Abstract
The effect of intra-aortic infusions of substance P (SP; 10 or 20 pmol.min-1.kg-1) on adrenal responses to acetylcholine (4.5 nmol.min-1.kg-1 ia) have been investigated in functionally hypophysectomized calves given exogenous adrenocorticotropic hormone (0.7 pmol.min-1.kg-1). At the lower dose, SP had no effect on cortisol output. In contrast, SP inhibited the output of both catecholamines and enkephalins in response to acetylcholine, without affecting the output of corticotropin-releasing factor (CRF). Increasing the dose of SP to 20 pmol.min-1.kg-1 ia significantly reduced the outputs of both cortisol and CRF (P < 0.025 and 0.01 respectively). It is concluded that SP is capable of modulating both adrenal cortical and medullary responses to acetylcholine and that the latter are more sensitive to this influence than the former.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.