Effect of prazosin on the function of the teat sphincter in lactating cows
Autor: | Georgette Vandeputte-Van Messom, Georges Peeters, Christian Burvenich, Jacques Bernabé |
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Rok vydání: | 1984 |
Předmět: |
animal structures
Muscle Relaxation Oxytocin Milking Mammary Glands Animal fluids and secretions Animal science Pregnancy Jugular vein Prazosin medicine Animals Lactation Plethysmograph Milk Ejection Udder business.industry food and beverages Muscle Smooth General Medicine Plethysmography medicine.anatomical_structure Injections Intra-Arterial Injections Intravenous Quinazolines Sphincter Cattle Female Animal Science and Zoology business Food Science medicine.drug Artery |
Zdroj: | Journal of Dairy Research. 51:219-226 |
ISSN: | 1469-7629 0022-0299 |
DOI: | 10.1017/s0022029900023475 |
Popis: | SummaryOxytocin was infused for 60 min into the jugular vein of 8 lactating cows with full udders before milking. Under these circumstances milk loss occurred spontaneously in 3 cows and was evoked in 5 cows by reducing pressure around one teat (–30 cm water) using a plethysmographic chamber. Milk loss was measured continuously. The postsynaptic α-blocking agent prazosin (PRZS) injected either into the udder artery (2 or 5 mg) or into the jugular vein (200 mg) consistently induced a significant increase in milk leakage. It is suggested that PRZS effectively inhibits α-adrenoceptors in the teat sphincter muscles and thus promotes the action of β-adrenoceptors, in this way inducing relaxation of the teat sphincter. |
Databáze: | OpenAIRE |
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