Molecular identification of two types of interleukin-1 receptors in the murine pituitary gland.
The present study was carried out to characterize interleukin-1 (IL-1) receptors on murine pituitary cells. Receptor autoradiography confirmed the existence of binding sites for IL-1 alpha in the murine adenohypophysis, but not in the neural or intermediate lobes. Specific binding of IL-1 to isolated pituitary membranes revealed a Kd of 0.9 nM with a Bmax of 37 fmol/mg protein. To examine the possibility that the adenohypophysis synthesizes a receptor for IL-1, immunocytochemistry experiments with a specific monoclonal antibody against the type I receptor revealed the existence of this protein in only the adenohypophysis. Identity of the type I IL-1 receptor was similar to that found on T cells as determined by: 1) amplification of the predicted 619 bp fragment spanning the cytoplasmic, transmembrane and extracellular domains from RNA of pituitary and T cell origin, as well as clonal AtT-20 pituitary cells, and 2) restriction fragment analysis and sequencing of the amplified cDNAs. The pituitary gland and AtT-20 cells also expressed transcripts for the newly identified type II receptor for IL-1 as assessed by amplification of a specific 325 bp fragment, restriction fragment analysis and nucleotide sequencing, and these transcripts were similar to those found on B lymphocytes. These data identify two different forms of the IL-1 receptor in both normal and transformed pituitary cells and establish that these receptors are similar at the molecular level to those first identified on T and B lymphocytes.
Parnet
P
P
INRA-INSERM, Unité de Recherches de Neurobiologie des Comportements, U 176, Bordeaux, France.
Brunke
D L
DL
Goujon
E
E
Mainard
J D
JD
Biragyn
A
A
Arkins
S
S
Dantzer
R
R
Kelley
K W
KW
D000818:Animals; D001345:Autoradiography; D002460:Cell Line; D003001:Cloning, Molecular; D007150:Immunohistochemistry; D007202:Indicators and Reagents; D008297:Male; D051379:Mice; D008811:Mice, Inbred DBA; D010902:Pituitary Gland / Q000737:chemistry / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D012313:RNA / Q000032:analysis; D017472:Receptors, Interleukin-1 / Q000032:analysis / Q000378:metabolism*; D015183:Restriction Mapping; D014158:Transcription, Genetic
D007202:Indicators and Reagents; D017472:Receptors, Interleukin-1; D012313:RNA