The presence and role of hormone-sensitive lipase in heart muscle.
Biochem J
; 258(1): 67-72, 1989 Feb 15.
Article
em En
| MEDLINE
| ID: mdl-2930517
ABSTRACT
Hormone-sensitive lipase (HSL) catalyses the initial, rate-limiting, reaction in adipose-tissue lipolysis. Hormone-stimulated lipolytic activity has also been observed in the heart, where endogenous triacylglycerol is the major energy store. However, the identity of the intracellular lipase responsible has yet to be established. We have partially purified a neutral lipase from bovine heart muscle and compared its properties with those of HSL from bovine adipose tissue. The heart lipase has the same subunit Mr as HSL, is immunoprecipitated by antiserum raised against purified HSL and is phosphorylated by cyclic AMP-dependent protein kinase, apparently at the same site as HSL (as judged by h.p.l.c. of tryptic phosphopeptides). Phosphorylation of the heart lipase was found to result in increased enzyme activity, demonstrating the lipase's potential to respond to hormonal stimuli. The heart lipase was shown to be present in myocytes by its immunoprecipitation from homogenates of rat myocytes by anti-HSL antiserum. These findings are consistent with the conclusion that HSL is responsible for intracellular lipolysis in heart.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Hidrolases de Éster Carboxílico
/
Esterol Esterase
/
Miocárdio
Tipo de estudo:
Diagnostic_studies
Limite:
Animals
Idioma:
En
Revista:
Biochem J
Ano de publicação:
1989
Tipo de documento:
Article
País de afiliação:
Reino Unido