Debbie Pfeiffer

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Ectoplasmic specializations of Sertoli cells are actin containing structures found at sites of attachment to spermatids and to neighboring Sertoli cells. We suspect that these cytoskeletal structures are a form of actin-associated adhesion junction. If this is true, then molecular components, such as vinculin, that characterize actin-associated adhesion(More)
Gap junction channels are essential for intercellular electrical communication in the heart. The most important cardiac gap junction proteins are connexin43 (predominantly) (Cx43), connexin40 (Cx40), and in early developmental stages connexin45. Since catecholamines play an important role in cardiac (patho)physiology, we wanted to elucidate whether(More)
Microtubules are abundant in Sertoli cells and are predominantly arranged parallel to the long axis of the cell. In addition, the centrioles occur in a perinuclear position in the basal one third of the cell. In this study we investigate the importance of the perinuclear centriole-containing centrosome as a microtubule organizing center (MTOC) in Sertoli(More)
In this paper we report the positive staining of epididymal spermatozoa and testicular cells (late spermatids and spermatozoa) with fluorescent phallotoxins. Staining is most obvious with rhodamine phalloidin, but is also detectible with NBD-phallacidin. Specific fluorescence is emitted as a linear tract along the dorsal curvature of the head and as an(More)
The aim of the present study was to clarify whether endotoxins [lipopolysaccharides (LPS)] have a toxic effect on fetal brain tissue after cerebral ischemia, while excluding their effect on the cardiovascular system. Experiments were therefore performed on hippocampal slices prepared from mature fetal guinea pigs. In particular, we studied the influence of(More)
We have studied, using electron microscopy, the basal cytoplasm of Sertoli cells in the alligator (Alligator mississippiensis) and the turtle (Pseudemys scripta). Filament bundles occur immediately adjacent to the basal plasma membrane. The diameter of these filaments is smaller than that of perinuclear intermediate filaments, but is similar to that of(More)
Ectoplasmic specializations are complex actin-containing structures found at certain sites of intercellular attachment in Sertoli cells. Current evidence indicates that these structures are a form of actin-associated adhesion junction. In the turtle (Pseudemys scripta) and rooster (Gallus domesticus) ectoplasmic specializations are known to occur adjacent(More)
The morphology and histology of the cetacean adrenal gland are poorly understood. Therefore, this study examined 32 pairs of adrenal glands from 18 pan-tropical spotted dolphins (Stenella attenuata) and 14 spinner dolphins (Stenella longirostris). In both species, the cortex was pseudolobulated and contained a typical mammalian zonation. Medullary(More)
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