Biochemical Mechanism of Magnesium

Mark H. Whitney, Jeffrey S. Knott, and Jayne L. Kalbfleisch

Central Nervous SystemSTRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic HormoneAdapted from Classen and Porta, 1996.

Hypothalamus

CRF

Pituitary

Central Nervous SystemSTRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic HormoneAdapted from Classen and Porta, 1996.

Hypothalamus

CRF

Pituitary

ACTH

Adrenal Cortex

Central Nervous SystemSTRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic HormoneAdapted from Classen and Porta, 1996.

ACTH

Adrenal Cortex

ACTH

cAMP Concentrations

Adrenal Cortex

ACTH

cAMP Concentrations

20, 22 Lyase Activation

Adrenal Cortex

ACTH

cAMP Concentrations

20, 22 Lyase Activation

Cortisol Synthesis

Adrenal Cortex

ACTH

cAMP Concentrations

20, 22 Lyase Activation

Cortisol Synthesis Glycogen Release

Adrenal Cortex

Liver

Hypothalamus

CRF

Pituitary

ACTH

Adrenal Cortex

Central Nervous System

Cortisol Liver

Glycogen

STRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic HormoneAdapted from Classen and Porta, 1996.

Hypothalamus

CRF

Pituitary

ACTH

Adrenal Cortex

Central Nervous System

Cortisol Liver

Glycogen

Muscle

Glycogen

STRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic HormoneAdapted from Classen and Porta, 1996.

Hypothalamus

CRF

Pituitary

ACTH

Adrenal Cortex

Adrenal Medulla

Central Nervous System

Cortisol Liver

Glycogen

Muscle

Glycogen

STRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic HormoneAdapted from Classen and Porta, 1996.

Hypothalamus

CRF

Pituitary

ACTH

Adrenal Cortex

Adrenal Medulla

Central Nervous System

Cortisol Liver

Glycogen

Muscle

Glycogen

Epinephrine

Muscle

Glycogen

STRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic HormoneAdapted from Classen and Porta, 1996.

Epinephrine

ATP cAMP

Adapted from Coffee, 1998.

Adenylate cyclase

Epinephrine

ATP cAMP

Protein Kinase A

Phosphorylase Kinase

Phosphorylase Kinase

P

Adapted from Coffee, 1998.

Adenylate cyclase

Epinephrine

ATP cAMP

Protein Kinase A

Phosphorylase Kinase

Phosphorylase Kinase

P

Glycogen Phosphorylase

PGlycogen

Phosphorylase

Adapted from Coffee, 1998.

Adenylate cyclase

Epinephrine

ATP cAMP

Protein Kinase A

Phosphorylase Kinase

Phosphorylase Kinase

P

Glycogen Phosphorylase

PGlycogen

Phosphorylase P

Glycogen

Glucose-1-phosphate

Adapted from Coffee, 1998.

Adenylate cyclase

Epinephrine

ATP cAMP

Protein Kinase A

Phosphorylase Kinase

Phosphorylase Kinase

P

Glycogen Phosphorylase

PGlycogen

Phosphorylase P

Glycogen

Glucose-1-phosphate

GLYCOLYSISAdapted from Coffee, 1998.

Adenylate cyclase

Hypothalamus

CRF

Pituitary

ACTH

Adrenal Cortex

Adrenal Medulla

Central Nervous System

Cortisol Liver

Glycogen

Muscle

Glycogen

Epinephrine

Muscle

Glycogen

STRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic HormoneAdapted from Classen and Porta, 1996.

Hypothalamus

CRF

Pituitary

ACTH

Adrenal Cortex

Adrenal Medulla

Central Nervous System

Cortisol Liver

Glycogen

Muscle

Glycogen

Epinephrine

Muscle

Glycogen

STRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic HormoneAdapted from Classen and Porta, 1996.

Nervous Stimulation

Adapted from Coffee, 1998.

Sarcoplasmic Reticulum

Ca

Ca

Ca Ca

Ca

Ca

Ca

Ca

Ca

Ca

Nervous Stimulation

Ca2+

Adapted from Coffee, 1998.

Nervous Stimulation

Ca2+

Troponin-CCa2+

Adapted from Coffee, 1998.

