Abstract

Studies were designed to determine die relationship between acute hypocalcemia obtained with ethylene-glycol-bis (α-aminoethyl-ether)-N,N'tetraacetate (EGTA) infusions and im-munoreactive PTH (iPTH) responses seen in cows. In addition, the sensitivity and the rapidity of the iPTH responses were evaluated. During EGTA infusions the plasma ionized calcium decreased in proportion to the total calcium (Ca), whereas the magnesium did not change. A significant response of 0.2 ng⁄ml iPTH (Δ4–8 min, p < 0.02) was already observed with a A Ca of 0.1 mg⁄100 ml (Δ4-8 min, p < 0.005). The magnitude of the early iPTH responses was determined by decrements of Ca of up to 1.2 mg/100 ml (A4-8 min). When the Δ Ca 4-8 min was greater, peak iPTH responses did not rise further. The total incremental iPTH output (ng/ml × min) was also increased in a nonlinear manner to the total decremental change of Ca (mg/100 ml × min). After subtraction of the circulation-time (measured by Evans Blue), iPTH started to rise at 20 sec or les...

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.