Lipolytic and antilipolytic effects of human growth hormone, its 20-kilodalton variant, a reduced and carboxymethylated derivative, and human placental lactogen on chicken adipose tissue in vitro.
The lipolytic and antilipolytic effects of human growth hormone (22K-hGH), its 20-kilodalton variant (20K-hGH), a reduced and S-carboxymethylated derivative (RCM-hGH), and human placental lactogen were examined using chicken adipose tissue explants in vitro. Lipolysis, as determined by glycerol release, was stimulated by 22K-hGH (biosynthetic and pituitary derived), 20K-hGH (pituitary derived), and RCM-hGH (modified biosynthetic). These growth hormone preparations also exhibited similar antilipolytic activity (i.e., transient inhibition of glucagon-induced lipolysis). However, unlike human growth hormone, human placental lactogen neither stimulated lipolysis nor inhibited glucagon-stimulated lipolysis. Some augmentation of glucagon-stimulated lipolysis was observed in the presence of human placental lactogen. These results indicate that the disulfide bridges (Cys53----Cys165; Cys182----Cys189) and amino acid residues 32-46 of hGH are not required for lipolytic or antilipolytic activities of human growth hormone on chicken adipose tissue.
Campbell
R M
RM
Department of Animal Sciences, Rutgers State University, New Brunswick, New Jersey 08903.
Kostyo
J L
JL
Scanes
C G
CG
D000273:Adipose Tissue / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D002645:Chickens; D046508:Culture Techniques; D013006:Growth Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology*; D008066:Lipolysis / Q000187:drug effects*; D008297:Male; D010928:Placental Lactogen / Q000494:pharmacology*
D013006:Growth Hormone; D010928:Placental Lactogen