Plasma beta-endorphin and adrenocorticotrophin in young horses in training.

R. N. McCarthy, L. B. Jeffcott, J. W. Funder, M. Fullerton, I. J. Clarke

Research output: Contribution to journalArticleResearchpeer-review

Abstract

A controlled period of submaximal exercise on a treadmill was used as a standardised stress test in 6 young horses to monitor the effects of training. Circulating plasma concentrations of immunoreactive beta-endorphin (IR beta-EP) were measured before, during and after the exercise period. The stress test was conducted on 3 occasions during an intensive training program lasting 14 weeks. In week 3 a marked increase in plasma IR beta-EP (P = 0.003) was demonstrated as a result of training, but by the last exercise test performed in week 9 no significant increase in plasma IR beta-EP concentrations could be detected. During the training period the basal concentrations of plasma IR beta-EP significantly decreased (P = 0.0059). Plasma adrenocorticotrophin (ACTH) did not increase during exercise, although there was a trend of decreasing basal plasma ACTH by the end of the training period. It was concluded that a standardised work test acted as a mild stress to unfit horses, but as the horses' fitness increased the hormonal response to exercise diminished. Basal plasma beta-EP concentrations were decreased with increasing fitness.

Original languageEnglish
Pages (from-to)359-361
Number of pages3
JournalAustralian Veterinary Journal
Volume68
Issue number11
DOIs
Publication statusPublished - 1 Jan 1991
Externally publishedYes

Cite this

McCarthy, R. N. ; Jeffcott, L. B. ; Funder, J. W. ; Fullerton, M. ; Clarke, I. J. / Plasma beta-endorphin and adrenocorticotrophin in young horses in training. In: Australian Veterinary Journal. 1991 ; Vol. 68, No. 11. pp. 359-361.
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Plasma beta-endorphin and adrenocorticotrophin in young horses in training. / McCarthy, R. N.; Jeffcott, L. B.; Funder, J. W.; Fullerton, M.; Clarke, I. J.

In: Australian Veterinary Journal, Vol. 68, No. 11, 01.01.1991, p. 359-361.

Research output: Contribution to journalArticleResearchpeer-review

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