Identification of glucagon receptors in human adipocytes from a liposarcoma.
The presence of glucagon receptors on human adipocytes has not yet been described. In this work we present an exceptional case of glucagon binding to human adipocytes taken from a malignant tumor of adipose tissue of a patient with a liposarcoma. Binding analysis revealed that the total number of glucagon receptors on liposarcoma-cells was 99,000 and the apparent receptor affinity (ED:50) was 5 x 10(-9) M. Despite the presence of these specific receptors, glucagon was unable to induce a lipolytic response, or to activate the adenylate-cyclase system in these liposarcoma-cells. Whether the induction of glucagon receptors is a specific process of the tumor biology remains to be elucidated.
Carranza
M C
MC
Department of Biochemistry, School of Medicine, Complutense University, Madrid, Spain.
Simón
M A
MA
Torres
A
A
Romero
B
B
Calle
C
C
D000273:Adipose Tissue / Q000378:metabolism* / Q000473:pathology; D000328:Adult; D005260:Female; D005934:Glucagon / Q000378:metabolism*; D006801:Humans; D008080:Liposarcoma / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011964:Receptors, Gastrointestinal Hormone / Q000378:metabolism*; D018027:Receptors, Glucagon; D012186:Retroperitoneal Neoplasms / Q000378:metabolism* / Q000473:pathology
D011964:Receptors, Gastrointestinal Hormone; D018027:Receptors, Glucagon; D005934:Glucagon