Bovine Pituitary LH and Prolactin Release During Superfusion in Vitro

Abstract

Summary

Explants were taken from central and peripheral regions of the anterior pituitary, cut into small (1 × 1 × 2 mm) or large (1 × 1 × 10 mm) pieces, and incubated by continuous superfusion in TC-199 with 0.035 or 0.224% NaHCO₃ for 6 hr. Explants from cows released 137% more LH than those from steers but 65% less prolactin. Average LH concentration 2 and 6 hr postculture was 49% greater in explants from cows. Prolactin release but not LH release was greater into medium containing 0.224% than 0.035% NaHCO₃ and postculture concentration in the pituitary tissue inversely reflected this pattern. Release and postculture tissue concentration of LH and prolactin was greatest for explants from the central and peripheral pituitary regions, respectively. Explant size did not influence release of prolactin or LH but release of both hormones was increased significantly during the incubation period.