Gene expression studies advance our understanding of the effects of stress and glucocorticoids on brain function and give a new direction to animal welfare research. In this context, the presence of messenger RNAs (mR...
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Gene expression studies advance our understanding of the effects of stress and glucocorticoids on brain function and give a new direction to animal welfare research. In this context, the presence of messenger RNAs (mRNAs) for corticotrophin releasing hormone (CRH) and vasopressin (vp) in the porcine hypothalamus has recently been documented. This study investigated the expression of CRH, vr and ionotropic glutamate receptor (iGluR) subunit mRNAS in the brains of pigs treated with the synthetic glucocorticoid dexamethasone (Dex 5 mg kg(-1) i.v.). In the hypothalamus, VP, but not CRH, mRNA was reduced 3 hours after Dex. In the hippocampus, expression of mRNAs for some iGluR subunits appeared to he differentially regulated 6 hours after Dex. In addition, CRH message was detected in the hippocampus and significantly upregulated in the CA1 region 3 hours after Dex. The relevance of these findings to stress neurobiology of the growing, pig is discussed. (C) 2000 Harcourt Publishers Ltd.
kappa-Opioid receptor agonists (niravoline) or nonpeptide antidiuretic hormone (ADH) V-2 receptor antagonists (OPC-31260) possess aquaretic activity in cirrhosis;however, there is no information concerning the effects...
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kappa-Opioid receptor agonists (niravoline) or nonpeptide antidiuretic hormone (ADH) V-2 receptor antagonists (OPC-31260) possess aquaretic activity in cirrhosis;however, there is no information concerning the effects induced by the chronic administration of these drugs under this condition. To compare the renal and hormonal effects induced by the long-term oral administration of niravoline, OPC-31260, or vehicle, urine volume, urinary osmolality, sodium excretion, and urinary excretion of aldosterone (ALD) and ADH were measured in basal conditions and for 10 days after the daily oral administration of niravoline, OPC-31260, or vehicle to cirrhotic rats with ascites and water retention. Creatinine clearance, serum osmolality, ADH mRNA expression, and systemic hemodynamics were also measured at the end of the study. Niravoline increased water excretion, peripheral resistance, serum osmolality, and sodium excretion and reduced creatinine clearance, ALD and ADH excretion, and mRNA expression of ADH. OPC-31260 also increased water metabolism and sodium excretion and reduced urinary ALD, although the aquaretic effect was only evident during the first 2 days, and no effects on serum osmolality, renal filtration, and systemic hemodynamics were observed. Therefore, both agents have aquaretic efficacy, but the beneficial therapeutic effects of the long-term oral administration of niravoline are more consistent than those of OPC-37260 in cirrhotic rats with ascites and water retention.
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