Glycosaminoglycan synthesis in explants derived from bleomycin-treated fibrotic hamster lungs

Glycosaminoglycan synthesis was studied in explant cultures of hamster lungs 15 and 45 days following intratracheal administration of Bleomycin. At both time points, a statistically significant increase in 35S-sulfate incorporation into glycosaminoglycans was seen in the Bleomycin-treated explants compared with that of the controls. Furthermore, the percentage of label associated with dermatan sulfate was significantly higher in the treated explants than in controls at both 15 and 45 days. Conversely, the percentage of labeled heparin and/or heparan sulfate was significantly lower for the treated explants compared to controls at these times. These results indicate that glycosaminoglycan synthesis is altered from normal in this model of interstitial lung disease. Comparison of these data with previous measurements of glycosaminoglycan synthesis in another model of interstitial lung disease, induced by N-nitroso-N-methylurethane, reveals marked similarity in the changes from normal in 35S-labeling.     

Sharp wave/ripple network oscillations and learning-associated hippocampal maps

Sharp wave/ripple (SWR, 150–250 Hz) hippocampal events have long been postulated to be involved in memory consolidation. However, more recent work has investigated SWRs that occur during active waking behaviour: findings that suggest that SWRs may also play a role in cell assembly strengthening or spatial working memory. Do such theories of SWR function apply to animal learning? This review discusses how general theories linking SWRs to memory-related function may explain circuit mechanisms related to rodent spatial learning and to the associated stabilization of new cognitive maps.