Environmental enrichment reverses proulcerogenic action of social isolation on the gastric mucosa and positively influences pain sensitivity and work capacity.

The aim of the study was to investigate the effects of rat housing conditions-standard conditions, social isolation, environmental enrichment-and the subsequent reversal of these conditions on the vulnerability of the gastric mucosa to ulcerogenic stimuli, somatic pain sensitivity, and treadmill work capacity. Rats, aged 30 days, were placed in standard conditions (SC), social isolation (Is), and environmental enrichment (EE) for 4 weeks. Then half of each group underwent a reversal of housing conditions: SC rats were moved to Is, Is rats were placed in EE, EE rats were moved to Is, for 2 weeks.

Non-Invasive Remote Ischemic Preconditioning May Protect the Gastric Mucosa Against Ischemia-Reperfusion-Induced Injury Through Involvement of Glucocorticoids.

Remote ischemic preconditioning (RIPC) is one of the most effective approaches to attenuate tissue injury caused by severe ischemia-reperfusion (I/R). Experimental studies have demonstrated that RIPC is capable of producing a protective effect not only on heart, but also on brain, lungs, kidneys, liver, intestine, and stomach. We previously demonstrated that glucocorticoids participate in protective effect of local gastric ischemic preconditioning against I/R-induced gastric injury.

Physiological and Pharmacological Effects of Glucocorticoids on the Gastrointestinal Tract.

The review considers the data on the physiological and pharmacological effects of glucocorticoids on the gastric mucosa and focuses on the gastroprotective role of stress-produced glucocorticoids as well as on the transformation of physiological gastroprotective effects of glucocorticoids to pathological proulcerogenic consequences. The results of experimental studies on the re-evaluation of the traditional notion that stress-produced glucocorticoids are ulcerogenic led us to the opposite conclusion suggested that these hormones play an important role in the maintenance of the gastric mucosal integrity. Exogenous glucocorticoids may exert both gastroprotective and proulcerogenic effects.

The peripheral corticotropin-releasing factor (CRF)-induced analgesic effect on somatic pain sensitivity in conscious rats: involving CRF, opioid and glucocorticoid receptors.

The corticotropin-releasing factor (CRF) is involved in somatic pain regulation and may produce an analgesic effect in humans and animals, although the mechanisms of the CRF-induced analgesia remain unclear. CRF action is mediated by the CRF receptors of subtypes 1 and 2 (CRF-R1 and CRF-R2, respectively). Activation of the hypothalamic -pituitary -adrenocortical axis (HPA) is provided by CRF-R1; but CRF-R2 are also involved in the regulation of the HPA axis, and, respectively, glucocorticoids, the end hormones of the HPA axis, also participate in somatic pain regulation.