PLASTICITY OF FIBER TYPE EXPRESSION OBJECTIVES (I and II) Methodology: Methodology: Electrophysiology: resting Em and action potential Electrophysiology: resting Em and action potential Measurement of ion channel activity Measurement of ion channel activity Source of information Source of information Role of : Role of : Calcineurin Calcineurin nFAT nFAT Nitric oxide (NO) Nitric oxide (NO) NOR-1 NOR-1

INTRODUCTION

CALCINEURIN CATALYTIC DOMAIN CaM- Binding domain Auto- Inhibitory Domain Calcineurin A (CNA)

CALCINEURIN AND NFAT PATHWAY IN B- LYMPHOCYTES

CALCINEURIN-NFAT Pathway

CALCINEURIN INCREASES mRNA LEVELS FOR MYOGLOBIN, SLOW TnI AND SARCOMERIC MITOCHONDRIAL CREATINE KINASE IN GASTROCNEMIUS MUSCLE

CALCINEURIN DECREASES mRNA LEVELS FOR PARVALBUMIN AND MUSCLE CREATINE KINASE IN GASTROCNEMIUS MUSCLE

FIRING PATTERNS IN MUSCLE

FIRING PATTERNS vs. FORCE-FREQUENCY CURVE IN MUSCLE

Ca 2+ TRANSIENT IN SLOW AND FAST FIBERS

DISCUSSION

ACTIVATION OF NF- Ќ B, JNK1 AND NFAT IN B-LYMPHOCYTES

ACTIVATION OF NF- Ќ B, JNK1 AND NFAT IN Ca 2+ spike vs. prolonged elevation

ACTIVATION OF NF- Ќ B, JNK1 AND NFAT IN small prolonged elevation of Ca 2+

ACTIVATION OF NF- Ќ B, JNK1 AND NFAT IN Ca 2+ dose-response curve

MUSCLE OVERLAOD CAUSES A CALCINEURIN DEPENDENT HYPERTROPHY

MUSCLE OVERLAOD CAUSES A CALCINEURIN DEPENDENT INCREASE IN TYPE I FIBERS

MUSCLE OVERLAOD CAUSES A CALCINEURIN DEPENDENT CHANGE IN mRNA OF MHC AND TnI

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