Arginine-vasopressin neurons in the rat hypothalamus produce neurokinin B and co-express the tachykinin NK-3 receptor and angiotensin II type 1 receptor

Arch Histol Cytol. 2001 Feb;64(1):37-44. doi: 10.1679/aohc.64.37.

Abstract

Secretion of arginine-vasopressin (AVP) from the hypothalamic paraventricular (PVN) and supraoptic (SON) nuclei is induced by neurokinin B (NKB) and angiotensin. To characterize the mechanisms by which this occurs, we used immunohistochemical techniques to assess the ability of AVP-producing neurons to express NKB, NKB receptor (NK-3 receptor) and angiotensin II type 1 receptor (AT-1 receptor). Double fluorescence immunohistochemistry indicated that AVP-immunoreactive cell bodies in the PVN and SON, as well as their axon varicosities in the posterior pituitary, co-express NKB. Almost all AVP-neuron perikarya also expressed both the NK-3 receptor and AT-1 receptor. Thus, AVP-producing neurons in the PVN and SON, which are regulated by NKB, are themselves a source of NKB. Furthermore, the regulation of AVP release by these neurons by NKB and angiotensin II is mediated by the NK-3 receptor and the AT-1 receptor, respectively.

MeSH terms

  • Animals
  • Arginine Vasopressin / biosynthesis*
  • Enzyme-Linked Immunosorbent Assay
  • Fluorescent Antibody Technique
  • Immunohistochemistry
  • Male
  • Neurokinin B / biosynthesis
  • Neurokinin B / immunology*
  • Neurons / immunology
  • Neurons / metabolism
  • Paraventricular Hypothalamic Nucleus / immunology
  • Paraventricular Hypothalamic Nucleus / metabolism*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Angiotensin / immunology
  • Receptors, Angiotensin / metabolism*
  • Receptors, Neurokinin-3 / immunology
  • Receptors, Neurokinin-3 / metabolism*
  • Supraoptic Nucleus / immunology
  • Supraoptic Nucleus / metabolism*
  • Tachykinins / metabolism

Substances

  • Receptors, Angiotensin
  • Receptors, Neurokinin-3
  • Tachykinins
  • Arginine Vasopressin
  • Neurokinin B