Effects of repeated restraint stress on gastric motility in rats.
نویسندگان
چکیده
In our daily life, individuals encounter with various types of stress. Accumulation of daily life stress (chronic stress) often causes gastrointestinal symptoms and functional gastrointestinal diseases. Although some can adapt toward chronic stress, the adaptation mechanism against chronic stress remains unknown. Although acute stress delays gastric emptying and alters upper gastrointestinal motility, effects of chronic stress on gastric motility still remain unclear. We investigated the effects of acute (single stress) and chronic (repeated stress for 5 consecutive days) stress on solid gastric emptying and interdigestive gastroduodenal contractions in rats. It is well established that acute restraint stress inhibits solid gastric emptying via central corticotropin-releasing factor (CRF). To investigate whether the sensitivity to CRF is altered following chronic stress, CRF was administered intracisternally. Ghrelin is involved in regulating gastric emptying and upper gastrointestinal motility in rodents. The changes in plasma active ghrelin levels and mRNA expression in the stomach were studied following chronic stress. To evaluate the effects of chronic stress on the hypothalamus-pituitary-adrenal (HPA) axis, plasma corticosterone levels were also measured. Delayed gastric emptying observed in acute stress was completely restored following chronic stress. Acute stress abolished gastric phase III-like contractions, without affecting duodenal phase III-like contractions in the interdigestive state. Impaired gastric phase III-like contractions were also restored following chronic stress. Plasma ghrelin levels and ghrelin mRNA expression were increased significantly after chronic stress. Intracisternal injection of CRF delayed gastric emptying and impaired gastric motility in rats who received chronic stress. Plasma corticosterone concentrations were no more elevated following chronic stress. The restored gastric emptying following chronic stress was antagonized by the administration of ghrelin receptor antagonists. The adaptation mechanism may involve upregulation of ghrelin expression and attenuation of the HPA axis. In contrast, the sensitivity to central CRF remained unaltered following chronic stress in rats.
منابع مشابه
Gastroprotective effect of Alhagi camelorum on experimental gastric ulcer in rats
Introduction: Alhagi camelorum belongs to the Leguminosae family is used in Iranian folk medicine to treat some gastric diseases. The present study was undertaken to evaluate the Alhagi camelorum aqueous extract for anti-ulcer activity in rats. Methods: Male Wistar rats were pretreated with the A. camelorum aqueous extract (150, 300 or 450 mg/kg of B.W., P.O.) before induction of gastric ul...
متن کاملRestraint stress augments postprandial gastric contractions but impairs antropyloric coordination in conscious rats.
Central corticotropin-releasing factor (CRF) plays an important role in mediating restraint stress-induced delayed gastric emptying. However, it is unclear how restraint stress modulates gastric motility to delay gastric emptying. Inasmuch as solid gastric emptying is regulated via antropyloric coordination, we hypothesized that restraint stress impairs antropyloric coordination, resulting in d...
متن کاملEffect of flavonoid quercetin on stress-induced gastric ulcer in rats
Introduction: Mental stress is one of the most important causes of the gastric ulcer. On the other hand, flavonoids such as quercetin show protective effects. The aim of this study was to investigate possible protective effect of quercetin on water restraint stress-induced ulcer in rats. Methods: Adult male Wistar rats were divided into seven groups each containing eight animals. The first g...
متن کاملAdministration of exogenous acylated ghrelin or rikkunshito, an endogenous ghrelin enhancer, improves the decrease in postprandial gastric motility in an acute restraint stress mouse model
BACKGROUND Physical or psychological stress causes functional disorders in the upper gastrointestinal tract. This study aims to elucidate the ameliorating effect of exogenous acylated ghrelin or rikkunshito, a Kampo medicine which acts as a ghrelin enhancer, on gastric dysfunction during acute restraint stress in mice. METHODS Fasted and postprandial motor function of the gastric antrum was w...
متن کاملThe effect of restraint stress in pregnant rats on blood parameters of their offsprings.
Introduction: Stress has many effects on the development of systems and organs in the fetal period, and these effects appear after birth. Since hemopoietic system is susceptible to stress, effects of restraint stress were studied in offspring of pregnant rats. Methods: Pregnant rats were divided into one control and three stress groups. The control group did not receive any stress during th...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- American journal of physiology. Regulatory, integrative and comparative physiology
دوره 296 5 شماره
صفحات -
تاریخ انتشار 2009