Measurement of Panic‐Like Responses Following Intravenous Infusion of Sodium Lactate in Panic‐Prone Rats

Tammy J. Sajdyk1, Stanley R. Keim1, Shelley R. Thielen1, Stephanie D. Fitz1, Anantha Shekhar1

1 Indiana University Medical Center, Indianapolis, Indiana
Publication Name:  Current Protocols in Neuroscience
Unit Number:  Unit 9.17
DOI:  10.1002/0471142301.ns0917s24
Online Posting Date:  November, 2003
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Abstract

This unit describes a putative animal model for panic disorder. The basic premise is that pharmacological disruption of critical brain regions implicated in the circuitry of anxiety will lead to a condition similar to that of the human disorder. A clinically relevant test, the sodium lactate challenge, is utilized to assess parallels between the human condition and this rat model.

Keywords: Amygdala; anxiety; CRF; GABA; hypothalamus; panic; social interaction; sodium lactate; stress

     
 
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Table of Contents

  • Basic Protocol 1: Priming of Anxiety in Rats by Administration of Urocortin in the Basolateral Nucleus of the Amygdala
  • Alternate Protocol 1: Lactate Challenge in Bicuculline Methiodide–Primed Rats
  • Basic Protocol 2: Developing Panic‐Prone State in Rats by Administration of L‐Allylglycine in the Dorsomedial Hypothalamus
  • Support Protocol 1: Behavioral Assessment of Rats in the Social Interaction Test
  • Commentary
  • Literature Cited
  • Figures
     
 
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Materials

Basic Protocol 1: Priming of Anxiety in Rats by Administration of Urocortin in the Basolateral Nucleus of the Amygdala

  Materials
  • Heparin
  • 0.9% (w/v) NaCl (sterile saline)
  • Acetone
  • Cidex
  • Male Wistar rats (250 to 300 g), singly housed (Harlan Sprague‐Dawley)
  • 99.9% isoflurane
  • Betadine
  • Alcohol pads
  • Lidocaine
  • Racellets: hemostatic cotton pellets with epinephrine
  • Cranioplastic cement (liquid and powder)
  • Buprenex
  • 0.05 N sodium lactate solution
  • Urocortin in 1% BSA
  • Bovine serum albumin (BSA), optional
  • India ink
  • 0.01‐ and 0.02‐in. Tygon tubing
  • 26‐G guide cannulae (10‐mm length; Plastic Products)
  • Surgical tools:
    • Scalpel
    • Large blunt‐tipped scissors
    • Small pointed scissors
    • Vannas
    • Small and large trocars
    • Curved forceps
    • Vessel cannulation forceps
    • Mosquito hemostats
    • Needle holder
  • Telemetric probe (PXT 50; Data Sciences)
  • Gas anesthetic machine:
    • Anesthetic cone mask
    • Gas anesthetic regulator
    • Plexiglas anesthetic induction chamber
  • Animal balance (accurate to 1 g)
  • Electric shaver
  • Thermoblanket with electric source
  • Rectal probe
  • Surgical tape
  • Sterile surgical drape
  • 1‐ and 5‐ml syringes, sterile
  • 23‐G needle
  • Sterile suture 4.0
  • Sterile gauze
  • Plastic hemostats
  • Straight pins
  • AM/FM radio
  • Telemetric magnet
  • Telemetric probe (PXT 50; Data Sciences)
  • Sterile 3.0 suture with ½‐in. tapered needle
  • Small animal stereotaxic instrument (dual arms)
  • Anesthetic mask for incisor bar
  • Cauterizer
  • Dremel with no. 105 tip
  • 2.4‐mm screws (Plastic Products)
  • Ceramic or glass wells
  • Dummy cannulae (Plastic Products)
  • Internal cannulae (33‐G; Plastic Products)
  • Spandex jacket (Harvard Apparatus)
  • Plastic shoebox
  • Social‐interaction box (36‐in. length × 36‐in. width × 12‐in. height with open top)
  • Computer with telemetry software
  • Infusion pump (200 nl to 1 ml per minute capacity)
  • 10‐µl microsyringes
  • PE 20 tubing

Alternate Protocol 1: Lactate Challenge in Bicuculline Methiodide–Primed Rats

  • Bicuculline methiodide (BMI)

