Presentation is loading. Please wait.

Presentation is loading. Please wait.

Regulation of Adipocyte Lipolysis Catecholamines –Epinephrine & Norepinephrine Beta Adrenergic Receptors –Stimulate Alpha Adrenergic Receptors –Inhibit.

Similar presentations


Presentation on theme: "Regulation of Adipocyte Lipolysis Catecholamines –Epinephrine & Norepinephrine Beta Adrenergic Receptors –Stimulate Alpha Adrenergic Receptors –Inhibit."— Presentation transcript:

1 Regulation of Adipocyte Lipolysis Catecholamines –Epinephrine & Norepinephrine Beta Adrenergic Receptors –Stimulate Alpha Adrenergic Receptors –Inhibit Insulin –Inhibitory

2 Catecholamines Stimulatory –B-Adrenergic Receptors –Activates Stimulatory G- Protein –Activates Adenylate Cyclase –Generates cAMP –Activates cAMP-dependent protein kinase –Phosphorylates HSL & Perilipins –Break down triglycerides Inhibitory –A-Adrenergic Receptors –Activates Inhibitory G-protein –Inhibits Adenylate Cyclase

3 Catecholamines stimulate HSL to break down triglycerides to fatty acids and glycerol Fatty acids and glycerol are released into the blood and circulated to other body tissues

4 ATGL Adipose Triglyceride Lipase –Enzyme that may be responsible for catalyzing the initial steps of triglyceride hydrolysis. –Zimmermann et al. (2004) HSL knock-out mice showed an accumulation of diglycerides, suggesting that additional lipases may be present that can hydrolyze the first ester bond of triglycerides –Still controversial

5 Insulin Lipoprotein Lipase (LPL) Phosphatidylinositol 3-Kinase (PI3K) Phosphodiesterase-3 Degrades cAMP Hydrolyzes Plasma Triglycerides Into FFA Phosphorylates

6 Insulin & LPL

7 Insulin LPL –Hydrolyzes triglycerides in the blood to increase FFA levels PI3K –Inhibits lipolysis in adipose cells –Mediates insulin- stimulated glucose uptake PI3K Phosphodiestesterase-3 Phosphorylates Degrades


Download ppt "Regulation of Adipocyte Lipolysis Catecholamines –Epinephrine & Norepinephrine Beta Adrenergic Receptors –Stimulate Alpha Adrenergic Receptors –Inhibit."

Similar presentations


Ads by Google