Skip to main content
NCBI home page
The Journal of Physiology logoLink to The Journal of Physiology
. 1980;300:515–524. doi: 10.1113/jphysiol.1980.sp013176

Amygdala neurones: converging synaptic inputs produced by median eminence and medial preoptic area stimulations in rats

Mitsuko Hamamura 1, Kinji Yagi 1
PMCID: PMC1279369  PMID: 7381795

Abstract

1. Amygdaloid afferent inputs from the median eminence and the medial preoptic area were studied electrophysiologically in urethane-anaesthetized female rats.

2. Stimulation of the surface of the median eminence produced orthodromic responses in about 80% of the forty-seven amygdala units tested and about 65% of the responsive cells showed an excitation.

3. Stimulation of the ipsilateral medial preoptic area orthodromically excited seventeen and inhibited twenty of the forty-nine units tested.

4. Stimulation of the contralateral medial preoptic area evoked orthodromic excitation in nine and inhibition in three of the twenty-two units tested. These stimuli were ineffective for producing antidromically conducted impulses in the tested units.

5. Sixteen of the thirty amygdala units tested for responses to both median eminence and ipsilateral medial preoptic area stimulation responded orthodromically with either excitation or inhibition. The latency of the response to median eminence stimulation was approximately equal to that of the response to ipsilateral preoptic area stimulation in four of these sixteen units.

6. A characteristic bursting discharge was observed in eleven amygdala units during and after ipsilateral preoptic area stimulation. A transitory inhibition was evoked simultaneously with the bursting discharge in some units. Seven of the eleven units were also tested for median eminence stimulation, and a transitory excitation was observed in each of these units.

7. These results suggest the existence of converging synaptic inputs both from tuberoinfundibular neurones and the ipsilateral medial preoptic area to certain amygdala neurones. They also demonstrate the existence of a specific neural pathway mediating a characteristic self-sustained bursting discharge in some amygdala neurones after such stimulation.