Basic Protocol 2: Developing Panic‐Prone State in Rats by Administration of L‐Allylglycine in the Dorsomedial Hypothalamus

  • Hydrogen peroxide, optional
  • Bicuculline methiodide/saline solution
  • L‐allylglycine or D‐allylglycine solution
  • Osmotic pump cannula (Plastics One)
  • Tygon tubing (0.020‐in. i.d., 0.060‐in. o.d.)
  • 25‐G needle
  • 10‐µl Hamilton syringe
  • Microsyringe pump (Harvard Apparatus)
  • Cannula holder (Plastics One)
  • Osmotic Alzet minipumps (14 day, model 2002)
  • Alzet brain infusion kit

Support Protocol 1: Behavioral Assessment of Rats in the Social Interaction Test

  Materials
  • Rat subject
  • Light source (e.g., red light)
  • Social interaction box
  • Camera
  • VCR
  • Monitor
  • Video tape
NOTE: When using the dorsomedial hypothalamus model (i.e., Sprague‐Dawley rats), it is not necessary to run the paradigm in red light. Normal room and house lighting is fine.
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Figures

Videos

Literature Cited

Literature Cited
   Adolphs, R., Tranel, D., Damasio, H., and Damasio, A.R. 1995. Fear and the human amygdala. J. Neurosci. 15:5879‐5891.
   Bernardis, L.L. and Bellinger, L.L. 1987. The dorsomedial hypothalamic nucleus revisited: 1986 Update. Brain Res. 434:321‐381.
   Charney, D.S., Heninger, G.R., and Breier, A. 1984. Noradrenergic function in panic anxiety. Effects of yohimbine in healthy subjects and patients with agoraphobia and panic disorder. Arch. Gen. Psychiatry 41:751‐763.
   Davis, M., 1992. The role of amygdala in the fear‐potentiated startle: Implications for animal models of anxiety. Trends Pharmacol. Sci. 13:35‐42.
   DiMicco, J.A., Soltis, R.P., Anderson, J.J., and Wible, J.H. Jr. 1992. Hypothalamic mechanisms and the cardiovascular response to stress. In Central Neural Mechanisms in Cardiovascular Regulation, vol. 2. (G. Kunos and J. Ciriello, eds.) pp. 52‐79. Birkhauser, Boston.
   File, S.E. 1980. The use of social interaction as a method for detecting anxiolytic activity of chlordiazepoxide‐like drugs. J. Neurosci. Methods 2:219‐238.
   Gorman, J.M., Fyer, M.R., Liebowitz, M.R., and Klein, D.F. 1987. Pharmocological provocation of panic attacks. In Psychopharmacology: The Third Generation of Progress. (H.Y. Meltzer, ed.) pp. 985‐993. Raven Press, New York..
   Keim, S.R. and Shekhar, A. 1996. Effects of GABAA receptor blockade in the dorsomedial hypothalamus of rats on ACTH and corticosterone secretion. Brain Res. 739:46‐51.
   Klein, D.F. 1993. False suffocation alarms, spontaneous panics and related conditions: An integrative hypothesis. Arch. Gen. Psychiatry 50:306‐317.
   LeDoux, J.E. 1992. Emotion and the amygdala. In The Amygdala: Neurobiological Aspects of Emotion, Memory and Mental Dysfunction (J.P. Aggleton ed.) pp. 339‐351. Wiley‐Liss, New York.
   Liebowitz, M.R., Gorman, J.M. Fyer, A., Dillon, D., Levitt, M., and Klein, D.F. 1986. Possible mechanisms for lactate's induction of panic. Am. J. Psychiatry 143:495‐502.
   Pitts, F.N. and McClure, J.N. 1967. Lactate metabolism in anxiety neurosis. N. Engl. J. Med. 227:1329‐1336.
   Reiman, E.M., Raichle, M.E., Robins, E., Mintun, M.A., Fusselman, M.J., Fox, P.T., Price, J.L., and Hackman, K.A. 1989. Neuroanatomical correlates of a lactate‐induced anxiety attack. Arch. Gen. Psychiatry 46:493‐500.
   Sajdyk, T.J., Schober, D.A. Gehlert, D.R., and Shekhar, A. 1999. Role of corticotropin‐releasing factor and urocortin within the basolateral amygdala of rats in anxiety and panic responses. Behav. Brain Res. 100:207‐215.
