title: Temperature and cerebral blood flow regulation in the freshwater turtle, Pseudemys scripta.
abstract: Chemical regulation of cerebral blood flow (CBF) by CO2 has been demonstrated in an ectohermic vertebrate (Davies, Am. J. Physiol. 260: R382, 1991). Cerebrovascular sensitivity to CO2 (delta CBF/delta PaCO2), a measure of the vascular reactivity of the cerebral blood vessels to CO2, was found to be 0.7 ml.min-1.100 g-1.Torr-1 during normoxia and 3.4 during anoxia in the freshwater turtle, Pseudemys scripta. In the present study, the effect of body temperature on delta CBF/delta PaCO2 was studied. delta CBF/delta PaCO2 was not significantly affected by body temperature. It was concluded that if delta CBF/delta PaCO2 remains constant with changes in body temperatures and CBF is controlled by CO2, CBF should increase with temperature due to the temperature-induced increase in PaCO2.
authors.affiliation: Department of Physiology, Texas Tech University Health Sciences Center, School of Medicine, Lubbock 79430.
authors.forename: D G
authors.initials: DG
authors.lastname: Davies
mesh_terms: D000136:Acid-Base Equilibrium / Q000502:physiology; D000818:Animals; D001784:Blood Gas Analysis; D001831:Body Temperature / Q000502:physiology*; D002245:Carbon Dioxide / Q000097:blood; D002560:Cerebrovascular Circulation / Q000502:physiology*; D000860:Hypoxia / Q000097:blood; D008863:Microspheres; D014426:Turtles / Q000378:metabolism*
chemical_list: D002245:Carbon Dioxide