Faculty Bibliography

This paper presents a series of experiments, both in patients and computer models, investigating the transition from acute to chronic hypercapnia in OSA. The data demonstrate that acute hypercapnia during periodic breathing occurs due to either reduction in magnitude of inter-event ventilation and/or reduction in inter-event ventilatory duration relative to duration of the preceding event. The transition between acute hypercapnia during sleep and chronic sustained hypercapnia during wakefulness may be determined by an interaction between respiratory control and renal handling of HCO3-.

BACKGROUND: Fibers containing galanin (GAL) enlarge and hyperinnervate cholinergic basal forebrain (CBF) nucleus basalis (NB) neurons in late-stage Alzheimer's disease (AD), yet the physiological consequences of this phenomenon are unclear. OBJECTIVE: To determine whether GAL hyperinnervation of cholinergic NB neurons modulates the expression of genes critical to cholinergic transmission [e.g. acetylcholine (ACh) metabolism and ACh receptors] in AD. METHODS: Single-cell gene expression profiling was used to compare cholinergic mRNA levels in non-GAL-hyperinnervated NB neurons in tissue autopsied from cases classified as having no cognitive impairment (NCI) or late-stage AD (AD/GAL-) and in GAL-hyperinnervated (AD/GAL+) NB neurons from the same AD subjects. RESULTS: AD/GAL+ cells displayed a significant upregulation in choline acetyltransferase (ChAT) mRNA expression compared to NCI and AD/GAL- cells. CONCLUSION: GAL fiber hyperinnervation of cholinergic NB neurons upregulates the expression of ChAT, the synthetic enzyme for ACh, suggesting that GAL regulates the cholinergic tone of CBF neurons in AD