Histochemical Observations on the Lipid Changes in Rat Corpora Lutea During Various Reproductive States After Treatment With Exogenous Hormones

Abstract

Lipid changes were studied histochemically in rat CL during the oestrous cycle, pregnancy and lactation after treatment with oestradiol benzoate (EB), LH and prolactin. A single injection of 50 mug EB given on any day during the first half of the oestrous cycle, pregnancy and lactation caused a heavy accumulation of lipid droplets, which consisted mainly of cholesterol and/or its esters, triglycerides and some phospholipids. If the treatment with EB was followed by a single injection of 20 i.u. prolactin, droplet accumulation either did not occur, or was greatly reduced. During the second half of pregnancy, a massive accumulation of cholesterol- and triglyceride-positive lipid droplets occurred in the CL of untreated rats, and prolactin was equally effective in reducing, or preventing the storage of cholesterol-positive lipid droplets. Prolactin was more effective if two injections of 10 i.u. were given daily after an interval of 11 to 12 hr. No appreciable lipid change in the CL was caused by injection of 100 mug LH on any day during the first half of the oestrous cycle and pregnancy, but during lactation the same amount caused a heavy accumulation of lipid droplets, consisting mainly of cholesterol and/or its esters, triglycerides and very little phospholipid. Persisting CL of pregnancy and cyclic CL seen during lactation and pregnancy, respectively, were unresponsive to exogenous hormones, apparently due to ageing as no lipid changes occurred in the CL after hormonal treatment. The results are discussed in relation to previous histochemical and biochemical studies and suggest that both LH and prolactin regulate the lipid and cholesterol metabolism in the luteal cells of the rat.

Histochemical Observations on the Lipid Changes in the Ovarian Interstitial Gland Tissue of Rats

“…Their experiments, however, did not eliminate the possibility of stimula¬ tion of progesterone production in the rat CL by prolactin. It has been shown that LH and prolactin act synergistically to regulate the metabolism of choles¬ terol-and triglyceride-containing lipid droplets in the rat CL (Guraya, 1975b), but this does not seem to be true for the interstitial tissue which responds mainly to LH only. It is well established that the depletion of cholesterol-containing lipid drop¬ lets from the interstitial tissue of the rabbit ovary in response to both endo¬ genous and exogenous LH is related to the production of progestins.…”

Συμβολη Εις Την Μελετην Των Λιπιδιακων Μεταβολων Επι Κυησεως

“…1975) καί έλαττοΰνται μόνον κατά τό τέλος αυτής. Ίστοχημικαί καί βιοχημικαί μελέται κατέληξαν δτι ή LH καί ή προλακτίνη ρυθμίζουν τόν μεταβολισμόν της χοληστερόλης καί τών άλλων λιπιδίων εντός τών κυττάρων τών ποντικών(Guraya 1975).AL διαταραχαί τοϋ μεταβολισμού των λιπιδίων καί των υδατανθράκων επιδρούν εις τήν πρόκλησιν ατυχημάτων της εμ βρυϊκής αναπτύξεως. *Υπερλιπαιμικαί καταστάσεις πού προεκλήθησαν διά τοϋ Triton Wr 1339 έδειξαν περισσοτέρας βλάβας έκ της υπογλυκαιμίας, διά τήν έκβασιν της κυήσεως καί τήν άνάπτυξιν τοϋ εμβρύου(Tuchmann Duplessis 1974).…”