Arginine-vasopressin neurons in the rat hypothalamus produce neurokinin B and co-express the tachykinin NK-3 receptor and angiotensin II type 1 receptor.
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.
Hatae
T
T
Department of Anatomy, Saga Medical School, Japan. thatae@nisikyu-u.ac.jp
Kawano
H
H
Karpitskiy
V
V
Krause
J E
JE
Masuko
S
S
D000818:Animals; D001127:Arginine Vasopressin / Q000096:biosynthesis*; D004797:Enzyme-Linked Immunosorbent Assay; D005455:Fluorescent Antibody Technique; D007150:Immunohistochemistry; D008297:Male; D015287:Neurokinin B / Q000096:biosynthesis / Q000276:immunology*; D009474:Neurons / Q000276:immunology / Q000378:metabolism; D010286:Paraventricular Hypothalamic Nucleus / Q000276:immunology / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011945:Receptors, Angiotensin / Q000276:immunology / Q000378:metabolism*; D018042:Receptors, Neurokinin-3 / Q000276:immunology / Q000378:metabolism*; D013495:Supraoptic Nucleus / Q000276:immunology / Q000378:metabolism*; D015320:Tachykinins / Q000378:metabolism
D011945:Receptors, Angiotensin; D018042:Receptors, Neurokinin-3; D015320:Tachykinins; D001127:Arginine Vasopressin; D015287:Neurokinin B