The metabolic biochemistry of the wandering shrew (Sorex vagrans)
department or school: Science, Faculty of
department or school: Zoology, Department of
data provider: DSpace
degree campus: UBCV
creator: Emmett, Brian
issued: 2010-03-18T18:30:04Z
issued: 1980
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: The comparative examination of the metabolism of the shrew, Sorex vagrans, at the ultrastructural, mitochondrial and enzymatic level has revealed a number of consistent factors which correlate with the high basal metabolic rate of these mammals. The metabolic picture which emerges is of an organism highly dependent on aerobic metabolism, utilizing lipid or fatty acids as a primary energy source. This appears particularly true for skeletal muscle which, in larger mammals, may be fueled primarily by glycogen and depend more upon anaerobic metabolism at high work loads. Ultrastructural studies reveal that the diaphragm and gastrocnemius muscle are composed of small diameter fibers, associated with an abundance of peripheral and interfibrillar mitochondria. These typical red fibers are considered to operate aerobically, either in a fast or slow twitch fashion. Levels of oxidative (citrate synthase, fumarase β-OH butyrylCoA dehydrogenase) enzymes are elevated with respect to the rat in heart, liver and gastrocnemius muscle while glycolytic enzymes (glycogen phos-phorylase, PK, LDH) are depressed in all tissues but heart which has PK and LDH activities comparable to rat heart. No large differences were observed in the absolute rates or substrate preferences of shrew and rat cardiac mitochondria but enzymatic profiles of these organelles ..show increased activities of citrate synthase and β-OH butyrylCoA dehydrogenase in shrew mitochondria. This may indicate intrinsic differences between shrew and rat cardiac mitochondria, the physiological consequences of which remain to be elucidated. Glycogen is relatively scarce in shrew tissues and, although present in liver, does not form typical mammalian liver α-rosettes. The low levels of phosphorylase in the tissues assayed indicate that the shrew has a reduced ability to metabolize this substrate. In contrast lipid stores appear abundant in all tissues examined. In the gastrocnemius muscle of a series of seven mammals ranging in…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/22095
note: c.l THE METABOLIC BIOCHEMISTRY OF THE WANDERING SHREW (SOREX VAGRANS) by BRIAN EMMETT B. Sc., Dalhousie University, H a l i f a x , 1.97^ A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in the DEPARTMENT OF-ZOOLOGY We accept t h i s t h e s i s as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA October, 1980 i i In p r e s e n t i n g t h i s t h e s i s i n p a r t i a l f u l f i l m e n t o f t h e r e q u i r e m e n t s f o r an a d v a n c e d d e g r e e a t t h e U n i v e r s i t y o f B r i t i s h C o l u m b i a , I a g r e e t h a t t h e L i b r a r y s h a l l make i t f r e e l y a v a i l a b l e f o r r e f e r e n c e and s t u d y . I f u r t h e r a g r e e t h a t p e r m i s s i o n f o r e x t e n s i v e c o p y i n g o f t h i s t h e s i s f o r s c h o l a r l y p u r p o s e s may be g r a n t e d by t h e Head o f my D e p a r t m e n t o r by h i s r e p r e s e n t a t i v e s . I t i s u n d e r s t o o d t h a t c o p y i n g o r p u b l i c a t i o n o f t h i s t h e s i s f o r f i n a n c i a l g a i n s h a l l n o t be a l l o w e d w i t h o u t my w r i t t e n p e r m i s s i o n . D e p a r t m e n t o f The U n i v e r s i t y o f B r i t i s h C o l u m b i a 2075 Wesbrook Place Vancouver, Canada V6T 1W5 D a t e O t 4 ~ H- 11*30 i ABSTRACT The comparative examination of the metabolism of the shrew, Sorex vagrans, at the u l t r a s t r u c t u r a l , mitochondrial and enzymatic l e v e l has re-vealed a number of consistent factors which c o r r e l a t e with the high basal metabolic rate of these mammals. The metabolic p i c t u r e which emerges i s of an organism highly dependent on aerobic metabolism, u t i l i z i n g l i p i d or f a t t y acids as a primary energy source. This appears p a r t i c u l a r l y true for s k e l e t a l muscle which, i n larger mammals, may be fueled p r i m a r i l y by glycogen and depend more upon anaerobic m…
has type: Thesis/Dissertation
is shown at: 10.14288/1.0100263
language: eng
degree discipline: Zoology
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/22095