Catecholamines
- Epinephrine and Norepinephrine
- Epinephrine is an adrenal hormone (AKA: Adrenalin)
- Norepinephrine is nitrogen-containing neurotransmitter (AKA:
Noradrenalin)
- found in parts of the sympathetic and central nervous system
- Responds to 'Fight or Flight'
- Act through adrenergic receptors
- alpha-1, alpha-2, beta-1, beta-2, beta-3
- Increased gluconeogenesis in liver
- Increased glycogenolysis in liver and muscle
- Increased lipolyisis in adipose tissue
- Epinephrine
- induces muscle anaerobic glycolysis
- increases lipolysis but decreases fat oxidation so that overall
effect may be an increase in body fat (Coyle Ed, Austin Group
2004)
Cortisol
- Blood sugar regulation
- Anti-inflammatary action
- Immune response modification
- Heart and blood vessel toning
- Central nervous system stimulation
- Stress reaction normalization
Cortisol is a catabolic hormone which induces the breakdown
of cellular proteins. Cortisol helps maintain plasma glucose
levels during a fast by stimulating gluconeogenesis / lipolysis
and inhibing lipid synthesis. Glucocorticoides decrease muscle
protien synthesis and increase muscle protein degradation so
amino acids will be available for glucose production. Cortisol
also increases lipolysis, in part, by enchancing GH and catecholamine
stimulated lipolysis. In men, significant elevations in cortisol
seem to reduce endongenous testosterone by acting directly upon
the testis to impair the biosynthesis of testosterone (Di Pasquale,
1992c).
Cortisol increases as intense exercise is prolonged (Di Pasquale,
1992c). Submaximal exercise at lower intensities (i.e. 63% maximum
oxygen consumption) stimulates lower cortisol response than higher
intensities (i.e. 86% maximum oxygen consumption) (Farrell, Garthwaite,
& Gustafson, 1983; Naveri, 1985).
Aldosterone
- Regulation of sodium, otassium and fluid volume
- Increase of aldosterone results in sodium and water retention
and potassium excreation
- Keeps blood pressure from falling
- Maintains electrolyte balance and cell hydration
DHEA
Dehydroepiandrosterone is steroid prohormone produced from
cholesterol by the adrenal glands, the gonads, adipose tissue,
brain and in the skin (by an autocrine mechanism). DHEA is the
precursor of androstenedione which can undergo further conversion
to produce testosterone and estrogens.
Androgens
See Testosterone
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