankreainsuffizienz geprüft. Diese kann durch orale Gabe von wenigstens 10 g Pankreatin kompensiert werden. Gegenüber 7 Normalpersonen und 6 Typ 1-Diabetikern hatten die Duodenopankreatektomierten unter körperlicher Belastung höhere arterielle Spiegel von Lactat und freiem Glycerin als Ausdruck einer gestörten hepatischen Gluconeogenese bei fehlendem pankreatischem Glucagon. Ihre körperliche Leistungsfähigkeit war auffallend schlecht. Catecholamine stiegen unter körperlicher Belastung nur gering an, Wachstumshormone gar nicht. Diese Resultate sprechen gegen die totale Duodenopankreatektomie als Therapie der chronischen Pankreatitis.

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Metabolic investigations under ergometric strain in patients with total duodenopancreatectomy

Summary One year after total duodenopancreatectomy a clinical and laboratory evaluation including exhaustive bicycle ergometry was performed in 6 male patients. The insufficiency of the exocrine pancreas can be compensated by at least 10 g pankreatin per day. During physical exercise patients had higher arterial values of lactate and free glycerol after duodenopancreatectomy than 7 healthy individuals and 6 diabetic patients type 1. This metabolic overreaction was due to a deficiency of pancreatic glucagon and resulted in an impaired hepatic gluconeogenesis. There was no detectable increase in growth hormones and only a small one in catecholamines. The physical condition of patients after duodenopancreatectomy was clearly worse.

Diese Arbeit ist Herrn Prof. Dr. Dr. h.c. Hans Erhard Bock zum Geburtstag gewidmet     

Effects of support group intervention in postnatally distressed women. A controlled study in Taiwan

Objective: The symptoms of depression experienced by women during the postnatal period may have profound effects on the lifelong health of both the mother and the child. In this randomized controlled study, we systematically evaluated the effects of weekly supportive group meetings for women with postnatal distress. Methods: Sixty postnatally distressed women were randomly assigned to support (n=30) and control (n=30) groups. Women assigned to the support group participated in four supportive group sessions that comprised discussions concerning transition to motherhood, postnatal stress management, communication skills, and life planning. Results: Subjects who attended the support sessions had significantly decreased scores on the Beck Depression Inventory (BDI) and the Perceived Stress Scale (PSS), and significantly increased scores on the Interpersonal Support Evaluation List (ISEL) as evaluated at the end of the fourth weekly session. In contrast, no significant changes were observed in the control group during this period. Conclusion: This is the first controlled study to provide evidence that participation in support groups for postnatally distressed women provides quantifiable psychosocial benefits.     

筋膜悬带对女性压力性尿失禁的治疗作用

目的　对自体阔筋膜作为吊带行尿道悬吊术的疗效和安全性进行分析。方法　 2 0 0 0年 1月至 2 0 0 2年 7月 ,收治 1 3例压力性尿失禁伴子宫脱垂及前后壁膨出患者 ,取自体大腿外侧阔筋膜条作为吊带 ,经下腹阴道联合切口行尿道悬吊带手术 ,同时行阴道式全子宫切除及阴道前后壁修补术。结果　 1 3例患者均获得治愈 ,无阴道出血、感染、排斥反应等并发症发生。 5例患者在术后出现暂时性排尿困难 ,1个月内症状消失。结论　自体阔筋膜带尿道悬吊术是治疗女性压力性尿失禁的安全有效术式。     

Chronic immobilization-induced stress increases plasma testosterone and delays testicular maturation in pubertal rats

We investigated whether chronic stress, applied from prepuberty to early puberty, interferes with the spermatogenic and androgenic testicular functions. Male pubertal rats (40 days old) were immobilized 6 h per day for 15 days. Plasma concentrations of corticosterone, prolactin and testosterone were significantly augmented following immobilization, whereas plasma luteinizing hormone decreased and follicle-stimulating hormone was not altered. Acute immobilization (5 min) increased prolactin and testosterone levels in control rats but caused a significantly higher increase in these hormones when superimposed on chronic stress. A lower extent of testicular maturation was observed in pubertal rats immobilized from prepuberty.     

电针对吗啡成瘾大鼠戒断-复吸行为影响的初步观察

目的 观察针刺对实验动物戒断及复吸期间操作行为的影响。方法 建立大鼠吗啡自身给药模型，随机分模型对照组、绑缚对照组、针刺治疗组。熄灭期(3d)做相应处理，d4吗啡引燃(2mg／kg体重)，观察动物熄灭踏板数(LPE)、复吸踏板数(LPR)。结果 模型对照组观察到典型熄灭-复吸曲线(ERC)；绑缚对照组该曲线发生变异，主要是缩短了熄灭的过程；针刺治疗组彻底改变了熄灭-复吸曲线的形状，使熄灭反跳现象消失，但复吸值变大。以吗啡平台期平均踏板数(ALPP)为基准值，各组间熄灭平均踏板数(ALPE)和复吸踏板数(LPR)无明显差异。结论 相对于自然戒断，针刺及绑缚在熄灭期间均具有较明显的抑制渴求效果，且针刺比绑缚作用更快．效果更明显；短期(3d)的针刺治疗未达到抗短期复吸(d4)效果。更多结果有待后续观察和进一步验证。     

Pain in the newborn, a possible new starting point

Received: 3 May 1996 and in revised form: 15 August 1996 / Accepted: 15 August 1996     

Antioxidant-rich diets improve cerebellar physiology and motor learning in aged rats

The free radical theory of aging predicts that reactive oxygen species are involved in the decline in function associated with aging. The present paper reports that diets supplemented with either spinach, strawberries or blueberries, nutritional sources of antioxidants, reverse age-induced declines in beta-adrenergic receptor function in cerebellar Purkinje neurons measured using electrophysiological techniques. In addition the spinach diet improved learning on a runway motor task, previously shown to be modulated by cerebellar norepinephrine. Motor learning is important for adaptation to changes in the environment and is thus critical for rehabilitation following stroke, spinal cord injury, and the onset of some neurodegenerative diseases. These data are the first to indicate that age-related deficits in motor learning and memory can be reversed with nutritional interventions.     

Glucocorticoids exacerbate insult-induced declines in metabolism in selectively vulnerable hippocampal cell fields

Glucocorticoids (GCs), the adrenal steroids released during stress, can compromise the ability of hippocampal neurons to survive necrotic neurological insults. This GC-induced endangerment has energetic facets, in that it can be attenuated with energy supplementation. In the present report, we studied the effects of GCs on the metabolic response of specific hippocampal cell fields to necrotic insults. We used silicon microphysiometry, which allows indirect measurement of metabolism in real time in tissue explants. Aglycemia caused a significant decline in metabolism in dentate gyrus explants, but not in CA1 or CA3 explants. When coupled with our prior report of cyanide disrupting metabolism only in CA1 explants, and the glutamatergic excitotoxin kainic acid disrupting metabolism only in CA3 explants, this demonstrates that microphysiometry can detect the selective regional vulnerability that characterizes the hippocampal response to these necrotic insults. We then examined the effects of GCs on the response to these insults, monitoring explants taken from rats that were adrenalectomized, intact, or treated with corticosterone (the GC of rats) that produced circulating levels equivalent to those of major stressors. Increased exposure to GCs worsened the decline in metabolism in dentate gyrus explants induced by hypoglycemia, and in CA1 explants induced by cyanide (after eliminating the effects of glial release of lactate for the support of neuronal metabolism). Thus, GCs worsen the metabolic consequences of necrotic insults in hippocampal explants.