NPY in plasma and its clearance

1990 Rudehill et al., 1987). However, strong sympathetic activation is required to release enough NPY to raise systemic plasma NPY levels in man (Lundberg et al., 1985 Pernow et al., 1986a). 

The adrenals of many species co-store NPY and NA but, as indicated above, the physiological role of adrenal NPY remains unclear. Thus, like NA, plasma NPY can be used as an indicator of high sympathetic tone rather than documenting NPY concentration at its site of receptor activation. 

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