Ma. Henault et Gj. Killian, SYNTHESIS AND SECRETION OF LIPIDS BY BOVINE OVIDUCT MUCOSAL EXPLANTS, Journal of Reproduction and Fertility, 98(2), 1993, pp. 431-438
The objectives of this study were to determine the types of lipid synt
hesized and secreted by the bovine oviduct, and to determine whether l
ipid synthesis and secretion varied with stage of the ovarian cycle an
d oviductal region. Oviduct explant cultures were prepared from cows k
illed during either the follicular or luteal stage of the oestrous cyc
le. Both stage of ovarian cycle and oviductal region affected lipid sy
nthesis by oviductal explants in vitro. More lipid was synthesized by
explants from follicular than from luteal-stage cows. Ampullar explant
s synthesized the greatest quantity of total lipid, followed by the pr
eampulla and isthmus. Separation of extracted lipids from cultured tis
sue by high performance thin-layer chromatography (HPTLC) resolved pho
sphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosph
atidylinositol, cardiolipin, free cholesterol, free fatty acid, trigly
ceride and esterified cholesterol, all of which were synthesized durin
g culture. The ampulla synthesized significantly more phosphatidyletha
nolamine, phosphatidylserine and phosphatidylinositol than did the oth
er regions. Culture supernatants from ampullary explants contained the
most newly synthesized cholesterol when compared with other regions.
The histochemical location of neutral lipid droplets in the epithelium
of cultured explants paralleled the localization of radioactivity in
autoradiographs of explant extracts. The results suggest that the ovid
uct synthesizes a variety of lipids, and that some of these are releas
ed into culture supernatants.