   Sajdyk, T.J. and Shekhar, A. 1997a. Sodium lactate induced panic response in rats following induction of long‐term synaptic plasticity in the basolateral amygdala. Soc. Neurosci. Abstr. 23:2379.
   Sajdyk, T.J. and Shekhar, A. 1997b. Excitatory amino acid receptors in the basolateral amygdala regulate anxiety responses in the social interaction test. Brain Res. 764:262‐264.
   Sajdyk, T.J. and Shekhar, A. 1997c. Excitatory amino acid receptor antagonists block the cardiovascular and anxiety responses elicited by γ‐aminobutyric acidA receptor blockade in the basolateral amygdala of rats. J. Pharmacol. Exp. Ther. 283:969‐977.
   Sajdyk, T.J. and Shekhar, A. 2000. Sodium lactate elicits anxiety in rats after repeated GABA receptor blockade in the basolateral amygdala. Eur. J. Pharmacol. 394:265‐273.
   Sanders, S.K., Morzorati, S.L., and Shekhar, A. 1995. Priming of experimental anxiety by repeated subthreshold GABA blockade in the rat amygdala. Brain Res. 699:250‐259.
   Sanders, S.K. and Shekhar, A. 1991. Blockade of GABAA receptors in the region of the anterior basolateral amygdala of rats elicits increases in heart rate and blood pressure. Brain Res. 576:101‐110.
   Shekhar, A. 1993. GABA blockade in the region of the dorsomedial hypothalamus regulates “anxiety” in rats in the elevated plus‐maze: I. Behavioral measures. Brain Res. 512:81‐88.
   Shekhar, A. 1994. Effects of chronic treatment with imipramine and clonazepam in an animal model of panic disorder. Biol. Psychiatry 36: 748‐758.
   Shekhar, A. and DiMicco, J.A. 1987. Defense reaction elicited by injection of GABA antagonists and synthesis inhibitors into the posterior hypothalamus in rats. Neuropharmacol. 26:407‐417.
   Shekhar, A. and Katner, J.S. 1995. GABAA receptors in the dorsomedial hypothalamus of rats regulate anxiety in the social interaction test. Pharmacol. Biochem. Behav. 50:253‐258.
   Shekhar, A. and Keim, S.R. 1997. The circumventricular organs form a potential neural pathway for lactate sensitivity: Implications for panic disorder. J. Neurosci. 17:9726‐9735.
   Shekhar, A. and Keim, S.R. 2000. LY354740, a potent group II metabotropic glutamate receptor agonist prevents lactate‐induced panic‐like response in panic‐prone rats. Neuropharm. 39:1139‐1146.
   Shekhar, A., Hingtgen, J.N., and DiMicco, J.A. 1987. Selective enhancement of shock avoidance responding elicited by GABA blockade in the posterior hypothalamus of rats. Brain Res. 420:118‐128.
   Shekhar, A., Keim, S.R., Simon, J.R., and McBride, W.J. 1996. Dorsomedial hypothalamic GABA dysfunction produces physiological arousal following sodium lactate infusions. Pharmacol. Biochem. Behav. 55:249‐256.
   Shekhar, A., Sajdyk, T.J., Keim, S.R., Yoder, K.K., and Sanders, S.K. 1999. The role of the basolateral amygdala in panic disorder. Ann. N.Y. Acad. Sci. 877:747‐750.
   Shekhar, A., McCann, U.D., Meany, M., Blanchard, C.D., Davis, M., Frey, K.A., Liberzon, I., Overall, K., Shear, K., Tecott, L.H., and Winsky, L. 2001. Developing animal models of anxiety disorders: A consensus paper from the National Institute of Mental Health. Psychopharmacol. 157:327‐339.
   Shekhar, A., Ball, S.G., Sajdyk, T.J., and Goddrad, A.W. 2002. Neurobiology of panic disorder. Tren. Econ. Neurosci. 4:36‐41.
   Singewald, N. and Sharp, T. 2000. Neuroanatomical targets of anxiogenic drugs in the hindbrain as reveiled by Fos immunocytochemistry. Neurosci. 98:759‐770.
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