CONTACT INFORMATION http://www.loyola.org
Karie Scrogin
Ph.D.
  • Professor
  • Molecular Pharmacology and Therapeutics
Research Keywords
  • Anxiety
Research Summary

Neuroendocrine regulation of circulation in shock, heart failure and anxiety

Our research focuses on the neural control of circulation. More specifically, we study the mechanisms by which the neurotransmitters serotonin and norepinephrine modulate sympathetic control of the cardiovascular system in health and during acute and chronic diseases such as circulatory shock and heart failure. Our recent work has demonstrated that serotonin 5-HT1A receptor agonists act in the brainstem to promote beneficial hemodynamic responses during severe hypovolemia. We are currently pursuing efforts to characterize the neural circuitry involved in this reflex response in the hopes it may one day be exploited to improve treatment for hypovolemic shock. A second focus of the laboratory is to understand the central nervous system mechanisms that contribute to the increased morbidity and mortality observed in patients that develop depression and anxiety following myocardial infarct. To this end, we have developed a rat model of coronary ischemia that displays autonomic abnormalities and anxiety responses that parallel those displayed by human patients with heart failure. Our current efforts are focused on using this model to characterize alternations in adrenergic and serotonergic neurotransmission in brain regions that regulate behavioral and autonomic responses to anxiogenic stimuli, and to determine how chronic treatment with antidepressants influences these pathways. We utilize a number of methods to pursue these aims including telemetric recordings of blood pressure and sympathetic activity as well as brain microdialysis in awake, behaving rats and mice, extracellular recordings from the central nervous system in the rat, neural tract tracing and immunohistochemistry combined with deconvolution microscopy, viral mediated knockdown of targeted proteins in rat and mouse brain, as well as Western Blot and PCR quantification of proteins and message from microdissected brain nuclei.

Publications

Chronic fluoxetine reduces autonomic control of cardiac rhythms in rats with congestive heart failureHenze,M.; Tiniakov,R.; Samarel,A.; Holmes,E.; Scrogin,K.American journal of physiology.Heart and circulatory physiology 2013 ;304(3):H444-54

Sympathetic innervation of the splanchnic region mediates the beneficial hemodynamic effects of 8-OH-DPAT in hemorrhagic shock.Tiniakov,R.; Pahan,K.; Scrogin,K. E.American Journal of Physiology - Regulatory Integrative & Comparative Physiology 2012 ;303(5):R527-38

Serotonin nerve terminals in the dorsomedial medulla facilitate sympathetic and ventilatory responses to hemorrhage and peripheral chemoreflex activation.Kung,L. H.; Scrogin,K. E.American Journal of Physiology - Regulatory Integrative & Comparative Physiology 2011 ;301(5):R1367-79

Serotonin neurons of the caudal raphe nuclei contribute to sympathetic recovery following hypotensive hemorrhage.Kung,L. H.; Glasgow,J.; Ruszaj,A.; Gray,T.; Scrogin,K. E.American Journal of Physiology - Regulatory Integrative & Comparative Physiology 2010 ;298(4):R939-53

The spleen is required for 5-HT1A receptor agonist-mediated increases in mean circulatory filling pressure during hemorrhagic shock in the rat.Tiniakov,R.; Scrogin,K. E.American Journal of Physiology - Regulatory Integrative & Comparative Physiology 2009 ;296(5):R1392-401

Vascular KCNQ potassium channels as novel targets for the control of mesenteric artery constriction by vasopressin, based on studies in single cells, pressurized arteries, and in vivo measurements of mesenteric vascular resistance.Mackie,A. R.; Brueggemann,L. I.; Henderson,K. K.; Shiels,A. J.; Cribbs,L. L.; Scrogin,K. E.; Byron,K. L.Journal of Pharmacology & Experimental Therapeutics 2008 ;325(2):475-483

