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

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Glucoregulation and simulated diving in the harbor seal Phoca vitulina.
    Author: Robin ED, Ensinck J, Hance AJ, Newman A, Lewiston N, Cornell L, Davis RW, Theodore J.
    Journal: Am J Physiol; 1981 Nov; 241(5):R293-300. PubMed ID: 7030088.
    Abstract:
    Plasma glucose, glucagon, and insulin concentrations were measured in the harbor seal, Phoca vitulina, during a 6-min dive and a 30-min recovery period. Studies were performed in the fasting state and following intravenous glucose. During diving in the fasting state, values of plasma glucose, glucagon, and insulin are not significantly different from prediving values, presumably because of the loss of perfusion to the pancreas. In the postdiving period, plasma glucagon increases significantly. The increased glucagon levels reach a peak at 6 min into the postdiving period. By 4 min postdiving, plasma glucose values increase. The hyperglycemia appears to be at least partially related to hyperglucagonemia. Despite hyperglycemia, insulin levels do not change significantly. The net effect is to increase glucose availability, particularly for non-insulin-requiring tissues (brain). Preadministration of glucose eliminates the postdiving increase in glucagon. Plasma glucose and insulin concentrations also show no significant changes during the diving and postdiving periods. These results suggest that hormonally mediated glucose conservation serves to maintain brain glucose supplies and to restore peripheral carbohydrate stores during the postdiving period.
    [Abstract] [Full Text] [Related] [New Search]