Recurrent Moderate Hypoglycemia Ameliorates Brain Damage and Cognitive Dysfunction Induced by Severe Hypoglycemia

(Downloading may take up to 30 seconds. If the slide opens in your browser, select File -> Save As to save it.)

Click on image to view larger version.

FIG. 4.
FIG. 4.

Antecedent recurrent hypoglycemia mitigated cognitive dysfunction induced by severe hypoglycemia. Morris water maze testing was performed 6–8 weeks following severe hypoglycemic or euglycemic clamps. A: During the cue trial, CON-SH90 rats (open circles) (n = 11) performed worse as evidenced by longer escape-path lengths than those of CON-EUG rats (open triangles) (n = 7) (aP = 0.002). Notably, rats exposed to recurrent moderate hypoglycemia before severe hypoglycemia (RH-SH90, n = 9 (closed circles) had shorter escape-path lengths than CON-SH90 rats (bP = 0.0025) and performed similarly to CON-EUG and RH-EUG rats (closed triangles) (n = 9). B: A similar pattern was observed during the place trials, where CON-SH90 rats had significantly higher escape-path lengths than CON-EUG (cP = 0.0001) and RH-SH90 (dP = 0.0006) rats. C: During the probe trial, CON-SH90 rats (diagonal hatch) had significantly fewer platform crossings than CON-EUG rats (white bar) (eP = 0.014). No significant differences were observed between CON-SH90 and RH-SH90 rats (gray horizontal hatch) or between CON-EUG and RH-EUG rats (black bar). D: RH-SH90, CON-EUG, and RH-EUG rats had a spatial bias toward the target quadrant while CON-SH90 rats did not (*P < 0.0025). E: During the probe trial, CON-SH90 rats showed an average proximity to the platform location that was significantly farther away than that of the CON-EUG rats (fP = 0.014). RH-SH90 rats swam significantly closer to the platform location than CON-SH90 rats (gP = 0.014)—similar to euglycemic controls. F: The number of episodes of seizure-like behaviors observed during severe hypoglycemia 6–8 weeks prior positively correlated with average path length during the place trials (R = 0.685; P < 0.001; n = 20).

This Article

  1. Diabetes vol. 59 no. 4 1055-1062