Role of endotoxin in the hepatic microvascular inflammatory response to ethanol.

Kupffer cells (KC) and gut-derived bacterial endotoxin have been implicated in the aetiology of alcoholic liver disease. Using in vivo microscopic methods, we have shown that ethanol ingestion in mice causes a dose dependent increase in leucocyte adhesion and endothelial cell swelling in hepatic sinusoids. Activation of KC is elicited at low doses while depression occurs at high doses and with chronic exposure.

Hydraulic conductivity of basement membrane with computed values for fiber radius and void volume ratio.

The basement membrane contributes to resistance to ultrafiltration of the capillary wall, but efforts to conduct studies of this material have been hindered by difficulty in obtaining homogenous sources and by compression from high filtration pressures. We utilized Matrigel in a conductivity chamber and showed that it reproducibly yielded a specific hydraulic conductivity of (2.247 +/- 0.

Direct observation of microtubules with the scanning tunneling microscope.

To observe surface topography of microtubules, we have applied scanning tunneling microscopy (STM), which can image metal and semiconductive surfaces with atomic resolution. Isolated microtubules fixed in 0.1% glutaraldehyde in reassembly buffer containing 0.

Reproduction in the mexican leaf frog, Pachymedusa dacnicolor. IV. Spermatogenesis: A light and ultrasonic study.

Primary spermatogonia have highly lobate nuclei and can be distinguished as pale and dark types on the basis of nuclear and cytoplasmic features. Nuclei of secondary spermatogonia are also lobate. Primary spermatocytes have spherical nuclei and display synaptinemal complexes in late zygotene-pachytene.

A study of the relationship between photoperiod and pinealocyte granulated vesicles in the golden Syrian hamster.

Previous studies in rabbits and mice have revealed distinct circadian rhythms in the number of pinealocyte granulated vesicles (PGVs) and control of their synthesis and/or secretion by sympathetic nerves. The present study demonstrates the absence of a circadian rhythm in PGV content in hamsters "functionally pinealectomized" by maintenance under long photoperiod (L/D = 14/10 h). On the other hand, a highly significant rhythm of low amplitude was noted in PGVs of hamsters placed in photoperiods (less than 12.

Effects of reserpine and p-chlorophenylalanine on the circadian rhythm of granulated vesicles in the pinealocytes of mice.

The number of granulated vesicles in mouse pinealocytes exhibit a distinct circadian rhythm which is abolished by superior cervical ganglionectomy. Since melatonin treatment markedly effects the number of pinealocytic granulated vesicles, it was suggested that a relationship may exist between norepinephrine, melatonin, and the synthesis and/or secretion of pinealocyte granulated vesicles. The present study was undertaken in an attempt to clarify this relationship.

Circadian rhythm in the number of granulated vesicles in the pinealocytes of mice. Effects of sympathectomy and melatonin treatment.

Adult, Charles River CD-1, male mice were housed in an environmental control chamber under strict conditions of controlled light (12D/12L) and temperature. The mice were sacrificed at various times throughout the twenty-four hour clock and their pineals prepared routinely for electron microscopy. The number of dense-cored or granulated vesicles present in the polar terminals of pinealocytes were quantitated in thin cross sections through pericapillary areas.