Changes in the levels of different ions in the eggshell gland lumen following p,p'-DDE-induced eggshell thinning in ducks.
Eggshell thinning in ducks was induced by administration of p,p'-DDE in the diet (40 mg/kg food) for 45 days. This treatment resulted in a 19% reduction of the Eggshell Index (EI). Shells from calcifying eggs obtained at the time of slaughter showed a 36% reduction of EI. Prostaglandin synthesis by a homogenate of eggshell gland mucosa from p,p'-DDE-treated ducks was reduced by 24%. HCO3(-)-stimulated ATPase activity by a homogenate of eggshell gland mucosa from p,p'-DDE-treated ducks was not significantly changed. The calcium content of eggshell gland mucosa was increased to 127% in p,p'-DDE-treated ducks. p,p'-DDE-treated ducks showed profound changes in the shell gland luminal content of several ions. Calcium (-43%), sodium (-15%), potassium (-15%), bicarbonate (-33%) and chloride (-29%) were all significantly reduced in p,p'-DDE-treated ducks. The content of phosphate was unchanged. These findings are discussed in relation to a proposed mechanism for p,p'-DDE-induced eggshell thinning that involves inhibition of prostaglandin synthesis in eggshell gland mucosa.
Lundholm
C E
CE
Department of Pharmacology, Faculty of Health Sciences, University of Linköping, Sweden.
D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors; D000818:Animals; D027321:Anion Transport Proteins; D001639:Bicarbonates / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002712:Chlorides / Q000378:metabolism; D003633:Dichlorodiphenyl Dichloroethylene / Q000494:pharmacology*; D004372:Ducks / Q000502:physiology*; D004528:Egg Shell / Q000033:anatomy & histology / Q000737:chemistry / Q000187:drug effects*; D005088:Exocrine Glands / Q000187:drug effects / Q000378:metabolism*; D009092:Mucous Membrane / Q000187:drug effects / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D011453:Prostaglandins / Q000096:biosynthesis; D012964:Sodium / Q000378:metabolism
D027321:Anion Transport Proteins; D001639:Bicarbonates; D002712:Chlorides; D010710:Phosphates; D011453:Prostaglandins; D003633:Dichlorodiphenyl Dichloroethylene; D012964:Sodium; D000251:Adenosine Triphosphatases; C031652:anion-sensitive ATPases; D011188:Potassium; D002118:Calcium