Skip to main content
SpringerLink
Log in

A study of the amygdaloid defence reaction showing the value of Althesin anaesthesia in studies of the functions of the fore-brain in cats

  • Excitable Tissues and central Nervous Physiology
  • Published:
Pflügers Archiv Aims and scope Submit manuscript

Abstract

  1. 1.

    In cats under Althesin (alphaxalone-alphadalone) anaesthesia, sites in the amygdala and brain-stem defence areas have been electrically stimulated by means of monopolar, semi-microelectrodes.

  2. 2.

    Such stimulation evoked a consistent pattern of visceral changes characteristic of the alerting stage of the defence reaction as it has been described by previous workers. This “visceral alerting reaction” included increases in arterial blood pressure, heart-rate and cardiac output with vasoconstriction in kidney, intestines and skin but vasodilatation in the hind limbs.

  3. 3.

    These results differ strikingly from those reported previously in that, under conventional anaesthetics, such as chloralose or barbiturate, the full visceral alerting reaction cannot be evoked by amygdala stimulation, or any other manoeuvre which involves transmission through the brain stem defence areas.

  4. 4.

    The area of the amygdala from which such responses can be elicited under Althesin closely resembles that which has been reported to evoke defence reactions in conscious animals.

  5. 5.

    It is concluded that Althesin, used in the manner described, does not distort synaptic transmission in the forebrain in the way that conventional anaesthetics do. It is suggested that this steroid anaesthetic may be invaluable in any studies of fore-brain physiology in the cat

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Abrahams VC, Hilton SM, Zbrozyma AW (1960) Active muscle vasodilatation produced by stimulation in the brain stem. Its significance in the defence reaction. J Physiol (Lond) 154:491–513

    Google Scholar 

  • Abrahams VC, Hilton SM, Malcolm JL (1962) Sensory connections of the hypothalamus and mid-brain, and their role in the reflex activation of the defence reaction. J Physiol (Lond) 164:1–16

    Google Scholar 

  • Abrahams VC, Hilton SM, Zbrozyna AW (1964) The role of active muscle vasodilatation in the alerting stage of the defence reaction. J Physiol (Lond) 171:189–202

    Google Scholar 

  • Caraffa-Braga E, Granata L, Pinotti O (1973) Changes in blood flow distribution during emotional stress in dogs. Pflügers Arch 339:203–216

    Google Scholar 

  • Child KJ, Currie JP, Davis B, Dodds MG, Pearce DR, Twissell DJ (1971) The pharmacological properties in animals of CT1341—a new steroid anaesthetic agent. Br J Anaesth 43:2–13

    Google Scholar 

  • Child KJ, Davis B, Dodds MG, Twissell DJ (1972) Anaesthetic, cardiovascular and respiratory effects of a new steroidal agent CT1341: a comparison with other intravenous anaesthetic drugs in the unrestrained cat. Br J Pharmacol 46:189–200

    Google Scholar 

  • Coote JH, Hilton SM, Zbrozyna AW (1973) The ponto-medullary area integrating the defence reaction in the cat and its influence on muscle blood flow. J Physiol (Lond) 229:257–274

    Google Scholar 

  • Djojosugito AM, Folkow B, Kylstra PH, Lisander B, Tuttle RS (1970) Differentiated interaction between the hypothalamic defence reaction and baroreceptor reflexes. I. Effects on heart-rate and regional flow resistance. Acta Physiol Scand 78:376–385

    Google Scholar 

  • Eliasson S, Folkow B, Lindgren P, Uvnäs B (1951) Activation of sympathetic vasodilator nerves to the skeletal muscles in the cat by hypothalamic stimulation. Acta Physiol Scand 23:333–351

    Google Scholar 

  • Green JD (1958) A simple microelectrode for recording from the central nervous system. Nature 182:962

    Google Scholar 

  • Hilton SM (1965) Hypothalamic control of the cardiovascular responses in fear and rage. In: The scientific basis of medicine annual reviews. Athlone Press. London, pp 217–238

    Google Scholar 

  • Hilton SM (1975) Ways of viewing the central nervous control of the circulation—old and new. Brain Res 87:213–219

    Google Scholar 

  • Hilton SM, Zbrozyna AW (1963) Amygdaloid region for defence reactions and its efferent pathway to the brain stem. J Physiol (Lond) 165:160–173

    Google Scholar 

  • Jänig W, Räth B (1980) Effects of anaesthetics on reflexes elicited in the sudomotor system by stimulation of Pacinian corpuscles and of cutaneous nociceptors. J Auton Nerv Syst 2:1–14

    Google Scholar 

  • Kylstra PH, Lisander B (1970) Differentiated interaction between the hypothalamic defence area and baroreceptor reflexes. II. Effects on aortic blood flow as related to work load on the left ventricle. Acta Physiol Scand 78:386–392

    Google Scholar 

  • MacLean PD, Delgado JMR (1953) Electrical and chemical stimulation of frontotemporal portion of limbic system in the waking animal. Electroencephalogr Clin Neurophysiol 5:91–100

    Google Scholar 

  • Marshall JM (1977) The cardiovascular response to stimulation of carotid chemoreceptors. J Physiol (Lond) 266:48–49P

    Google Scholar 

  • Martin J, Sutherland CJ, Zbrozyna AW (1976) Habituation and conditioning of the defence reactions and their cardiovascular components in cats and dogs. Pflügers Arch 365:37–47

    Google Scholar 

  • Miller D (1976) A multi-purpose rate-meter. J Physiol (Lond) 256:68–69 P

    Google Scholar 

  • Schramm LP, Bignall KE (1971) Central neural pathways mediating active sympathetic muscle vasodilation in cats. Am J Physiol 221:754–767

    Google Scholar 

  • Selye H (1941) Anaesthetic effects of steroid hormones. Proc Soc Exp Biol Med 46:116–121

    Google Scholar 

  • Snider RS, Niemer WT (1961) A stereotaxic atlas of the cat brain. University of Chicago Press, Chicago

    Google Scholar 

  • Stock G, Schlör KH, Heidt H, Buss J (1978) Psychomotor behaviour and cardiovascular patterns during stimulation of the amygdala. Pflügers Arch 376:177–184

    Google Scholar 

  • Timms RJ (1976) The use of the anaesthetic steroids alphaxalonealphadolone in studies of the forebrain in the cat. J Physiol (Lond) 256:71–72P

    Google Scholar 

  • Timms RJ (1977a) Influences of the frontal cerebral cortex and corticospinal tract on the cardiovascular system. Ph. D. Thesis; University of Birmingham. England

    Google Scholar 

  • Timms RJ (1977b) Cortical inhibition and facilitation of the defence reaction. J Physiol (Lond) 266:98–99P

    Google Scholar 

  • Valverde F (1965) Studies on the piriform lobe. Harvard University Press, Cambridge, Mass

    Google Scholar 

  • Zbrozyna AW (1972) The organization of the defence reaction elicited from amygdala and its connections. In: Eleftheriou BE (ed) The neurobiology of the amygdala. Plenum Press, New York, pp 597–606

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Physiology, The Medical School, Vincent Drive, B15 2TJ, Birmingham, UK

    Robert J. Timms

Authors
  1. Robert J. Timms
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

Timms, R.J. A study of the amygdaloid defence reaction showing the value of Althesin anaesthesia in studies of the functions of the fore-brain in cats. Pflugers Arch. 391, 49–56 (1981). https://doi.org/10.1007/BF00580694

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00580694

Key words

Search

Navigation