Subparaventricular zone

Transplant experiments indicate that the receptors for the secreted SCN factors are located near the 3rd ventricle (LeSauter Silver 1998). The major projection of the SCN is to the subparaventricular zone (SPZ) (Watts Swanson 1987), a little understood hypothalamic region flanking the 3rd ventricle. Lesions of the SPZ disrupt circadian regulation of locomotor activity (Lu et al 2001), making the SPZ the likely location of receptors for secreted SCN locomotor factors, whether synaptic or paracrine. 

Lu J, Zhang YH, Chou TC et al 2001 Contrasting effects of ibotenate lesions of the paraventricular nucleus and subparaventricular zone on sleep-wake cycle and temperature regulation. J Neurosci 21 4864-4874... 

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