Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020672 (hypothermia)
 17,327 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The respiratory pathophysiology of A2 influenza infection was studied in mice treated with small-particle aerosols (SPA) of rimantadine or ribavirin. Untreated infections in mice resulted in survival rates of 15% or less and were characterized by (i) severe hypoventilation (decreased P(O2) and increased P(CO2)), (ii) compensated respiratory acidosis (increased P(CO2) and HCO(3) (-), with normal pH), (iii) pneumonia with increased ratio of wet/dry lung weight, and (iv) hypothermia. Treatment with SPA of rimantadine (21 mg/kg per day for 4 days) beginning 72 h after virus challenge significantly improved survival rate (80%) but failed to alter lung pathology from that found in infected, untreated mice. Rimantadine treatment decreased somewhat the severity of hypoventilation, respiratory acidosis, lung wet weight, hypothermia, and lung virus titers from that observed in infected, untreated mice. SPA of ribavirin (26 mg/kg per day for 4 days) initiated 6 h after SPA exposure of mice to virus significantly improved survival rate (95%) and reduced lung virus titers and lung pathology. Gas exchange and pulmonary edema in ribavirin-treated, infected mice were significantly improved over those of infected, untreated controls. The mechanisms for increased survival rates induced by SPA of rimantadine remain uncertain, since increased survival rates could not be ascribed entirely to improvements in lung functions. In contrast, however, ribavirin treatment appeared to improve survival rates by reducing major lung pathology and pulmonary dysfunction. This was probably mediated through the antiviral effects of ribavirin.
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PMID:Effects of small-particle aerosols of rimantadine and ribavirin on arterial blood pH and gas tensions and lung water content of A2 influenza-infected mice. 1 87

Segments of superficial and juxtamedullary proximal convoluted tubules of the rabbit were perfused in vitro to examine the mechanisms responsible for net volume reabsorption. The very early postglomerular segments were not studied. Fluid reabsorptive rates and transepithelial potential differences were compared under various conditions: (a) with perfusate that simulated glomerular filtrate; (b) with perfusate that lacked glucose, amino acids, and acetate and that had HCO(3) and Cl concentrations of 5 and 140 mM, respectively; (c) with perfusate that lacked glucose, amino acids, and acetate but with 20 meq of NaHCO(3) replaced with 20 meq of Na cyclamate; (d) with the same perfusate as in b but in the presence of ouabain in the bath; (e) with ultrafiltrate of rabbit serum titrated with HCl to final HCO(3) and Cl concentrations of 2 and 134 mM, respectively. Tubules were perfused with this titrated ultrafiltrate at 37 degrees C, 21 degrees C, and in the presence of 0.1 mM ouabain in the bath. Bath fluid in all experiments was regular rabbit serum. Under conditions a and b superficial proximal convoluted tubule (SFPCT) and juxtamedullary proximal convoluted tubule (JMPCT) behaved similarly with the exception that SFPCT exhibited a lumen-positive and JMPCT a lumen-negative electrical potential under condition b. However, under condition c SFPCT failed to exhibit net volume reabsorption, whereas reabsorption in JMPCT continued unchanged. Ouabain did not affect volume reabsorption in SFPCT under condition d, whereas neither ouabain nor hypothermia affected SFPCT under condition e. In contrast, ouabain and hypothermia totally inhibited volume reabsorption in JMPCT under conditions d and e. These studies document heterogeneous mechanisms responsible for volume reabsorption in the major portions of SFPCT and JMPCT with passive forces predominating in SFPCT and active forces in JMPCT.
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PMID:Characteristics of volume reabsorption in rabbit superficial and juxtamedullary proximal convoluted tubules. 42 62

The effects of experimentally induced hypothermia on exocrine pancreatic secretion in rabbits were investigated. During hypothermia the flow of pancreatic juice decreased to 50% of basal values and recovered after rewarming. Hypothermia scarcely affected HCO-3, Cl- and Na+ concentrations but did cause significant alterations in K+ concentrations. During hypothermia and later normothermia a parallel secretion in the enzymes amylase, chymotrypsin and trypsin was seen to take place. Enzyme secretion decreased throughout the experimental period in the rabbits undergoing hypothermia and later normothermia, as in the case of the control animals.
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PMID:The effect of hypothermia on exocrine pancreatic secretion in rabbits. 287 Aug 59

Acidification of luminal fluid in the proximal convoluted tubule has been modeled as a pump-leak system. Using isolated perfused rabbit proximal convoluted tubules in a HCO-3/CO2-free in vitro environment, we studied "H+ leak" by imposing pH gradients across the tubule and measuring the change in pH from perfusate to collected fluid. Active acidification was inhibited by acetazolamide with and without hypothermia. At 21 degrees C a symmetrical H+ leak with an apparent permeability coefficient of approximately 0.15 cm X s-1 was found with either a lumen-to-bath or bath-to-lumen [H+] gradient. At 37 degrees C a much higher apparent permeability coefficient was found that was dependent on luminal lactate. Phosphate movement did not affect H+ fluxes significantly. Without luminal lactate, the apparent permeability coefficient was 0.31 cm X s-1. Although this permeability coefficient is larger than other ionic permeability coefficients in this segment, it is not sufficient to account for a significant H+ leak compared with rates of acidification or bicarbonate reabsorption. To investigate the role of Na+-H+ exchange in mediating the observed H+ leak, we perfused tubules with low [Na+] solutions with and without amiloride (10(-3) M). Neither the lower [Na+] nor the presence of amiloride diminished the apparent [H+] permeability coefficient. We conclude that a H+ leak pathway independent of Na+-H+ exchange is present in the proximal convoluted tubule.
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PMID:Hydrogen ion permeability of the rabbit proximal convoluted tubule. 669 75