Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

Intrahypothalamic connections: An electron microscopic study in the rat

  • 41 Accesses

  • 38 Citations


Terminal degeneration within the hypothalamus was studied by electron microscopy 1 or 2 days (1) after carefully placed microlesions in the arcuate, anterior periventricular, ventromedial, premammillary and posterior hypothalamic nuclei and (2) after microlesions placed in the hypothalamus deafferented 3 weeks earlier.

In the median eminence terminal degeneration was found after each of these lesions. Projections from the ventromedial nucleus reach the arcuate, suprachiasmatic, and anterior periventricular nuclei.

Projections from the arcuate nucleus terminate in the medial preoptic, anterior periventricular, and ventromedial nuclei.

After lesioning the premammillary nuclei degeneration was found in the supraoptic, arcuate, anterior hypothalamic and ventromedial nuclei.

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


  1. Ajika, K., Hökfelt, T.: Projections to the median eminence and the arcuate nucleus with special reference to monoamine systems: effects of lesions. Cell Tiss Res 158, 15–36 (1975)

  2. Björklund, A., Moore, R.Y., Nobin, A., Stenevi, U.: The organization of tubero-hypophyseal and reticulo-infundibular catecholamine system in the rat brain. Brain Res 51, 171–191 (1973)

  3. Bodoky, M., Réthelyi, M.: Dendritic arborization and axon trajectory of neurons in the hypothalamic arcuate nucleus of the rat. Exp. Brain Res 28, 543–555 (1977)

  4. Conrad, L.C.A., 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 169, 185–220 (1976a)

  5. Conrad, L.C.A., Pfaff, D.W.: Efferents from medial basal forebrain and hypothalamus in the rat. II. An autoradiographic study of the anterior hypothalamus. J Comp Neurol 169, 221–262 (1976b)

  6. Halász, B., Köves, K., Réthelyi, M., Bodoky, M., Koritsánszky, S.: Recent data on neuronal connections between nervous structures involved in the control of the adenohypophysis. In: Anatomical Neuroendocrinology (eds. W.E. Stumpf and L.D. Grant), pp. 9–14. Basel: Karger 1975

  7. Halász, B., Pupp, L.: Hormone secretion of the anterior pituitary gland after physical interruption of all nervous pathways to the hypophysiotrophic area. Endocrinology 77, 553–562 (1965)

  8. Halász, B., Réthelyi, M., Szentágothai, J.: Examens électromicroscopiques sur l'éminence médiane isolée (désafférentée neuralement). Arch Anat (Strasbourg) 51, 289–298 (1968)

  9. 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 81, 404–412 (1974)

  10. Köves, K., Réthelyi, M.: Direct neural connection from the medial preoptic area to the hypothalamic arcuate nucleus of the rat. Exp Brain Res 25, 529–539 (1976)

  11. Makara, G.B., Harris, M.C., Spyer, K.M.: Identification and distribution of tuberoinfundibular neurones. Brain Res. 40, 283–290 (1972)

  12. Makara, G.B., Hodács, L.: Rostral projections from the hypothalamic arcuate nucleus. Brain Res 84, 23–29 (1975)

  13. Millhouse, O.E.: The organization of the ventromedial hypothalamic nucleus. Brain Res 55, 71–87 (1973a)

  14. Millhouse, O.E.: Certain ventromedial hypothalamic afferents. Brain Res 55, 89–105 (1973b)

  15. Palkovits, M.: Isolated removal of hypothalamic nuclei for neuroendocrinological and neurochemical studies. In: Anatomical Neuroendocrinology (eds. W.E. Stumpf and L.D. Grant), pp. 72–80. Basel: Karger 1975

  16. Palkovits, M., Záborszky, L.: Neural connections of the hypothalamus. In: Handbook of the Hypothalamus (eds. P.J. Morgane and I. Panksepp). New York: Dekker 1978

  17. Raisman, G.: A second look at the parvicellular neurosecretory system. In: Brain-Endocrine Interaction. Median Eminence: Structure and Function (eds. K.M. Knigge, D.E. Scott, and A. Weindl), pp. 109–118. Basel: Karger 1972

  18. Raisman, G., Matthews, M.R.: Degeneration and regeneration of synapses. In: The Structure and Function of Nervous Tissue (ed. G. Bourne), pp. 61–104. New York: Academic Press 1972

  19. Renaud, L.P.: Tuberoinfundibular neurones in the baso-medial hypothalamus of the rat: electrophysiological evidence for axon collaterals to hypothalamic areas. Brain Res 105, 59–72 (1976)

  20. Renaud, L.P.: Influence of medial preoptic-anterior hypothalamic area stimulation on the excitability of mediobasal hypothalamic neurones in the rat. J Physiol (Lond) 264, 541–564 (1977)

  21. Saper, C.B., Swanson, L.W., Cowan, W.M.: The efferent connections of the ventromedial nucleus of the hypothalamus of the rat. J Comp Neurol 169, 409–442 (1976)

  22. Scott, D.E., Knigge, K.M.: Ultrastructural changes in the median eminence of the rat following deafferentation of the basal hypothalamus. Z Zellforsch 105, 1–32 (1970)

  23. Swanson, L.W.: An autoradiographic study of the efferent connections of the preoptic region in the rat. J Comp Neurol 167, 227–256 (1976)

  24. Szentágothai, J.: The synaptic architecture of the hypothalamo-hypophyseal neuron system. Acta Neurol Belg 69, 453–468 (1969)

  25. Szentágothai, J., Flerkó, B., Mess, B., Halász, B.: Hypothalamic Control of the Anterior Pituitary. pp. 40–68. Budapest: Akadèmiai Kiadó 1962

  26. Záborszky, L., Léránth, Cs., Palkovits, M.: Gold-thioglucose induced terminal degeneration in mouse hypothalamus. Experientia 30, 811–814 (1974)

  27. Záborszky, L., Léránth, Cs., Makara, G.B., Palkovits, M.: Quantitative studies on the supraoptic nucleus in the rat. II. Afferent fiber connections. Exp Brain Res 22, 525–540 (1975)

Download references

Author information

Correspondence to Dr. L. Záborszky.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Záborszky, L., Makara, G.B. Intrahypothalamic connections: An electron microscopic study in the rat. Exp Brain Res 34, 201–215 (1979). https://doi.org/10.1007/BF00235668

Download citation

Key words

  • Intrahypothalamic connections
  • Deafferentation
  • Electron microscopy
  • Rat