The Respiratory Function of the Blood of Urechis Caupo

Kinetic and spectroscopic studies of haemoglobin and myoglobin from Urechis caupo. Distal residue effects

“…Erythrocytes were washed by centrifugation three times at 4°C with 0.15 M-Na2S04/ 10 mM-EDTA and lysed with distilled water, after which the cell ghosts were centrifuged down. Yellow material, described previously as amoeboid cells (Redfield & Florkin, 1931) the haem protein by successive passes of the protein over a Sephadex G-75 column or by (NH4)2SO4 precipitation of the protein according to a method previously described (Brown, 1961). The buffer used throughout was pH 7 phosphate buffer (2 mM-EDTA/0.…”

“…Urechis caupo, an echiuroid worm, lives in U-shaped burrows in sandy mud along the western coast of the United States (Woodward et al, 1928;Redfield & Florkin, 1931) and is commonly referred to as the fat-innkeeper worm on account of its feeding habits. In U. caupo, a relatively large worm, coelomic fluid rich in erythrocytes is moved throughout the length of the body by peristaltic waves, as there is no defined circulatory system (Pritchard & White, 1981).…”

Nonvertebrate Hemoglobins: Functions and Molecular Adaptations

“…Although they have a closed circulatory system, there are no respiratory proteins in the blood, and Hb is found in coelomic cells, coelomic epithelium, body wall muscles, and nerve cord (546). The inter-and subtidal "fat innkeeper worm" Urechis caupo has abundant Hb-containing cells in the coelomic fluid, which has 1.6 -5.0 g Hb/100 ml and an oxygen-carrying capacity of 27-72 ml/l (446). The Hb-containing cells function to transport O 2 to the Mb in the muscles used in burrow ventilations, since the Mb has a higher O 2 affinity than the Hb (439,446).…”

“…The inter-and subtidal "fat innkeeper worm" Urechis caupo has abundant Hb-containing cells in the coelomic fluid, which has 1.6 -5.0 g Hb/100 ml and an oxygen-carrying capacity of 27-72 ml/l (446). The Hb-containing cells function to transport O 2 to the Mb in the muscles used in burrow ventilations, since the Mb has a higher O 2 affinity than the Hb (439,446). The Hb is tetrameric and comprises one major fraction (F-I), which consists of identical chains and two minor ones (F-II and F-III), both of which are heterogeneous, with at least least five components (178).…”

Peristaltic waves of tubicolous worms and the problem of irrigation in Sabella pavonina

“…Fange & Mattison (1961) also attributed a respiratory function to the caudal appendage although Lang (1949) doubted this and found no sign of water currents being produced. It is interesting to note that body dilatations here are associated with oxygen exchange at an inflatable caudal appendage but body constrictions in Urechis are associated with an invaginated respiratory surface-the hind gut (Redfield & Florkin, 1931). According to Lawry (1966) ejection of water from the hind gut may or may not coincide with the arrival of a peristaltic wave of the body wall, but it is not known whether it is correlated with high pressure of the body fluid.…”