Purification and partial characterization of camel (Camelus Dromedarius) ceruloplasmin

Adult and young camel ceruloplasmin (Cp) were isolated and purified using the single-step chromatography on amino ethyl-activated sepharose. There are no differences between the adult and the young camel protein. The molecular mass of the protein, as estimated by SDS-PAGE (denaturant conditions), was approximately 130000 Da. The electrophoretic mobility of camel Cp is slightly higher as compared to human and sheep protein suggesting that the camel Cp is homogeneous, compact and more acid. The copper content was estimated to be 5.8+/-0.3 atoms per molecule. The spectroscopic feature includes an absorption maximum at 610 nm, which could be attributed to type 1 copper. The EPR spectrum was completely devoid of any typical signal of the type 2 copper. The kinetic parameters of the adult camel Cp for the specific activity as p-phenylendiamine oxidase were determined as K(m)=0.42 mM and V(max)=0.93 microM NADH/mn/mg Cp. The optimum pH for the activity was 5.7.     

Influence of halothane on control of breathing in intact and decerebrated cats

The effects of halothane anesthesia have been investigated in intact and in decerebrated cats. Pulmonary ventilation and breathing pattern were studied during room-air breathing, hypercapnia, and O2 inhalation. The following results have been demonstrated. First, halothane anesthesia does not modify pulmonary ventilation, but a tachypnea much more intense in intact than in decerebrated cats is observed. This indicates that halothane-induced tachypnea originates mainly in structures rostral to the brain stem. Second, decerebrated animals exhibit a breathing pattern and a ventilatory response to CO2 similar to those of intact conscious cats, suggesting that forebrain facilitatory and inhibitory influences on brain stem are cancelled out by decerebration. However, the tidal volume vs. inspiratory duration relationship observed in decerebrated cats differs from that in conscious cats. Finally, during halothane anesthesia, ventilatory response to CO2 is markedly depressed. Third, during O2 inhalation, except in decerebrated, anesthetized animals, ventilation is only slightly depressed. This suggests that central stimulatory effect of O2 is enhanced and/or that peripheral chemoreceptor drive is reduced.