Several lines of anatomic, biochemical, and pharmacological evidence suggest that the neuropeptide substance P has a direct action on cells of the anterior pituitary lobe via a specific neurokinin-1 receptor. In the present study we confirmed this association by combining Bolton-Hunter iodinated substance P-receptor autoradiography with immunocytochemistry on cultured anterior pituitary cells. ...

Many electric fish species modulate their electric organ discharges (EODs) to produce transient social signals that vary in number and structure. In Apteronotus leptorhynchus, males modulate their EOD more often than females, whereas in Apteronotus albifrons, males and females produce similar numbers of modulations. Sex differences in the number of EOD modulations in A. leptorhynchus are associ...

In order to elucidate the role of substance P in adrenal nerve activity, the effects of substance P antagonists on tonic activity of the adrenal sympathetic nerve, the response to exogenous substance P and cutaneo-adrenal nerve reflex were investigated in anesthetized rats. Substance P or its antagonist [(Arg1, D-Trp7,9, Leu11)-substance P: spantide] was injected into the subarachnoid space via...

1. It has been shown in animals that substance P as well as acetylcholine releases endothelium-derived nitric oxide and evokes vasodilatation and that ATP-induced vasodilatation is partially mediated by nitric oxide. The aim of this study was to examine whether vasodilator effects of substance P and ATP are mediated by nitric oxide in humans. 2. In healthy volunteers (n = 35), we measured forea...