Pronase reduces intramembranous particle density in uterine epithelial cells in vivo

The proteolytic enzyme, pronase, was injected into the uterine lumen of rats. This treatment removed half the intramembranous particles (IMPs) from the apical plasma membrane of the uterine epithelial cells but tight junctions of these cells were unaffected. We conclude that at least some of the IMPs are proteinaceous in nature and suggest that IMPs not affected by pronase may be deeply embedded in the lipid bilayer.     

Clomiphene citrate alters vaginal surface morphology in cycling rats.

Cycling virgin female rats were treated with clomiphene citrate (CC) during dioestrus of the reproductive cycle. Animals were sacrificed 2 days after the initial injection and their vaginal tissue was examined by scanning electron microscopy. Animals treated with one dose of CC had an epithelium consistent with a prolonged dioestrus. Treatment with CC for 2 days induced changes in the epithelium that had no resemblance to any normal hormonally controlled event in the vagina. It was found that CC had effects consistent with progesterone alone as well as effects unique to this superovulatory drug.     

Ultrastructure and elemental composition of dormant and germinating Diplodia maydis spores.

The ultrastructure of Diplodia maydis spores was studied in thin sections with a transmission electron microscope. Storage vacuoles were evenly distributed in the two cells. Some of the vacuoles that contained a dense osmiophilic sphere(s) were surrounded by a membrane, and had membranous aggregates around their periphery. The sport wall was composed of an electron-dense layer and an electron-translucent layer. An inner cytoplasmic membrane was present. Dormant and germinating spores were studied with scanning electron microscopy and also with a Si (Li) energy-dispersive X-ray analyzer. The dormant spore was ovate and usually two-celled with a central septum. Germination proceeded via a germ tube from the side of one end of the cell. Of several methods for preparation of specimens for X-ray analysis studied, freeze-dried spores mounted on carbon stubs and then further carbon coated gave the best results. X-ray analyses revealed that spore populations contained large amounts of Si, P, Cl, and K, smaller amounts of S and Ca, and trace amounts of Mg and Al. Analyses of single spores revealed high K and Cl and low P and Mg at one end of the cell with concomitant low K and Cl and high P and Mg in the central portion and other end of the cell. In two-celled germinating spores, high K and Cl occurred in the end of the nongerminating spore cell, whereas the germinating cell contained high P and Mg and low K and Cl. X-ray image maps revealed that K and Cl were located together at one end of the spore.