Metabolic adjustment to temperature in Strongylocentrotus purpuratus (Stimpson) Public Deposited

http://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/1544br688

Descriptions

Attribute NameValues
Creator
Abstract or Summary
  • The metabolism of Strongylocentrotus purpuratus (Stimpson) was investigated at several levels of urchin organization. Some experiments were performed with tissues from recently collected (acclimatized) urchins, Other experiments were performed with tissues from urchins held at one of two temperatures (acclimated) for 30 days. Body-component oxygen consumption was measured for bodywall, gut, testis, and ovary slices from seasonally acclimatized and temperature-acclimated urchins. Metabolic rates of testis and ovary underwent seasonal shifts appearing to compensate for changes in habitat temperature -- i. e., higher and lower rates during cold and warm periods, respectively. Rates of body wall and gut underwent seasonal shifts in a direction opposite those of testis and ovary -- i. e. , inverse compensation. This gonadal-nonreproductive difference was observed less conclusively with temperature-acclimated urchins. Compensatory shifts occurred with testis. Equivocal shifts occurred with body wall, gut, and ovary. Inverse compensation of metabolic rate resulted when oxygen-consumption measurements were repeated with gut slices and homogenates from temperature-acclimated urchins. Radiotracers glucose-1-¹⁴C, glucose-6-¹⁴C, and acetate- 1-¹⁴C -- were incubated with gut, testis, and ovary homogenates from temperature-acclimated urchins. Cold acclimation caused higher CO₂ and lower lipid activities in the testis. Conversely, warm acclimation caused higher CO₂ and lower lipid activities in the gut. Conversion of glucose to CO₂ was greater in gut than in testis. Conversion of acetate to lipid was generally greater in testis than in gut. Phosphogluconate oxidation and lipid synthesis relative to glycolysis and oxidation, respectively, increased in the testis following warm acclimation. Conversely, glycolysis and oxidation relative to phosphogluconate oxidation and lipid synthesis, respectively, increased in the gut following warm acclimation. Cold acclimation resulted in higher levels of glycogenesis for testis and ovary but in equivocal differences for gut. Cytochrome c oxidase activity was determined in gut, testis, and ovary extracts from seasonally acclimatized and temperatureacclimated urchins. Changes in enzyme activity paralleled those in the oxygen-consumption and radiotracer results. Gut activity was highest in September, whereas testis and ovary activities were highest in December and March, respectively. Gut activity was higher following warm acclimation, but testis and ovary activities were higher following cold acclimation. Glucose 6-phosphate dehydrogenase (G6PDH) activity was determined in gut, testis, and ovary extracts from temperature-acclimated urchins. Changes in G6PDH activity were the reverse of those in the oxygen-consumption, radiotracer, and cytochrome c oxidase results, suggesting that changes in the effectiveness with which glycolysis and phosphogluconate oxidation compete for the common substrate, glucose 6-phosphate (G6P), may compensate for each other. Warm acclimation generally increased gonadal G6PDH activity but failed to alter gut activity. Gonadal G6PDH activity was generally much higher than was that of the gut. The apparent G6PDH-G6P affinity for gut, testis, and ovary was increased following cold acclimation. Body-component weights were determined from the urchins used in the metabolic rate-season studies. Gonadal ash-free dry weights expressed as a percentage of the total were maximal in the fall and minimal in the spring, whereas those of the body wall were maximal in the spring and minimal in the fall. Seasonal changes in the gut were negligible by comparison. The above temperature-induced changes in urchin metabolism are discussed relative to temperature-induced changes in whole-urchin metabolism and to situations confronting intertidal populations of urchins. Gonadal catabolism appears maximal in the winter or spring and minimal in the fall, whereas gonadal anabolism appears maximal in the fall and minimal in the spring. Nonreproductive catabolism appears maximal in the fall and minimal in the winter, whereas nonreproductive anabolism appears maximal in the spring and minimal in the fall.
Resource Type
Date Available
Date Copyright
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome) using ScandAll PRO 1.8.1 on a Fi-6770A in PDF format. CVista PdfCompressor 5.0 was used for pdf compression and textual OCR.
Replaces
Additional Information
  • description.provenance : Submitted by Madison Medley (mmscannerosu@gmail.com) on 2013-11-15T19:27:10Z No. of bitstreams: 1 UlbrichtRichardJ1974.pdf: 716979 bytes, checksum: e70c98b2189fd25c61e99a81f9b6729f (MD5)
  • description.provenance : Approved for entry into archive by Kirsten Clark(kcscannerosu@gmail.com) on 2013-11-21T20:37:34Z (GMT) No. of bitstreams: 1 UlbrichtRichardJ1974.pdf: 716979 bytes, checksum: e70c98b2189fd25c61e99a81f9b6729f (MD5)
  • description.provenance : Made available in DSpace on 2013-11-21T20:37:34Z (GMT). No. of bitstreams: 1 UlbrichtRichardJ1974.pdf: 716979 bytes, checksum: e70c98b2189fd25c61e99a81f9b6729f (MD5) Previous issue date: 1973-12-11
  • description.provenance : Approved for entry into archive by Patricia Black(patricia.black@oregonstate.edu) on 2013-11-15T19:32:56Z (GMT) No. of bitstreams: 1 UlbrichtRichardJ1974.pdf: 716979 bytes, checksum: e70c98b2189fd25c61e99a81f9b6729f (MD5)

Relationships

In Administrative Set:
Last modified: 08/07/2017

Downloadable Content

Download PDF
Citations:

EndNote | Zotero | Mendeley

Items