Related Experiment Video
Updated: Aug 17, 2026

Evaluation of Mammary Gland Development and Function in Mouse Models
Published on: July 21, 2011
Catecholamines, oxytocin and milk removal in dairy cows
J W Blum1, D Schams, R Bruckmaier
1Institute of Animal Science, Federal Institute of Technology, Zürich, Switzerland.
Abstract:
Experiments were designed to study the effects of catecholamines on oxytocin responses and milk removal in dairy cows. Adrenalin, noradrenalin, dopamine, isoproterenol (a beta-adrenoceptor agonist), phentolamine (an alpha-adrenergic blocker) and propranolol (a beta-adrenergic blocker) were infused intravenously. In addition, adrenalin was infused together with phentolamine and/or propranolol. Infusions started 8 min before milking and lasted until the end of milking. In some cases electroshocks (for 5 s) were applied immediately before milking in the absence and presence of phentolamine and propranolol. Adrenalin, noradrenalin and dopamine reduced milk removal, but only if administered in supraphysiological amounts. The effect of adrenalin and electroshocks on milk removal could be inhibited only partly by phentolamine. Inhibition of milk removal was not mediated by reduced oxytocin responses. Enhanced local release of catecholamines from sympathetic nerves was presumably responsible for lowered milk removal in response to electroshocks. Milk removal was facilitated during alpha-adrenergic blockade and during beta-adrenoceptor stimulation.
Related Concept Videos
Hormonal Regulation
Feedback Loops
Regulation of Hormone Secretion
Humoral stimuli,...
The Mammary Glands
Each breast features a pigmented projection known as the nipple, through which milk emerges via closely spaced openings of ducts, referred to as lactiferous ducts. Surrounding the nipple is a circular pigmented area of skin named the areola, which appears rough due to...
Neurotransmitters
Major Hormones and Their Functions
Oxytocin, produced in the hypothalamus and released by the pituitary gland, plays a role in social bonding, childbirth, and lactation.

