Code, Charles F.

Summary and Conclusions The enhancing effect of adrenalectomy on anaphylaxis in rats has been confirmed. Part of this enhancement is caused by enhancement of the development of sensitivity by adrenalectomy which, however, does not appear to be due to an effect on concentrations of antibodies. Administration of cortisone, just prior to challenging, increased the resistance of adrenalectomized rats to anaphylactic shock although severe reactions still occurred. Administration of cortisone during sensitization of adrenalectomized rats reduced the development of sensitivity so that much milder anaphylactic reactions occurred. Intact of adrenalectomized rats that received injections of cortisone produced slightly lower concentrations of hemolysins when rabbit erythrocytes were injected than similarly treated rats that did not receive cortisone. Administration of cortisone to intact or adrenalectomized rabbits receiving daily intracutaneous injections of antigen lowered greatly the resulting concentrations of circulating antibodies and inhibited the development of cutaneous sensitivity. Adrenalectomy had some enhancing effect on cutaneous sensitivity. Administration of cortisone produced no detectable effect on the concentration of circulating hemolysins produced in guinea pigs after either subcutaneous or intravenous injection of rabbit erythrocytes.

Protection against the effects of headward acceleration afforded by immersion in water has been assayed in the human centrifuge on 15 trained subjects. Immersion in water to the xyphoid afforded an average protection of 1.1 ± 0.1 G for vision and ear opacity and of 1.6 ± 0.2 G for ear pulse and heart rate. Deeper immersion, to the level of the third rib at the sternum increased the protection to 1.8 ± 0.1 G for vision and ear opacity and to 2.8 ± 0.2 G for ear pulse and heart rate. The protection afforded the various physiologic variables increased with the magnitude of acceleration tested. Protection against loss of consciousness may be greater than protection against blackout and is probably similar to the protection afforded the ear pulse and heart rate. The cardiovascular reactions produced by headward acceleration are qualitatively similar with and without water immersion. This finding does not support the concept that impediment to venous return is the primary determinant of man's tolerance to headward acceleration. Visual symptoms occurred at greater amplitudes of ear pulse, and presumably also at greater blood pressures at head level, during water immersion than during control runs. vision; arterial pressure; heart rate; venous return; arterial pulse in ear Submitted on May 13, 1963

The rates of disappearance D2O, Na22/24 and K42 from the arterial blood were determined in 17 dogs following rapid injection of the isotopes into the femoral and portal veins. Differences between systemic and portal venous injections were significant during the early phases of the disappearance of the isotopes (P < 0.05). Systemic insorption was simulated by continuous intravenous injection of D2O, Na22, and K42 at known rates into the femoral vein. The appearance of the isotopes in the arterial blood was determined repeatedly during and after their injection. The rate of injection (simulated insorption) was calculated using the mean systemic arterial disappearance rate. The differences between the calculated and actual rates of injection were insignificant. When portal insorption was simulated by constant injection of the isotope into the portal vein, the calculated rate of injection was not significantly different from the actual rate if the mean portal arterial disappearance curve was used in the calculation. When the systemic arterial disappearance curve was utilized, the calculated rate of injection was slightly faster than the actual rate. Submitted on July 11, 1962

Resting pressure and deglutitive changes of pressure in the gastroesophageal sphincter of 12 healthy subjects were recorded as a tiny balloon-covered pressure transducer and open-tipped tubes connected to transducers were withdrawn through the sphincter by 0.5-cm stages. The pressures—both resting and deglutitive—detected by the balloon unit were of greater magnitude than those recorded by the open-tipped tubes. A reduction in pressure indicating relaxation was the outstanding deglutitive pressure change recorded in the subhiatal portion of the sphincter. In the segment of the sphincter at the hiatus, the subsequent contraction was as prominent as the relaxation. As the units traversed the suprahiatal portion of the sphincteric zone, the reduction of pressure (relaxation) became progressively less and the rise of pressure (contraction) with deglutition became greater. Contraction alone occurred at the points farthest orad. Measurements of time intervals from the start of swallowing in the pharynx indicated a caudad peristaltic progression of both relaxation and contraction through the gastroesophageal sphincteric zone. Submitted on December 21, 1959