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. 2005 Jun;25(3-4):663–672. doi: 10.1007/s10571-005-4006-2

Neural Connections Between Prosencephalic Structures Involved in Vasopressin Release

Rodrigo F Tavares 1, Karen B P Fernandes 1, Gisela P Pajolla 1, Iure A C Nascimento 1, Fernando M A Corrêa 1,✉
PMCID: PMC11529490  PMID: 16075384

Abstract

1. The diagonal band (DB) and the lateral septal area (LSA) are two prosencephalic structures, which were implicated in vasopressin release.

2. The present experiment was designed to investigate neural connections between the DB and the LSA and from these nuclei to the paraventricular (PVN) and supraoptic (SON) nuclei, which could be related to vasopressin release.

3. For the above purpose the bidirectional neuronal tracer biotinylated dextran amine (BDA) was injected into the DB or the LSA of male Wistar rats. Five days later the animals were sacrificed and brain slices were processed and analyzed to determine neuronal projections efferent from as well as afferent to these structures.

4. Neuronal staining was more prominent in regions ipsilateral to the BDA injection site.

5. After BDA injections into the DB, efferent projections from the DB were observed at the LSA, the PVN, the prefrontal cortex, the mediodorsal thalamic nucleus, and throughout the anterior hypothalamus, but not at the SON. At the PVN, labeled varicose fibers were observed at the magnocellular portion. The DB was found to receive a massive input from the LSA. More discrete projections to the DB were originated at the prefrontal cortex and from hypothalamic neurons outside the PVN and the SON.

6. After BDA injections into the ventral portion of the LSA, efferent projections from the LSA were intense at the DB and throughout the hypothalamus. Labeled fibers were observed at the structures surrounding the SON or the PVN but not within those nuclei.

7. The results indicate a massive neural output from the LSA to the DB and the existence of a direct neural connection from the DB to the PVN. No direct connections were observed between the LSA and the magnocellular nuclei (PVN and SON) or between the DB and the SON.

Key Words: diagonal band, lateral septal area, paraventricular nucleus, supraoptic nucleus, biotinylated dextran amine, neural connections, blood pressure, cardiovascular control, vasopressin release

References

  1. Corrêa, F. M. A., and Peres-Polon, V. L. (1978). Effect of electrical stimulation of lateral septal area on blood pressure in anesthetized and unanesthetized rats. Acta Physiol. Latinoam. 28(Suppl. 1):69–71. [PubMed] [Google Scholar]
  2. Jhamandas, J. H., and Renaud, L. P. (1986). Diagonal band neurons may mediate arterial baroreceptor input to hypothalamic vasopressin-secreting neurons. Neuroscience65:214–218. [DOI] [PubMed] [Google Scholar]
  3. Kirouac, G. J., and Ciriello, J. (1997). Cardiovascular responses to glutamate stimulation of diagonal band of Broca. Am. J. Physiol. 273:H540–H545. [DOI] [PubMed] [Google Scholar]
  4. Nieuwenhuys, R., Geeraedts, L. M., and Veening, J. G. (1982). The medial forebrain bundle of the rat. I. General introduction. J. Comp. Neurol. 206(1):49–81. [DOI] [PubMed] [Google Scholar]
  5. Paxinos, G., and Watson, C. (1986). The Rat Brain in Stereotaxic Coordinates, 2nd edn., Academic. [DOI] [PubMed]
  6. Peres-Polon, V. L., and Corrêa, F. M. A. (1994). Pressor effects of acetylcholine injected into the lateral septal area of conscious rats. Neuropharmacology33:1537–1544. [DOI] [PubMed] [Google Scholar]
  7. Pirola, C. J., Balda, M. S., Alvarez, A. L., Finkelman, S., and Nahmod, V. E. (1986). Interaction between acetylcholine and bradykinin in the lateral septal area of the rat brain: Involvement of muscarinic receptors in cardiovascular responses. Neuropharmacology12:1387–1393. [DOI] [PubMed] [Google Scholar]
  8. Rohmeiss, P., Becker, H., Dietrich, R., Luft, F., and Unger, T. (1986). Vasopressin: Mechanism of central cardiovascular action in conscious rats. J. Cardiovasc. Pharmacol. 8:689–696. [PubMed] [Google Scholar]
  9. Semba, K. (2000). Multiple output pathways of the basal forebrain: Organization, chemical heterogeneity, and roles in vigilance. Behav. Brain Res. 115:117–141. [DOI] [PubMed] [Google Scholar]
  10. Senatorov, V. V., and Renaud, L. P. (1999). Projections of medullary and pontine noradrenergic neurons to the horizontal limb of the nucleus of diagonal band in the rat. Neuroscience88:939–947. [DOI] [PubMed] [Google Scholar]
  11. Share, L. (1996). Control of vasopressin release: An old but continuing story. News Physiol. Sci. 11:07–13. [Google Scholar]
  12. Tavares, R. F., and Corrêa, F. M. A. (2003). Pressor effects of l-glutamate injected into the diagonal band of Broca of unanesthetized rats. Brain Res. 959:312–319. [DOI] [PubMed] [Google Scholar]
  13. Vallejo, M., Carter, D. A., and Lightman, S. L. (1984). Haemodynamic effects of arginine-vasopressin microinjections into the nucleus tractus solitarius: A comparative study of vasopressin, a selective vasopressin receptor agonist and antagonist, and oxytocin. Neurosci. Lett. 52:247–252. [DOI] [PubMed] [Google Scholar]

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