Exercise-induced changes of endorphin contents in hypothalamus, hypophysis, adrenals and blood plasma.
Changes of alpha-, beta-, and gamma-endorphin contents were determined in hypothalamus, hypophysis, adrenals and blood plasma in Wistar rats. Four hours of swimming in water at 32 +/- 1 degrees C caused a decrease of the beta-endorphin content in hypophysis and hypothalamus. In adrenals, beta-endorphin did not change. Changes of alpha- and gamma-endorphins were not parallel to alterations of beta-endorphin. In blood plasma, levels of both alpha- and gamma-endorphins were elevated. After 7 days of swim training, 4 hours of swimming caused a slight increase of alpha-, beta- and gamma-endorphin levels in hypophysis as well as a pronounced increase of alpha- and beta-endorphins in adrenals. In hypothalamus, beta-endorphin content was decreased, but alpha-endorphin content was on the level of sedentary controls, gamma-endorphin content doubled. The levels of endorphins in blood were higher than after a single swimming bout. It was concluded that during acute exercise the activation of the opioid system is mainly based on the augmented release of beta-endorphin. In daily repeated exercise the production of beta-endorphin increases and exceeds the elevated release in hypophysis and adrenals.
Tendzegolskis
Z
Z
Department of Sports Physiology, Tartu University.
Viru
A
A
Orlova
E
E
D000311:Adrenal Glands / Q000737:chemistry*; D000818:Animals; D004723:Endorphins / Q000097:blood* / Q000378:metabolism; D007031:Hypothalamus / Q000737:chemistry*; D005082:Physical Exertion / Q000502:physiology*; D010902:Pituitary Gland / Q000737:chemistry*; D051381:Rats; D011919:Rats, Inbred Strains; D013550:Swimming; D001615:beta-Endorphin / Q000378:metabolism
D004723:Endorphins; D001615:beta-Endorphin