CRNK gene transfer improves function and reverses the myosin heavy chain isoenzyme switch during post-myocardial infarction left ventricular remodeling.Hart,D. L.; Heidkamp,M. C.; Iyengar,R.; Vijayan,K.; Szotek,E. L.; Barakat,J. A.; Leya,M.; Henze,M.; Scrogin,K.; Henderson,K. K.; Samarel,A. M.Journal of Molecular & Cellular Cardiology 2008 ;45(1):93-105

Hypertensive crisis, catecholamine cardiomyopathy, and death associated with pseudoephedrine use in a patient with pheochromocytoma.Sizemore,G. W.; Scrogin,K. E.; Weisenberg,E. S.; Weldon-Linne,C. M.; Madoo,O. B.Endocrine Practice 2008 ;14(1):93-96

Persistent alterations in heart rate variability, baroreflex sensitivity, and anxiety-like behaviors during development of heart failure in the ratHenze,M.; Hart,D.; Samarel,A.; Barakat,J.; Eckert,L.; Scrogin,K.American Journal of Physiology - Heart & Circulatory Physiology 2008 ;295(1):H29-38

Selective impairment of central mediation of baroreflex in anesthetized young adult Fischer 344 rats after chronic intermittent hypoxia.Gu,H.; Lin,M.; Liu,J.; Gozal,D.; Scrogin,K. E.; Wurster,R.; Chapleau,M. W.; Ma,X.; Cheng,Z. J.American Journal of Physiology - Heart & Circulatory Physiology 2007 ;293(5):H2809-H2818

The 5-hydroxytryptamine1A receptor agonist, (+)-8-hydroxy-2-(di-n-propylamino)-tetralin, increases cardiac output and renal perfusion in rats subjected to hypovolemic shock.Tiniakov,R.; Osei-Owusu,P.; Scrogin,K. E.Journal of Pharmacology & Experimental Therapeutics 2007 ;320(2):811-818

Role of the arterial baroreflex in 5-HT1A receptor agonist-mediated sympathoexcitation following hypotensive hemorrhage.Osei-Owusu,P.; Scrogin,K.American Journal of Physiology - Regulatory Integrative & Comparative Physiology 2006 ;290(5):R1337-44

Influence of short-term versus prolonged cardiopulmonary receptor stimulation on renal and preganglionic adrenal sympathetic nerve activity in rats.Ditting,T.; Hilgers,K. F.; Scrogin,K. E.; Linz,P.; Veelken,R.Basic research in cardiology 2006 ;101(3):223-234

The serotonin 5-Hydroxytryptaphan1A receptor agonist, (+)8-hydroxy-2-(di-n-propylamino)-tetralin, stimulates sympathetic-dependent increases in venous tone during hypovolemic shock.Tiniakov,R.; Scrogin,K. E.Journal of Pharmacology & Experimental Therapeutics 2006 ;319(2):776-782

Mechanosensitive cardiac C-fiber response to changes in left ventricular filling, coronary perfusion pressure, hemorrhage, and volume expansion in rats.Ditting,T.; Hilgers,K. F.; Scrogin,K. E.; Stetter,A.; Linz,P.; Veelken,R.American Journal of Physiology - Heart & Circulatory Physiology 2005 ;288(2):H541-52

5-Hydroxytryptamine 1A receptors in the paraventricular nucleus of the hypothalamus mediate oxytocin and adrenocorticotropin hormone release and some behavioral components of the serotonin syndrome.Osei-Owusu,P.; James,A.; Crane,J.; Scrogin,K. E.Journal of Pharmacology & Experimental Therapeutics 2005 ;313(3):1324-1330

Buspirone raises blood pressure through activation of sympathetic nervous system and by direct activation of alpha1-adrenergic receptors after severe hemorrhage.Osei-Owusu,P.; Scrogin,K. E.Journal of Pharmacology & Experimental Therapeutics 2004 ;309(3):1132-1140

5-HT1A receptor agonist 8-OH-DPAT acts in the hindbrain to reverse the sympatholytic response to severe hemorrhage.Scrogin,K. E.American Journal of Physiology - Regulatory Integrative & Comparative Physiology 2003 ;284(3):R782-91