The fine structure of sow lutein cells

Abstract

The morphological observations described in this reuort are part of a biochemical study of progesterone intermediates using sow ovary. This tissue is extensively involved in the production of some steroid hormones. Because the lutein cells are thought to be involved in the synthesis of progesterone and its intermediates and because these cells constitute by size and number the greatest portion of the mass of sow ovary, we confined the morphological investigation to these cells. Sow corpora lutea, fixed with glutaraldehyde and osmium tetroxide were examined by light and electron microscopy.The lutein cells of the sow are large epithelioid cells with oval nuclei and extensive amounts of cytoplasm. Large masses of highly organized smooth endoplasmic reticulum, many oval mitochondria with tubular cristae, and many lipid droplets are present. Only a few profiles of rough endoplasmic reticulum are seen in any one section, and Golgi membranes cannot by distinguished from other smooth membranes. The smooth endoplasmic reticulum is the major membranous organelle in these luteal cells. Microsomal preparations from luteal cells must be very rich in fragments of these smooth membranes. The demonstration of many steroidogenic enzyme systems in microsomal preparations lends strong support to the supposition that these enzyme systems reside in the smooth endoplasmic reticulum.Christensen ('65) has drawn attention to the unusual amount and organization of the smooth endoplasmic reticulum in the interstitial cells of guinea pig testes. This report, an adjunct to a biochemical investigation of the metabolism of progesterone in the sow ovary, deals with some ultrastructural observations of several sow lutein cells.Smooth membranes isolated from the microsomal fraction of sow ovary homogenates by density gradient fractionation (Fouts, '61) were used in studying some intermediary products in the metabolism of progesterone. One of the authors (B.K.) noting the yield of the smooth membrane fraction was greater than expected asked that the purity of the preparation be confirmed by electron microscopy. Subsequent observations of several pellets confirmed the presence of smooth membranes with no contaminating ribosomes, mitochondria1 fragments or nuclei. In addition biochemical checks or purity were performed. The yield of relatively clean smooth membranes in greater quantities than was expected prompted this morphological study on the intact ovary.We consider the extensive mass of highly organized smooth membranes, and ANAT. REC., 161: 77-90.the associated mass of mitochondria and lipid are worthy of description. In addition this report contains a description of a single, highly unusual nucleus that contains an intranuclear membranous system. MATERIALS AND METHODSThe ovaries utilized in this study were collected under the same conditions as those used in the biochemical investigation save that tissues from non-pregnant and pregnant sows were collected separately. At this time only tissues from the non-pregnant animals have been ...

Comparative morphological and histochemical observations on the ovarian stromal compartment in mammals with special reference to steroidogenesis

“….. 277 terized by their content of abundant agranular endoplasm ic reti culum, lipid droplets, m itochondria with tubular cristae, dense bodies, and Golgi apparatus, i.e., similar to cells involved in the production of steroid hormones. Recently, correlated morphological and biochemical studies have shown th at the m em branes of the agranular endoplasmic reticulum (or diffuse lipoproteins) play large roles as sites for enzymes involved in steroidogenesis [see Christen sen , 1965;Christensen and Fawcett, 1966;Goodman et al, 1968;G uraya, 1968a,b,c, 1969aFawcett etal., 1969;Christensen and Gillim, 19691; the Leydig cells of the mouse testis, which contain abundant diffuse lipoproteins (figs.25, 26), also show abundant m em branes of sm ooth reticulum [Christensen and F awcett, 1966], further confirming that the former are derived from the latter. In addition to acting as a site for the synthetic enzymes involved in the biosynthesis of steroids, the diffuse lipoproteins (or m em branes of agranular endoplasmic reticulum) of steroid gland cells may also accum ulate and store cholesterol as a com ponent of I heir lipids which is now well known to act as the precursor for the biosynthesis of steroid hormones [Guraya, 1968a[Guraya, ,b,c, 1969a[Guraya, , 1971Goodman et al, 1968: Christensen andGii.lim, 1969;Fawcett et al, 1969).…”

Histochemical observations on the granulosa (follicular) cells in the preovulatory and postovulatory follicles of garden lizard ovary

“…1967;Bjersin g , 1967a;P riedkalns and W eb er , 1968;G illim et til.. 1969;Fawcett et ul.. 1968;Goodman et al, 1968: Davies and Broadus, 1908. Similar develop ment of agranular endoplasm ic reticulum in the granulosa cells of the postovulatory follicles has been described recently in the hen [Wyburn el al., 1966] and Amphibia [Kessel and Panje 19681. iii l In-preovulatory and postovulatory follicles of garden lizard ovary 573 Gl'RAYA 11971, 1972a, b, c|, aftei making correlations in the find ings of histochcm ical and electron microscopic studies on the granu losa luteal cells in Mammalia, has suggested that the diffusely distrib uted lipoproteins of histochemical studies derive from the ultrastructural agranular endoplasmic reticulum .…”

“…However, Guraya 11971 ] in bis most recent review article has discussed in detail the im portance and physiological significance of diffusely distributed sudanophilic lipoproteins in the granulosa luteal cells as yvell as in other steroidsecreting cells of mammals. Correlated morphological and bio chemical studies have shown th a t the m embranes of agranular endoplasmic reticulum , constituted by the diffusely distributed lipoproteins, play an im portant role as sites for enzymes involved in steroidogenesis [Christensen, 1965;Christensen and Fawcett, 1966;Goodman et «/., 1968Goodman et «/., : F ayvcett et «/.. 1969G uraya, 1971;Christensen and Gillim, 1969]. This is strongly supported by the correlations made in the findings of cytological and histochemical studies by Gi RAYA [1971,1972 a, b, c], which have clearly shown th at the activities of enzymes involved in the biosynthesis of steroid hor mones parallel the presence and developm ent of diffuse lipoproteins (or agranidar endoplasmic reticulum ) in the luteal cells, theca interna cells, and interstitial gland cells.…”

“…The diffuse lipoproteins dem onstrated histocheniicallv might hind a sufficient am ount of cholesterol for use as a substrate for steroid synthesis [Christensen, 1965;Goodman et al, 1968;F awcett et al, 1969;Christensen and Gillim, 1969;Guraya, 1971Guraya, , 1972a d|. This masked cholesterol could not he dem onstrated with the Schultz test.…”

Comparative studies on the histochemical features of ovarian compartments in the rat and golden hamster, with special reference to steroid hormone synthesis

“…1968;Fawcett et al, 1969;Christensen and Gillim, 1969]. It can be assum ed th a t the diffuse lipoproteins dem onstrated histochemically derive from the extensively developed smooth reticulum which acts as a site of enzymes involved in the produc tion of steroid horm ones [Christensen, 1965;Christensen and Fawcett, 1966;Goodman et al, 1968: Fawcett et al, 1969 Chris tensen and Gili.im, 1969]. Histochemical studies have dcm onslraed the presence of various enzymes in the cells of the theca interna, interstitial gland tissue and corpus luteum of rat and ham ster, which are involved in the biosynthesis of steroid hormones | Levy et al, 1959;Taylor, 1961; R ubin et al, 1963 and Balogh.…”