Physiology Commons^™

Navigating The “Covid Hangover” In Physiology Courses, Jennifer E. Schaefer

Biology Faculty Publications

Undergraduate educators and students must navigate lingering aftereffects of the COVID pandemic on education in the 2021–2022 academic year even as COVID continues to impact delivery of undergraduate science education. This article describes ongoing difficulties for undergraduate science, technology, engineering, and mathematics (STEM) students and educators and suggests strategies and easy-to-use resources that may help educators navigate the “COVID hangover” and ongoing COVID-related disruptions.

The Effects Of Low Dissolved Oxygen Concentrations On Diving Behavior And Lactate Accumulation In Lithobates Pipiens, Benjamin R. Thompson, Tristen M. Zimmerman

Celebrating Scholarship and Creativity Day (2018-)

Dissolved oxygen (DO) concentrations in bodies of water can differ based on geographic location, time of day, or even climate change. Because frogs acquire approximately 20% of their oxygen across the skin, decreases in DO could negatively affect diving behavior by increasing reliance on anaerobic metabolism and formation of lactate. To evaluate this possibility, we measured pulmonary and cutaneous oxygen exchange as well as blood lactate levels before and after a 30-minute dive period under both saturated DO (8.341 ± 0.042 mg/L) and low DO conditions (3.918 ± 0.597 mg/L). Although frogs diving in a low oxygen environment tended to …

Hibernator And Non-Hibernator Responses To Acute Changes In Water Intake, Sydni S. Andruskiewicz

All College Thesis Program, 2016-2019

Hibernating animals undergo dramatic changes in metabolic rates during torpor. One of most notable changes in these animals is the ability to maintain blood pressure and perfuse certain organs. Consequentially, blood perfusion to the kidneys is greatly decreased and the ability to concentrate urine halts. However, about once a week, torpor is interrupted and the animal becomes active to rewarm itself about once a week. This activity induces rapid regeneration of the extracellular osmotic gradient of the kidney, and allows urine to be concentrated. Nonetheless, regaining the extracellular osmotic gradient creates a potentially fatal consequence to the kidney cells. To …

Skeletal Muscle Mass And Composition During Mammalian Hibernation, Clark J. Cotton

Biology Faculty Publications

Hibernation is characterized by prolonged periods of inactivity with concomitantly low nutrient intake, conditions that would typically result in muscle atrophy combined with a loss of oxidative fibers. Yet, hibernators consistently emerge from winter with very little atrophy, frequently accompanied by a slight shift in fiber ratios to more oxidative fiber types. Preservation of muscle morphology is combined with down-regulation of glycolytic pathways and increased reliance on lipid metabolism instead. Furthermore, while rates of protein synthesis are reduced during hibernation, balance is maintained by correspondingly low rates of protein degradation. Proposed mechanisms include a number of signaling pathways and transcription …

Compensatory Review Addressing Acute Ischemic Strokes And Bell's Palsy, Patrick R. Godfrey

Celebrating Scholarship & Creativity Day (2011-2017)

In this study, I review the clinical diagnostic procedure for facial weakness; evaluate the physiological perspective of acute ischemic strokes and Bell's palsy; and assess possible consequences of Tissue Plasminogen Activator (tPA) treatment, and the ramification tPA has on Bell's palsy.

High Altitude Diving In River Otters: Coping With Combined Hypoxic Stresses, Jamie R. Crait, Henry D. Prange, Noah A. Marshall, Henry J. Harlow, Clark Cotton, Merav Ben-David

Biology Faculty Publications

River otters (Lontra canadensis) are highly active, semi-aquatic mammals indigenous to a range of elevations and represent an appropriate model for assessing the physiological responses to diving at altitude. In this study, we performed blood gas analyses and compared blood chemistry of river otters from a high-elevation (2357 m) population at Yellowstone Lake with a sea-level population along the Pacific coast. Comparisons of oxygen dissociation curves (ODC) revealed no significant difference in hemoglobin-oxygen (Hb-O₂) binding affinity between the two populations - potentially because of demands for tissue oxygenation. Instead, high-elevation otters had greater Hb concentrations (18.7 …

Avoidance Of Skeletal Muscle Atrophy In Spontaneous And Facultative Hibernators, Clark Cotton, Henry J. Harlow

Biology Faculty Publications

Smooth and skeletal muscle changes were compared from overwintering white-tailed prairie dogs, spontaneous hibernators that undergo regular, low-temperature torpor bouts, and black-tailed prairie dogs, facultative hibernators that use sporadic, moderate-temperature torpor bouts. The objectives were to assess the abilities of these two species with dramatically different torpor patterns (1) to conserve skeletal muscle morphology, protein, and strength and (2) to use labile protein in the small intestine and liver during the winter season of reduced activity and food intake. Mass and protein concentration of the extensor digitorum longus (EDL), soleus, liver, and small intestine, as well as skeletal muscle strength …

Do Hypothermic Tissue Tolerances Limit Torpor Expression?, Clark J. Cotton, Henry J. Harlow

Biology Faculty Publications

1. Arrest temperatures and Q₁₀ values for extensor digitorum longus (EDL), soleus, trabecula, and jejunum muscle twitch strength, contraction time, and 0.5 relaxation time were calculated for a deep torpor hibernator, white-tailed prairie dog (WTPD) (Cynomys leucurus), a shallow torpor hibernator, black-tailed prairie dog (BTPD) (Cynomys ludovicianus), and a non-hibernator, lab rat (Rattus norvegicus) to test the hypothesis that tissue temperature tolerances limit the depth of expressed torpor.

2. There were no temperature tolerance differences between the tissues of the two species of hibernators. Both hibernating species had arrest temperatures and Q_{10 …}