D2-dopaminergic blockade does not influence post-exercise ketosis in non-athletes.
Metoclopramide has previously been shown to inhibit the ketosis of starvation in rats and humans. The effect of D2-dopaminergic blockade on post-exercise ketosis was, therefore, studied in 6 carbohydrate-starved non-athletic persons who had just completed a 9-km walk in mountainous terrain. There were nine control subjects who went on the walk, but who did not ingest metoclopramide. Metoclopramide (0.15 mg.kg-1 body mass) caused a highly significant rise in the plasma prolactin concentration, but did not influence blood concentrations of 3-hydroxybutyrate, free fatty acid, glucose, insulin or glucagon. Unlike ketosis in starvation, therefore, neither prolactin, nor the D2-dopaminergic system play a part in the genesis of post-exercise ketosis.
Vahed
Y A
YA
Department of Physiology, Medical School, University of Cape Town, Observatory, South Africa.
Koeslag
J H
JH
Lochner
J V
JV
D020155:3-Hydroxybutyric Acid; D000138:Acidosis / Q000517:prevention & control*; D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D005934:Glucagon / Q000097:blood; D006801:Humans; D006885:Hydroxybutyrates / Q000097:blood; D007328:Insulin / Q000097:blood; D007662:Ketosis / Q000517:prevention & control*; D008297:Male; D008787:Metoclopramide / Q000494:pharmacology* / Q000627:therapeutic use; D005082:Physical Exertion / Q000187:drug effects*; D011388:Prolactin / Q000097:blood
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D005230:Fatty Acids, Nonesterified; D006885:Hydroxybutyrates; D007328:Insulin; D011388:Prolactin; D005934:Glucagon; D008787:Metoclopramide; D020155:3-Hydroxybutyric Acid