These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Arginine-vasopressin in nucleus of the tractus solitarius induces hyperglycemia and brain glucose retention.
    Author: Yarkov A, Montero S, Lemus M, Roces de Alvarez-Buylla E, Alvarez-Buylla R.
    Journal: Brain Res; 2001 Jun 01; 902(2):212-22. PubMed ID: 11384615.
    Abstract:
    Hypothalamic arginine-vasopressin (AVP) plays an important role both as a neurotransmitter and hormone in the regulation of blood glucose and feeding behavior. AVP-containing axons from the parvocellular subdivision of paraventricular nucleus of the hypothalamus terminate in the nucleus of the tractus solitarius (NTS), but the function of this projection is not known. Interestingly, the NTS also receives afferent information from the carotid body and other peripheral receptors involved in glucose homeostasis. We have previously reported that stimulation of the carotid body receptors initiates a hyperglycemic reflex and increases brain glucose retention. Here we show that direct administration of micro-doses of AVP into the NTS of anesthetized or awake rats rapidly increased the levels of blood glucose concentration and brain arterio-venous (A-V) glucose difference. This effect was not observed when the same doses of AVP were injected in the brainstem outside NTS. Arginine-vasopressin antagonist microinjections alone produced a small but significant reduction in brain A-V glucose. Pre-administered VP1-receptor antagonist [beta-mercapto-beta,beta-cyclopentamethylene-propionyl(1),O-Me-Tyr(2),Arg(8)]vasopressin blocked the effects of AVP. These results indicate that AVP acting on its receptors locally within the NTS participates in glucose homeostasis, increasing both blood glucose concentration and brain A-V glucose differences. Hypothalamic AVP may facilitate hyperglycemic responses initiated by peripheral signals processed at the level of the NTS.
    [Abstract] [Full Text] [Related] [New Search]