Induction of c-fos immunoreactivity in tyrosine hydroxylase and phenylethanolamine-N-methyltransferase immunoreactive neurons of the medulla oblongata of the rat after phosphate-buffered saline load in the urethane-anaesthetized rat.
We have studied the induction of c-fos immunoreactivity (c-fos IR) in catecholaminergic and vasopressinergic immunoreactive neurons after repeated phosphate-buffered saline (PBS) loading or after repeated elicitation of the baroreceptor reflex via repeated infusion of the vasoconstrictor agent L-phenylephrine. About 75% and 30%, respectively, of the tyrosine-hydroxylase immunoreactive (IR) cell bodies of the ventral noradrenaline (NA) A1/adrenaline (A) C1 and dorsal NA A2/A C2 areas and 60% and 30%, respectively, of the phenylethanolamine N-methyltransferase IR nerve cells of the adrenaline C1 and C2 areas and 25% of the vasopressin (VP) IR neurons of the supraoptic (SO) nucleus developed nuclear c-fos IR after repeated PBS loading. This phenomenon remained unaltered by the repeated elicitation of the baroreceptor reflex. These results suggest that the activation of volume receptors promotes homeostatic responses via activation of early genes in subsets of central medullary noradrenaline and adrenaline neurons and SO VP neurons of the urethane-anaesthetized rat.
Narváez
J A
JA
Department of Physiology, University of Málaga, Spain.
Coveñas
R
R
de León
M
M
Aguirre
J A
JA
Cintra
A
A
Goldstein
M
M
Fuxe
K
K
D000595:Amino Acid Sequence; D000758:Anesthesia; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D008526:Medulla Oblongata / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D008969:Molecular Sequence Data; D009474:Neurons / Q000276:immunology / Q000378:metabolism*; D010656:Phenylephrine / Q000494:pharmacology; D010625:Phenylethanolamine N-Methyltransferase / Q000276:immunology / Q000378:metabolism*; D010710:Phosphates / Q000494:pharmacology; D016760:Proto-Oncogene Proteins c-fos / Q000276:immunology / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013495:Supraoptic Nucleus / Q000276:immunology / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000276:immunology / Q000378:metabolism*; D014520:Urethane
D010710:Phosphates; D016760:Proto-Oncogene Proteins c-fos; D010656:Phenylephrine; D014520:Urethane; D014446:Tyrosine 3-Monooxygenase; D010625:Phenylethanolamine N-Methyltransferase