HYPOXIA INDUCED EXPRESSION OF FOS IN THE DISTAL CEREBROSPINAL FLUID CONTACTING NEURONS IN THE DORSAL RAPHE NUCLEUS OF THE RAT / 神经解剖学杂志

ABSTRACT

The effects of hypoxia on the expression of Fos was studied in the distal cerebrospinal fluid contacting neurons (CSF-CNs) in the dorsal raphe nucleus (DR) of the rat. The hypoxic models mimic 8000 m high level were established in a high-altitude decompression chamber. Injecting the tracer of CB ( chorela toxin B subunit) into the rat's lateral ventricles, we investigated the distribution of the distal CSF-CNs in the DR. The single and double immunohistochemistry staining with antibodies to Fos and CB were used to observe the expression of Fos in the distal CSF-CNs in the DR. The results showed that a large number of CB-like immunoreactive (-LI) neurons (31.16 ±3.36/per section) were located in the DR. In hypoxic experimental rats, the number of Fos-LI neurons was increased sharply (40.28 ±2.17/per section, P ＜0.05 compared to control rats), and a few CB/Fos-LI neurons (2.00 ±0.39/per section) could be observed in the DR. In control rats, several Fos-LI neurons (5.55 ±0.81/per section) and no CB/Fos-LI neuron could be observed in the DR. These results suggest that some of the distal CSF-CNs in the DR may play roles in transmitting information between brain and cerebrospinal fluid and modulating the function of brain following hypoxic stimulation.