NDLI: Regional brain blood flow and cerebral hemispheric oxygen consumption during acute hypoxaemia in the llama fetus

Content Provider	PubMed Central
Author	Llanos, Aníbal J. Riquelme, Raquel A. Sanhueza, Emilia M. Herrera, Emilio Cabello, Gertrudis Giussani, Dino A. Parer, Julian T.
Copyright Year	2002
Abstract	Unlike fetal animals of lowland species, the llama fetus does not increase its cerebral blood flow during an episode of acute hypoxaemia. This study tested the hypothesis that the fetal llama brain maintains cerebral hemispheric O2 consumption by increasing cerebral O2 extraction rather than decreasing cerebral oxygen utilisation during acute hypoxaemia. Six llama fetuses were surgically instrumented under general anaesthesia at 217 days of gestation (term ca 350 days) with vascular and amniotic catheters in order to carry out cardiorespiratory studies. Following a control period of 1 h, the llama fetuses underwent 3 × 20 min episodes of progressive hypoxaemia, induced by maternal inhalational hypoxia. During basal conditions and during each of the 20 min of hypoxaemia, fetal cerebral blood flow was measured with radioactive microspheres, cerebral oxygen extraction was calculated, and fetal cerebral hemispheric O2 consumption was determined by the modified Fick principle. During hypoxaemia, fetal arterial O2 tension and fetal pH decreased progressively from 24 ± 1 to 20 ± 1 Torr and from 7.36 ± 0.01 to 7.33 ± 0.01, respectively, during the first 20 min episode, to 16 ± 1 Torr and 7.25 ± 0.05 during the second 20 min episode and to 14 ± 1 Torr and 7.21 ± 0.04 during the final 20 min episode. Fetal arterial partial pressure of CO2 (P a,C O2 , 42 ± 2 Torr) remained unaltered from baseline throughout the experiment. Fetal cerebral hemispheric blood flow and cerebral hemispheric oxygen extraction were unaltered from baseline during progressive hypoxaemia. In contrast, a progressive fall in fetal cerebral hemispheric oxygen consumption occurred during the hypoxaemic challenge. In conclusion, these data do not support the hypothesis that the fetal llama brain maintains cerebral hemispheric O2 consumption by increasing cerebral hemispheric O2 extraction. Rather, the data show that in the llama fetus, a reduction in cerebral hemispheric metabolism occurs during acute hypoxaemia.
Related Links	http://dx.doi.org/10.1113/jphysiol.2001.013230
Ending Page	983
Page Count	9
Starting Page	975
File Format	PDF
ISSN	00223751
e-ISSN	14697793
Journal	The Journal of Physiology
Issue Number	Pt 3
Volume Number	538
Language	English
Publisher	Blackwell Science Inc
Publisher Date	2002-02-01
Access Restriction	Open
Rights Holder	Blackwell Science Inc
Subject Keyword	Physiology Research in Higher Education
Content Type	Text
Resource Type	Article
Subject	Physiology Sports Science

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in

Adrenergic and vasopressinergic contributions to the cardiovascular response to acute hypoxaemia in the llama fetus

Fetal brain hypometabolism during prolonged hypoxaemia in the llama

An in vivo nitric oxide clamp to investigate the influence of nitric oxide on continuous umbilical blood flow during acute hypoxaemia in the sheep fetus

Regional brain blood flow in man during acute changes in arterial blood gases

Regulation of capillary blood flow and oxygen supply in skeletal muscle in dogs during hypoxaemia.

Cardiovascular and endocrine responses to acute hypoxaemia during and following dexamethasone infusion in the ovine fetus

Enhanced nitric oxide activity offsets peripheral vasoconstriction during acute hypoxaemia via chemoreflex and adrenomedullary actions in the sheep fetus

Regional cerebral blood flow during volitional breathing in man.

Nitric oxide plays a role in the regulation of adrenal blood flow and adrenocorticomedullary functions in the llama fetus

Regional brain blood flow and cerebral hemispheric oxygen consumption during acute hypoxaemia in the llama fetus

Similar Documents

Adrenergic and vasopressinergic contributions to the cardiovascular response to acute hypoxaemia in the llama fetus

Fetal brain hypometabolism during prolonged hypoxaemia in the llama

An in vivo nitric oxide clamp to investigate the influence of nitric oxide on continuous umbilical blood flow during acute hypoxaemia in the sheep fetus

Regional brain blood flow in man during acute changes in arterial blood gases

Regulation of capillary blood flow and oxygen supply in skeletal muscle in dogs during hypoxaemia.

Cardiovascular and endocrine responses to acute hypoxaemia during and following dexamethasone infusion in the ovine fetus

Enhanced nitric oxide activity offsets peripheral vasoconstriction during acute hypoxaemia via chemoreflex and adrenomedullary actions in the sheep fetus

Regional cerebral blood flow during volitional breathing in man.

Nitric oxide plays a role in the regulation of adrenal blood flow and adrenocorticomedullary functions in the llama fetus

Regional brain blood flow and cerebral hemispheric oxygen consumption during acute hypoxaemia in the llama fetus