Hypoxic Pulmonary Vasoconstriction in Humans:Tale or Myth

Hypoxic Pulmonary vasoconstriction (HPV) describes the physiological adaptive process of lungs to preserves systemic oxygenation. It has clinical implications in the development of pulmonary hypertension which impacts on outcomes of patients undergoing cardiothoracic surgery. This review examines both acute and chronic hypoxic vasoconstriction focusing on the distinct clinical implications and highlights the role of calcium and mitochondria in acute versus the role of reactive oxygen species and Rho GTPases in chronic HPV. Furthermore it identifies gaps of knowledge and need for further research in humans to clearly define this phenomenon and the underlying mechanism

Effects of a selective Rho-kinase inhibitor Y-27632 on oxidative stress parameters in acute dichlorvos poisoning in rats.

This study examined the effects of Y-27632, a selective Rho-kinase inhibitor, on organophosphate-induced acute toxicity in rats. Rats were randomly divided into four groups as control (corn oil), dichlorvos (30 mg kg(-1) i.p.), 1 and 10 mg kg(-1) Y-27632 + dichlorvos groups. Cholinergic signs (fatigue, tremor, cyanosis, hyper-secretion, fasciculations) were observed in all the rats in the dichlorvos group and the mortality rate was 50%. No cholinergic findings and deaths were observed in the control and Y-27632 groups. Plasma cholinesterase activities were suppressed with dichlorvos and these reductions were attenuated with Y-27632 pretreatment. There was a marked increase in plasma malondialdehyde level in the dichlorvos group, but Y-27632 pretreatment abolished this elevation. Dichlorvos markedly depressed cardiac paraoxonase activity, but these changes were not markedly modified with Y-27632. Total antioxidant capacities, total oxidant status, oxidative stress index, total free sulfhydryl groups and catalase activities in plasma and cardiac tissues were not markedly different between the groups. No significant changes were observed with cardiac myeloperoxidase activities or plasma arylesterase and ceruloplasmin activities. In conclusion, our results suggest that Rho-kinase pathway is involved in organophosphate intoxication, and a decrease in cardiac paraoxonase activities may play a role in the pathogenesis of acute organophosphate poisoning in rats. Copyright (c) 2008 John Wiley & Sons, Ltd

Oral deltamethrin ingestion due in a suicide attempt

PubMedID: 20568424Deltamethrin intoxication is uncommon throughout the world. The toxicity of insecticides containing pyrethroids is considered relatively lower than that of other insecticides such as compounds containing orga-nophosphate. Acute deltamethrin poisoning due to oral ingestions is relatively rare. This report describes a case of a 32-year-old woman admitted to the emergency department (ED) with irritability, muscle cramps, discomfort, sensation of burning, loss of sensation in her feet and arms and dyspnea due to deltamethrin ingestion. Deltamethrin intoxication should be considered as a differential diagnosis in patients presented to ED with nonspecific neurological symptoms. The supportive treatment in acute phase of intoxication is critical in the management of these patients since higher doses of deltamethrin ingestion may cause severe symptoms