Effect of long-term hypoxia on oxygen transport properties of blood in pregnant guinea pigs.
Pregnant guinea pigs undergoing long-term hypoxia were studied and the results compared with those of control animals (pregnant, but non-hypoxic). Hypoxic animals demonstrated a decrease of O2 affinity (-7%) and an increase of O2 capacity (+35%). In addition, the HCT was found to be higher in the hypoxic group (+41%), causing haemorheological disadvantages; in a shear model study the blood of hypoxic animals had to be exposed to the gas compartment of the rheo-oxymeter up to 62% longer than that of the control group. We have postulated, that this rheological impairement is compensated, since no abnormalities in number and abortion rate of fetuses (due to a possible O2 delivery impairment) were found. Our morphological studies in fact support this opinion, showing e.g. more capillary branchings and loops and a reduction of diffusion distances between maternal and fetal blood in hypoxic guinea pig placentae. The results emphasize the importance of more detailed rheological studies in connection with other investigations for a complete description of compensatory mechanisms.
Geisen
C
C
Dept. of Physiology, Medical Faculty, Technical University of Aachen, F.R.G.
Mottaghy
K
K
Scheffen
I
I
Kaufmann
P
P
D000818:Animals; D001693:Biological Transport, Active; D005260:Female; D006168:Guinea Pigs; D006400:Hematocrit; D006454:Hemoglobins / Q000378:metabolism; D000860:Hypoxia / Q000097:blood / Q000150:complications*; D007700:Kinetics; D010092:Oximetry / Q000295:instrumentation; D010100:Oxygen / Q000097:blood*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood*
D006454:Hemoglobins; D010100:Oxygen