Organisms Commons^™

Wild Mice With Different Social Network Sizes Vary In Brain Gene Expression, Patricia C. Lopes, Barbara König

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background

Appropriate social interactions influence animal fitness by impacting several processes, such as mating, territory defense, and offspring care. Many studies shedding light on the neurobiological underpinnings of social behavior have focused on nonapeptides (vasopressin, oxytocin, and homologues) and on sexual or parent-offspring interactions. Furthermore, animals have been studied under artificial laboratory conditions, where the consequences of behavioral responses may not be as critical as when expressed under natural environments, therefore obscuring certain physiological responses. We used automated recording of social interactions of wild house mice outside of the breeding season to detect individuals at both tails of a distribution …

Immune-Endocrine Links To Gregariousness In Wild House Mice, Patricia C. Lopes, Esther H. D. Carlitz, Morgan Kindel, Barbara König

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Social interactions are critically important for survival and impact overall-health, but also impose costs on animals, such as exposure to contagious agents. The immune system can play a critical role in modulating social behavior when animals are sick, as has been demonstrated within the context of “sickness behaviors.” Can immune molecules affect or be affected by social interactions even when animals are not sick, therefore serving a role in mediating pathogen exposure? We tested whether markers of immune function in both the blood and the brain are associated with gregariousness, quantified as number of animals interacted with per day. To …

No Evidence For Kin Protection In The Expression Of Sickness Behaviors In House Mice, Patricia C. Lopes, Per Block, Alice Pontiggia, Anna K. Lindholm, Barbara König

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

When infected, animals change their behaviors in several ways, including by decreasing their activity, their food and water intake, and their interest in social interactions. These behavioral alterations are collectively called sickness behaviors and, for several decades, the main hypotheses put forward to explain this phenomenon were that engaging in sickness behaviors facilitated the fever response and improved the likelihood of host survival. However, a new hypothesis was recently proposed suggesting that engaging in sickness behaviors may serve to protect kin. We tested this kin protection hypothesis by combining a field and a laboratory experiment in house mice. In both …

Connecting Model Species To Nature: Predator-Induced Long-Term Sensitization In Aplysia Californica, Maria J. Mason, Amanda J. Watkins, Jordann Wakabayashi, Jennifer Buechler, Christine Pepino, Michelle Brown, William G. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Previous research on sensitization in Aplysia was based entirely on unnatural noxious stimuli, usually electric shock, until our laboratory found that a natural noxious stimulus, a single sublethal lobster attack, causes short-term sensitization. We here extend that finding by demonstrating that multiple lobster attacks induce long-term sensitization (>= 24 h) as well as similar, although not identical, neuronal correlates as observed after electric shock. Together these findings establish long-and short-term sensitization caused by sublethal predator attack as a natural equivalent to sensitization caused by artificial stimuli.

Intermediate Filaments Regulate Tissue Size And Stiffness In The Murine Lens, Douglas S. Fudge, John V. Mccuaig, Shannon Van Stralen, John F. Hess, Huan Wang, Richard T. Mathias, Paul G. Fitzgerald

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

PURPOSE. To define the contributions of the beaded filament (BF), a lens-specific intermediate filament (IF), to lens morphology and biomechanics.

METHODS. Wild-type and congenic CP49 knockout (KO) mice were compared by using electrophysiological, biomechanical, and morphometric approaches, to determine changes that occurred because of the absence of this cytoskeletal structure.

RESULTS. Electrophysiological assessment established that the fiber cells lacking the lens-specific IFs were indistinguishable from wild-type fiber cells. The CP49 KO mice exhibited lower stiffness, and an unexpected higher resilience than the wildtype lenses. The absence of these filaments resulted in lenses that were smaller, and exhibited a higher ratio …

Equal Bmd After Daily Or Triweekly Exercise In Growing Rats, B. D. Kayser, J. K. Godfrey, R. M. Cunningham, R. A. Pierce, S. V. Jaque, Ken D. Sumida