Nervous Stimulation

Ca2+

Troponin-CCa2+

Muscle Contraction

Adapted from Coffee, 1998.

Nervous Stimulation

Ca2+

Troponin-CCa2+

Muscle Contraction

Lactic Acid

pHAdapted from Coffee, 1998.

Nervous Stimulation

Ca2+

Troponin-CCa2+

Muscle Contraction

Phosphorylase kinase-Ca2+

Lactic Acid

pHAdapted from Coffee, 1998.

Nervous Stimulation

Ca2+

Troponin-CCa2+

Muscle Contraction

P

Glycogen Phosphorylase

Phosphorylase kinase-Ca2+

Glycogen Phosphorylase

Lactic Acid

pHAdapted from Coffee, 1998.

Nervous Stimulation

Ca2+

Troponin-CCa2+

Muscle Contraction

P

Glucose-1-phosphate

Glycogen Phosphorylase

Phosphorylase kinase-Ca2+

Glycogen Phosphorylase

Glycogen

GLYCOLYSISLactic Acid

pHAdapted from Coffee, 1998.

Nervous Stimulation

Ca2+

Troponin-CCa2+

Muscle Contraction

P

Glucose-1-phosphate

Glycogen Phosphorylase

Phosphorylase kinase-Ca2+

Glycogen Phosphorylase

Glycogen

GLYCOLYSIS

Ca2+-calmodulin-protein kinase

Lactic Acid

pHAdapted from Coffee, 1998.

Nervous Stimulation

Ca2+

Troponin-CCa2+

Muscle Contraction

P

Glucose-1-phosphate

Glycogen Phosphorylase

Phosphorylase kinase-Ca2+

Glycogen Phosphorylase

Glycogen

GLYCOLYSIS

Ca2+-calmodulin-protein kinase

Glycogen Synthase

Glycogen Synthase P

Lactic Acid

pHAdapted from Coffee, 1998.

Nervous Stimulation

Ca2+

Troponin-CCa2+

Muscle Contraction

P

Glucose-1-phosphate

Glycogen Phosphorylase

Phosphorylase kinase-Ca2+

Glycogen Phosphorylase

Glycogen

GLYCOLYSIS

Ca2+-calmodulin-protein kinase

Glycogen Synthase

Glycogen Synthase P

Lactic Acid

pHAdapted from Coffee, 1998.

Glycogen Storage

Hypothalamus

CRF

Pituitary

ACTH

Adrenal Cortex

Adrenal Medulla

Central Nervous System

Cortisol Liver

Glycogen

Muscle

Glycogen

Epinephrine

Muscle

Glycogen

STRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic Hormone

Mg inhibits

Adapted from Classen and Porta, 1996.

Hypothalamus

CRF

Pituitary

ACTH

Adrenal Cortex

Adrenal Medulla

Central Nervous System

Cortisol Liver

Glycogen

Muscle

Glycogen

Epinephrine

Muscle

Glycogen

STRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic Hormone

Mg inhibits

Adapted from Classen and Porta, 1996.

Hypothalamus

CRF

Pituitary

ACTH

Adrenal Cortex

Adrenal Medulla

Central Nervous System

Cortisol Liver

Glycogen

Muscle

Glycogen

Epinephrine

Muscle

Glycogen

STRESS

CRF- Corticotropin Releasing Factor

ACTH-Adrenocorticotrophic Hormone

Mg inhibits

Adapted from Classen and Porta, 1996.

Nervous Stimulation

Adapted from Coffee, 1998.

Sarcoplasmic Reticulum

Ca

Ca

Ca

Ca

Ca

Ca

Mg

Ca

Ca

Ca

Mg

Mg

Mg

Mg

Mg

Mg

MgMg

Mg

Mg

Nervous Stimulation

Ca2+

Troponin-CCa2+

P

Glucose-1-phosphate

Glycogen Phosphorylase

Phosphorylase kinase-Ca2+

Glycogen Phosphorylase

Glycogen

GLYCOLYSIS

Ca2+-calmodulin-protein kinase

Glycogen Synthase

Glycogen Synthase P

Muscle Contraction

Adapted from Coffee, 1998; Fry and Hall, 1996.