Furosemide decreases eggshell thickness and inhibits 45Ca2+ uptake by a subcellular fraction of eggshell gland mucosa of the domestic fowl.
1. Administration of furosemide to egg-laying domestic fowl (single p.o. dose 100 mg/bird) caused a decrease in the thickness of the shell of eggs laid the next day. 2. Furosemide administration in vivo caused a 37% decrease in the uptake of 45Ca2+ by a subcellular fraction of the eggshell gland mucosa (mainly composed of cell fragments and plasma membranes). 3. Furosemide treatment did not affect calcium concentrations in plasma or shell gland fluid but did cause a significant increase in the calcium concentration in shell gland mucosa. 4. It is concluded that the eggshell-thinning effect of furosemide is localized to an inhibitory effect on plasma membrane calcium transport in the eggshell gland mucosa. 5. These findings are discussed and compared with the effects of other drugs and toxic substances known to influence eggshell formation in birds.
Department of Pharmacology, University of Linköping, Sweden.
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Lundholm
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Bartonek
D000818:Animals; D002118:Calcium / Q000097:blood / Q000378:metabolism*; D002132:Calcium Radioisotopes; D002645:Chickens / Q000378:metabolism*; D004528:Egg Shell / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism; D005088:Exocrine Glands / Q000187:drug effects / Q000378:metabolism*; D005260:Female; D005665:Furosemide / Q000494:pharmacology*; D009092:Mucous Membrane / Q000187:drug effects / Q000378:metabolism
D002132:Calcium Radioisotopes; D005665:Furosemide; D002118:Calcium