ABSTRACT
Hypoglossal motor neurons (HMNs) innervate tongue muscles and play key roles in a variety of physiological functions, including swallowing, mastication, suckling, vocalization, and respiration. Dysfunction of HMNs is associated with several diseases, such as obstructive sleep apnea (OSA) and sudden infant death syndrome. OSA is a serious breathing disorder associated with the activity of HMNs during different sleep-wake states. Identifying the neural mechanisms by which the state-dependent activities of HMNs are controlled may be helpful in providing a theoretical basis for effective therapy for OSA. However, the presynaptic partners governing the activity of HMNs remain to be elucidated. In the present study, we used a cell-type-specific retrograde tracing system based on a modified rabies virus along with a Cre/loxP gene-expression strategy to map the whole-brain monosynaptic inputs to HMNs in mice. We identified 53 nuclei targeting HMNs from six brain regions: the amygdala, hypothalamus, midbrain, pons, medulla, and cerebellum. We discovered that GABAergic neurons in the central amygdaloid nucleus, as well as calretinin neurons in the parasubthalamic nucleus, sent monosynaptic projections to HMNs. In addition, HMNs received direct inputs from several regions associated with respiration, such as the pre-Botzinger complex, parabrachial nucleus, nucleus of the solitary tract, and hypothalamus. Some regions engaged in sleep-wake regulation (the parafacial zone, parabrachial nucleus, ventral medulla, sublaterodorsal tegmental nucleus, dorsal raphe nucleus, periaqueductal gray, and hypothalamus) also provided primary inputs to HMNs. These results contribute to further elucidating the neural circuits underlying disorders caused by the dysfunction of HMNs.
ABSTRACT
Objective To study the mutability of ultra sodium pyrosulfite intake on ultrastructure changes and spermatogonium mice testis.Methods Forty male Kunming mice were used.Experimental group had been exposed to ultra sodium pyrosulfite by fed for 10 days,and sodium pyrosulfite′s contaminated dose were 1% and 1‰.Mice were killed at 11~(th) day,and ultrastructure changes were observed under transmission electron microscopy(TEM) and the tests of sister chromosome exchanges(SCE) were made.Mmutation of ultra sodium pyrosulfite on spermatogonium of mice testis was judged.Results Compared with control group,there was a significant increase of SCE ratio in spermatogonium of testis in experimental groups(P
ABSTRACT
Objective To study the effect of hydrogen peroxide on microstructure of mice kidney and discuss the toxic effect on mice kidney.Methods Thirty healthy male mice of Kunming Genus were divided into 3 groups at random:control group and two experimental groups. Running water was fed to control group for 10 days while 0.3,3 g/L hydrogen peroxide running water readily prepared was fed to the experimental groups for 10 days. On the 10th day,the kidneys were taken out,and fixed in the fixation solutions,conventionally produced and stained.Finally,they were studied under the optical microscope.Results Experimental groups:in the kidney tissue cytoplasm of proximal convoluted tubule showed hydropic degeneration and vacuolation which depend on dose of hydrogen peroxide.Conclusion Toxic effect on mice kidney can be caused by hydrogen peroxide.