Birds, hemoglobins

Godovac-Zimmetmann,Kosters,)., Braunitzer, G. Goltenboth, R. (1988). Structural adaptation of bird hemoglobins to high-altitude respiration and the primary sequences of black-headed gull (Lams ridibundus, Charadriiformes) err-... 

Juveniles received a single intravenous injection of 0.2, 2, or 20 mg/kg BW Some deaths in 20 mg/kg group. All survivors from all groups showed hemolytic anemia within 24 h postinjection, recovery beginning within 72 h the 0.2-mg/kg birds also showed reductions in erythrocyte number, hematocrit, and hemoglobin within 24 h (Clarketal. 1988)... 

The amino acid sequences of the two hemoglobins differ by only four substitutions, of which only one is unique among the bird sequences determined so far (65, 66). This is H2a Pro (greylag goose) - Ala (bar-... 

Avian and reptilian counterparts. The erythrocytes of birds and turtles contain a regulatory molecule different from 2,3-BPG. This substance is also effective in reducing the oxygen affinity of human hemoglobin stripped of 2,3-BPG. Which of the following substances would you predict to be most effective in this regard ... 

It seems reasonable to suppose that the elevated cathepsin activity in dystrophic muscle, by enhancing muscle protein breakdown in vivo, is the cause of the increased rate of protein turnover the increased synthesis could then be seen as an adaptive response to the accelerated breakdown. There is yet, however, no real evidence that this is so the factors which control the breakdown of protein in muscle fibers are probably complex and little understood (PIO). A further possibility, that the proteins of atrophying muscles are in some way more susceptible to breakdown by proteolytic enzymes, seems unlikely Kohn (K9) reported that myosin from denervated rat muscle was digested normally by trypsin, and this was found to be true also of myosin from dystrophic mice and chickens (Kl), whereas Pollack and Bird (P21) stated that the autolytic activity of denervated muscle was not increased relative to the breakdown of hemoglobin by the muscle. 

Inositol hexaphosphate is a component of the blood of birds that favors the release of oxygen from hemoglobin by a mechanism similar to that of 2,3-bisphosphoglycerate in other animals. 

Giardina, B., Corda, M., Pellegrini, M.G. Condo, S.G. Brunori, M. (1985). Functional properties of the hemoglobin system of two diving birds (Podiceps nigricollis and Phalacrocorax carbosinensis). Mol. Physiol, 7, 281-92. 

In the case of hemoglobin it is well documented that heme or its precursor, ALA, stimulates hemoglobin synthesis when added to preparations of hemolyzed bird erythrocytes, mammalian reticulocytes, or chick embryo blastoderm [6,7]. 

Blood consists of protein-rich plasma in which the cells or corpuscles are suspended. They are the red and white blood cells (erythroc34 es and leucocytes, respectively) and the platelets (thrombocytes). The red blood cells do not have nuclei and are flexible round or elliptical discs with indented centers. The diameters of red blood cells vary (in pm 4 in goat 6 in pig 10 in whale and up to 50 or more in birds, amphibians, reptiles and fish). Red blood cells contain hemoglobin, the red blood pigment. White blood cells contain nuclei but no pigments, are surrounded by membranes, are 4—14 pm in diameter and are fewer in number than red blood cells. In addition to salts (potassium phosphate, sodium chloride and lesser amounts of Ca-, Mg- and Fe-salts), various proteins, such as albumins, globulins and fibrinogen, are present in blood. 

Boggs DF, Birchard GF. Relationship between hypoxic ventilatory response and hemoglobin 02-affinity in birds. Physiologist 1982 25 325-325. 

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