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The purpose of this study was to examine the efficacy of continuous resistance training (3 days/wk) compared to interrupted resistance training where 20-24 h separated an exercise bout (i.e. 6 days/wk) for enhancing bone mineral density (BMD) in growing male rats. The total volume of work performed per week between the two resistance training programs was equivalent by design. Young male rats were randomly divided into Control (Con, n = 9), 3 days/wk resistance trained group (RT3, n = 9), and 6 days/wk resistance trained group (RT6, n = 9). The RT3 and RT6 groups were conditioned to climb a …

Different Training Volumes Yield Equivalent Increases In Bmd, R. A. Pierce, L. C. Lee, C. P. Ahles, S. M. Shdo, S. V. Jaque, Ken D. Sumida

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The purpose of this study was to determine if an exercise threshold existed in stimulating an elevation in bone mineral density (BMD), via resistance training, during the growth period in male rats. 27 male rats were randomly divided into Control (Con, n = 9), 3 ladder climb resistance trained group (3LC, n = 9), and 6 ladder climb resistance trained group (6LC, n = 9). The 3LC and 6LC groups were conditioned to climb a vertical ladder with weights appended to their tail 3 days/wk for a total of 6 wks, but the 6LC group performed significantly more work than …

The Guinea Pig Ileum Lacks The Direct, High-Potency, M2-Muscarinic, Contractile Mechanism Characteristic Of The Mouse Ileum, Michael T. Griffin, Minoru Matsui, Rennolds S. Ostrom, Frederick J. Ehlert

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We explored whether the M2 muscarinic receptor in the guinea pig ileum elicits a highly potent, direct-contractile response, like that from the M3 muscarinic receptor knockout mouse. First, we characterized the irreversible receptor-blocking activity of 4-DAMP mustard in ileum from muscarinic receptor knockout mice to verify its M3 selectivity. Then, we used 4-DAMP mustard to inactivate M3 responses in the guinea pig ileum to attempt to reveal direct, M2 receptor-mediated contractions. The muscarinic agonist, oxotremorine-M, elicited potent contractions in ileum from wild-type, M2 receptor knockout, and M3 receptor knockout mice characterized by negative log EC50 (pEC 50 ) values ± …

Interrupted Resistance Training And Bmd In Growing Rats, J. K. Godfrey, B. D. Kayser, G. V. Gomez, Jason Bennett, S. V. Jaque, Ken D. Sumida

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

A resistance training program, where the exercise was uninterrupted (UT, i.e. continuous repetitions) was compared against another resistance training program where the exercise was interrupted (IT, i.e. 2 exercise sessions during a training day) for enhancing bone modeling and bone mineral density (BMD) in maturating animals. The total volume of work performed between the two resistance training programs was equivalent by design. Young male rats (similar to 8 weeks old) were randomly divided into Control (Con, n = 8), UT (n = 8) and IT (n = 7) resistance trained groups. The UT and IT groups were conditioned to climb …

Resistance Training And Bone Mineral Density During Growth, M. Z. Smith, B. M. Goettsch, R. D. Van Ramshorst, J. A. O'Brien, S. V. Jaque, Ken D. Sumida

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

This study examined the efficacy of two different resistance training programs in enhancing bone modeling and bone mineral density (BMD) in maturating rats. One exercise mode involved lifting a lighter weight with more repetitions (LI), while the other regimen involved lifting a heavier weight with fewer repetitions (HI) where the total volume of work between exercise programs was equivalent by design. Twenty-three male rats were randomly divided into control (Con, n = 8), LI (n = 7), and HI (n = 8) groups. The LI and HI groups were conditioned to climb a vertical ladder with weights appended to their …

Interrupted Vs. Uninterrupted Training On Bmd During Growth, B. M. Goettsch, M. Z. Smith, J. A. O'Brien, G. V. Gomez, S. V. Jaque, Ken D. Sumida

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

This study compared a resistance training program where the exercise was uninterrupted (UT, i.e., continuous repetitions) against a resistance training program where the exercise was interrupted (IT, i.e., 3 exercise sessions during a training day) for enhancing bone modeling and bone mineral density (BMD) in maturating animals. The total volume of work performed between the two resistance training programs was equivalent by design. 24 young male rats were randomly divided into Control (Con, n = 8), UT (n = 8) and IT (n=8) resistance trained groups. The UT and IT groups were conditioned to climb a vertical ladder with weights …