A B S T R A C T The effect of lowering the pressure of oxygen from 80 to 34 mm Hg was examined in anesthetized dogs that were undergoing a water diuresis. This degree of hypoxia was associated with an antidiuresis as urine osmolality (Uosm) increased from 107 to 316 mosmol/kg H20 (P < 0.001) and plasma arginine vasopressin increased from 0.06 to 7.5 pLU/ml, (P < 0.05).However, hypoxia was not associated with significant changes in cardiac output (CO, from 4.2 to 4.7 liters/ min), mean arterial pressure (MAP, from 143 to 149 mm Hg), glomerular filtration rate (GFR, from 46 to 42 ml/min), solute excretion rate (SV, from 302 to 297 mosmol/min), or filtration fraction (from 0.26 to 0.27, NS). Hypoxia was associated with an increase in renal vascular resistance (from 0.49 to 0.58 mm Hg/ml per min, P < 0.01). The magnitude of hypoxia-induced antidiuresis was the same in innervated kidneys and denervated kidneys. To further examine the role of vasopressin in this antidiuresis, hypoxia was induced in hypophysectomized animals. The effect of hypoxia on CO, MAP, GFR, SV, and renal blood flow in hypophysectomized animals was the same as in intact animals. In contrast to intact animals, however, hypoxia did not induce a significant antidiuresis in hypophysectomized animals (Uosm from 72 to 82 mosmol/kg H2O). To delineate the afferent pathway for hypoxiastimulated vasopressin release, hypoxia was induced in dogs with either chemo-or baroreceptor denervation. The effect of hypoxia on CO, MAP, GFR, SV, and renal blood flow in the denervated animals was the same as in nondenervated animals. Hypoxia resulted in an antidiuresis in chemoreceptor (Uosm from 113 to 357 mosmol/kg H20, P < 0.001) but not in baroreceptor (Uosm from 116 to 138 mosmol/kg H20, NS) denervated animals. To determine if hypoxia alters renal response to vasopressin, exogenous vasopressin was adminisDr.

No abstract

School-age children, including those with behavioral disorders, are experiencing more stress than ever in the history of public education. Nevertheless, the literature has not addressed the seriousness of stress and how it affects the lives of these children. This article discusses how stress may affect the lives of children with behavior disorders, provides educators with a model for introducing stress management techniques, and closes with strategies for managing stress in the classroom.

excess of either sex in the domestic fowl inherited? Poultry Sci. 11: 20-22. Thornton, E. J., 1944. Possible genetic factors and embryonic mortality in relation to the sex ratio of chicks at hatching. Thesis, Massachusetts State College.

It has been observed in this laboratory( 1 ) , in agreement with published data (2,3), that the vit. B12 in the contents of the ceca of the hen amounts to 6-7 pg per g dry matter. These comparatively high BIZ values are found in the ceca even though the bird is maintained on a B12 deficient diet. The further observation, that long periods of time are required to deplete a hen of B12 when fed a corn-soybean meal type diet, indicates possible absorption of the vitamin from the ceca. This problem was studied by determining; (1) the effect of cecectomy on the rate of depletion of B12 in the egg, and ( 2 ) the absorption of CO-60 labeled vit. B12 from the occluded cecum. For purposes of comparison the absorption of S-35 labeled methionine and sodium sulfate from the cecum was studied under the same conditions.Afethods. Rhode Island Red hens were used in these studies. One group of hens was cecectomized. Following the operation, these birds and a control group were maintained on a vit. B12 deficient diet(4). The rate of depletion of the vitamin in these birds was followed by estimation of the Blz activity of their eggs with Lactobacillus leichmannii( 5) using cyanide in the extraction procedure. The hens used in the second phase of this study were taken off feed approximately 18 hours prior to injection of the radioactive ma-*This project was supported in part by the U. S. Atomic Energy Commission.---terial. Cecal occlusion was accomplished by inserting a small glass rod (15 mm long) through the cloaca into the rectum, the lower intestine being pushed out through a lateral abdominal incision so that the rod could be directed into the cecum. The glass obstruction was then fixed in place in the cecum near the junction of the intestine by loose ties. Following this, the dose was injected into the lumen of the exposed cecum. Two different doses of co-60 labeled vit. B12 were used, one contained 15 pg with an activity of about 0.6 pc, and the other 4 pg with an activity of about 0.9 pc. Solutions containing 0.75 mg of methionine with an activity of approximately 12 JAC or 1 mg of sodium sulfate with an activity of 15 pc were injected. Blood samples were taken by heart puncture. The birds were sacrificed at 24 or 48 hours after injection and the various organs and tissues removed for analysis. In a few instances the kidneys were extracted with pH 4.5 acetate buffer in the presence of cyanide and aliquots taken for chromatography. The solvent system used consisted of acetone containing water ( 5 % VyV) and HC1 (8% V/V) (6). The chromatograms were developed against "no screen" X-ray film for a period of one month. Using this system B12 had an Rf of 0.03 and inorganic cobalt 0.84. Aliquots of the kidney extracts and all other samples, after the addition of cobalt or sulfate carrier were subjected to a complete ash procedure at Karolinska Institutets Universitetsbibliotek on July 12, 2015 ebm.sagepub.com Downloaded from