Hepatitis B Virus (HBV)

Tag: Progesterone

Stimulation of Xenopus laevis Oocyte Maturation: DISCUSSION

Me-p-CD has been used extensively as a pharmacological tool to deplete cellular cholesterol, disrupt cholesterolrich membrane domains, and investigate coincident changes in signaling phenomena and cellular responses. In cultured mammalian cells, 5-100 mM cyclodextrin has been used, and longer exposure to high concentrations is sometimes toxic to cells. Therefore, the toxic response observed in some […]

Stimulation of Xenopus laevis Oocyte Maturation: RESULTS

To test the effect of cholesterol depletion on the time course of progesterone-induced GVBD, groups of 25-30 oocytes were incubated in increasing concentrations of Me-p-CD in Ringers-HCO3 at room temperature for 4 h, washed, and incubated with 1.5 |xM progesterone. Treatment of oocytes with concentrations of Me-p-CD <5 mM had no apparent effect on the […]

Stimulation of Xenopus laevis Oocyte Maturation: MATERIALS AND METHODS

Experimental Animals and Oocyte Isolation Mature Xenopus laevis females (Xenopus I, Dexter, MI) were housed in aquatic tanks in a temperature controlled room at 16°C, fed ground beef twice weekly, and maintained on daily cycles of 14L:10D. Frogs were primed by injection of 35 IU of eCG (PmSg; Calbiochem, La Jolla, CA) into the dorsal […]

Stimulation of Xenopus laevis Oocyte Maturation: INTRODUCTION

Accumulating evidence supports a role for low-density membrane (LDM) microdomains (rafts and caveolae) in cell signaling and in transmembrane and transcellular processing (for reviews, see ). Cholesterol-enriched LDM containing immunodetectable caveolin-like protein has been recovered from Xenopus laevis oocytes. Comparison of past observations in the oocyte system with more recent evidence in other cells suggests […]

Progesterone-Induced Acrosome Reaction: DISCUSSION(8)

Progesterone and zona glycoprotein (ZP3) can induce the AR but do not exert their effects through the same receptor, as far as the receptor-mediated ions fluxes are concerned. Despite the molecular dissimilarity of progesterone and ZP3, each of them can activate at least two different types of receptors responsible for Ca2+ channels—onereactingrapidly,andthusprobablyactivateddi-rectly by the inducer, […]

Progesterone-Induced Acrosome Reaction: DISCUSSION(7)

C-262- and P-BSA-conjugates have affinity only for the native, not for the denatured progesterone receptor of human and sperm samples. Therefore, we believe that identification of the progesterone receptor is not possible with Western blots of SDS-PAGE-separated sperm protein samples (although similar results were obtained on Western blots of SDS-PAGE human sperm protein samples as […]

Progesterone-Induced Acrosome Reaction: DISCUSSION(6)

These non-viable spermatozoa remained P-BSA-FITC positive, probably due to postacrosomal cytosolic staining (see Figs. 1C and 3B). Although a slightly higher proportion of P-BSA-FITC spermatozoa was determined with the flow cytometer in comparison with the fluorescence microscopy observation, the differences were smaller than 3-6%. It should be mentioned that P-BSA-FITC-stained sperm samples were analyzed as […]

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