Full text

PDF
515

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Beltramino C., Taleisnik S. Facilitatory and inhibitory effects of electrochemical stimulation of the amygdala on the release of luteinizing hormone. Brain Res. 1978 Apr 7;144(1):95–107. doi: 10.1016/0006-8993(78)90437-7. [DOI] [PubMed] [Google Scholar]
  2. Brown-Grant K., Exley D., Naftolin F. Peripheral plasma oestradiol and luteinizing hormone concentrations during the oestrous cycle of the rat. J Endocrinol. 1970 Oct;48(2):295–296. doi: 10.1677/joe.0.0480295. [DOI] [PubMed] [Google Scholar]
  3. Carrer H. F., Whitmoyer D. I., Sawyer C. H. Effects of hippocampal and amygdaloid stimulation on the firing of preoptic neurons in the proestrous female rat. Brain Res. 1978 Feb 24;142(2):363–367. doi: 10.1016/0006-8993(78)90644-3. [DOI] [PubMed] [Google Scholar]
  4. Conrad L. C., Pfaff D. W. Efferents from medial basal forebrain and hypothalamus in the rat. I. An autoradiographic study of the medial preoptic area. J Comp Neurol. 1976 Sep 15;169(2):185–219. doi: 10.1002/cne.901690205. [DOI] [PubMed] [Google Scholar]
  5. Dyer R. G., MacLeod N. K., Ellendorff F. Electrophysiological evidence for sexual dimorphism and synaptic convergence in the preoptic and anterior hypothalamic areas of the rat. Proc R Soc Lond B Biol Sci. 1976 Jun 30;193(1113):421–440. doi: 10.1098/rspb.1976.0055. [DOI] [PubMed] [Google Scholar]
  6. Ellendorff F., MacLeod N. K., Dyer R. G. Bipolar neurones in the rostral hypothalamus. Brain Res. 1976 Jan 23;101(3):549–553. doi: 10.1016/0006-8993(76)90477-7. [DOI] [PubMed] [Google Scholar]
  7. Harris M. C., Sanghera M. Projection of medial basal hypothalamic neurones to the preoptic anterior hypothalamic areas and the paraventricular nucleus in the rat. Brain Res. 1974 Dec 13;81(3):401–411. doi: 10.1016/0006-8993(74)90839-7. [DOI] [PubMed] [Google Scholar]
  8. Hori T., Ide M., Miyake T. Ovarian estrogen secretion during the estrous cycle and under the influence of exogenous gonadotropins in rats. Endocrinol Jpn. 1968 Jun;15(2):215–222. doi: 10.1507/endocrj1954.15.215. [DOI] [PubMed] [Google Scholar]
  9. Hökfelt T., Efendic S., Johansson O., Luft R., Arimura A. Immunohistochemical localization of somatostatin (growth hormone release-inhibiting factor) in the guinea pig brain. Brain Res. 1974 Nov 8;80(1):165–169. doi: 10.1016/0006-8993(74)90737-9. [DOI] [PubMed] [Google Scholar]
  10. KREINDLER A., STERIADE M. FUNCTIONAL DIFFERENTIATION WITHIN THE AMYGDALOID COMPLEX INFERRED FROM PECULIARITIES OF EPILEPTIC AFTER DISCHARGES. Electroencephalogr Clin Neurophysiol. 1963 Oct;15:811–826. doi: 10.1016/0013-4694(63)90172-x. [DOI] [PubMed] [Google Scholar]
  11. Krieger M. S., Conrad L. C., Pfaff D. W. An autoradiographic study of the efferent connections of the ventromedial nucleus of the hypothalamus. J Comp Neurol. 1979 Feb 15;183(4):785–815. doi: 10.1002/cne.901830408. [DOI] [PubMed] [Google Scholar]
  12. Le Gal La Salle G. Unitary responses in the amygdaloid complex following stimulation of various diencephalic structures. Brain Res. 1976 Dec 24;118(3):475–478. doi: 10.1016/0006-8993(76)90315-2. [DOI] [PubMed] [Google Scholar]
  13. Makara G. B., Harris M. C., Spyer K. M. Identification and distribution of tuberoinfundibular neurones. Brain Res. 1972 May 26;40(2):283–290. doi: 10.1016/0006-8993(72)90134-5. [DOI] [PubMed] [Google Scholar]
  14. Miescher K., Scholz C., Tschopp E. The activation of female sex hormones: alpha-Oestradiol and its di-esters. Biochem J. 1938 Apr;32(4):725–732. doi: 10.1042/bj0320725. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Pasley J. N., Powell E. W., Cernosek R. M., Cernosek S. F. Effects of amygdaloid lesions on reproductive function of grouped caged mice. Neuroendocrinology. 1978;25(2):77–83. doi: 10.1159/000122731. [DOI] [PubMed] [Google Scholar]
  16. Perkins M. N., Demaine C., Whitehead S. A. Electrophysiological and pharmacological studies of amygdalo-hypothalamic connections in the rat. Neuroendocrinology. 1977;23(4):200–211. doi: 10.1159/000122668. [DOI] [PubMed] [Google Scholar]
  17. Renaud L. P., Hopkins D. A. Amygdala afferents from the mediobasal hypothalamus: an electrophysiological and neuroanatomical study in the rat. Brain Res. 1977 Feb;121(2):201–213. doi: 10.1016/0006-8993(77)90147-0. [DOI] [PubMed] [Google Scholar]
  18. Renaud L. P. Influence of amygdala stimulation on the activity of identified tuberoinfundibular neurones in the rat hypothalamus. J Physiol. 1976 Aug;260(1):237–252. doi: 10.1113/jphysiol.1976.sp011513. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Renaud L. P. Influence of medial preoptic-anterior hypothalamic area stimulation of the excitability of mediobasal hypothalamic neurones in the rat. J Physiol. 1977 Jan;264(2):541–564. doi: 10.1113/jphysiol.1977.sp011682. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Renaud L. P., Martin J. B. Electrophysiological studies of connections of hypothalamic ventromedial nucleus neurons in the rat: evidence for a role in neuroendocrine regulation. Brain Res. 1975 Jul 25;93(1):145–151. doi: 10.1016/0006-8993(75)90293-0. [DOI] [PubMed] [Google Scholar]
  21. Sawaki Y., Yagi K. Electrophysiological identification of cell bodies of the tubero-infundibular neurones in the rat. J Physiol. 1973 Apr;230(1):75–85. doi: 10.1113/jphysiol.1973.sp010175. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Sawaki Y., Yagi K. Inhibition and facilitation of antidromically identified tubero-infundibular neurones following stimulation of the median eminence in the rat. J Physiol. 1976 Sep;260(2):447–460. doi: 10.1113/jphysiol.1976.sp011524. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Swanson L. W. An autoradiographic study of the efferent connections of the preoptic region in the rat. J Comp Neurol. 1976 May 15;167(2):227–256. doi: 10.1002/cne.901670207. [DOI] [PubMed] [Google Scholar]
  24. Turner B. H., Knapp M. E. Projections of the nucleus and tracts of the stria terminalis following lesions at the level of the anterior commissure. Exp Neurol. 1976 May;51(2):468–479. doi: 10.1016/0014-4886(76)90270-3. [DOI] [PubMed] [Google Scholar]
  25. Yagi K., Sawaki Y. Medial preoptic nucleus neurons: inhibition and facilitation of spontaneous activity following stimulation of the median eminence in female rats. Brain Res. 1977 Jan 21;120(2):342–346. doi: 10.1016/0006-8993(77)90912-x. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Physiology are provided here courtesy of The Physiological Society

RESOURCES