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Modulation of Sleep Homeostasis by Corticotropin Releasing Hormone in REM Sleep-Deprived Rats.

Machado RB, Tufik S, Suchecki D - Int J Endocrinol (2010)

Bottom Line: Throughout 96 hours of sleep deprivation, separate groups of rats were treated i.c.v. with vehicle, CRH or with alphahelical CRH(9-41), a CRH receptor blocker, twice/day, at 07:00 h and 19:00 h.These changes suggest that activation of the CRH system impact negatively on the homeostatic sleep response to prolonged forced waking.These results indicate that indeed, activation of the HPA axis-at least at the hypothalamic level-is capable to reduce the sleep rebound induced by sleep deprivation.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Psicobiologia, Universidade Federal de São Paulo, 04024-002 São Paulo, Brazil.

ABSTRACT
Studies have shown that sleep recovery following different protocols of forced waking varies according to the level of stress inherent to each method. Sleep deprivation activates the hypothalamic-pituitary-adrenal axis and increased corticotropin-releasing hormone (CRH) impairs sleep. The purpose of the present study was to evaluate how manipulations of the CRH system during the sleep deprivation period interferes with subsequent sleep rebound. Throughout 96 hours of sleep deprivation, separate groups of rats were treated i.c.v. with vehicle, CRH or with alphahelical CRH(9-41), a CRH receptor blocker, twice/day, at 07:00 h and 19:00 h. Both treatments impaired sleep homeostasis, especially in regards to length of rapid eye movement sleep (REM) and theta/delta ratio and induced a later decrease in NREM and REM sleep and increased waking bouts. These changes suggest that activation of the CRH system impact negatively on the homeostatic sleep response to prolonged forced waking. These results indicate that indeed, activation of the HPA axis-at least at the hypothalamic level-is capable to reduce the sleep rebound induced by sleep deprivation.

No MeSH data available.


Related in: MedlinePlus

Spectral Power During Total NREM on the 2nd (a) and 3rd (b) Recovery Dark Phases. Results are expressed as percentage of ACSF-treated group, obtained from the mean power of each spectra band. ACSF, artificial cerebrospinal fluid; CRH, corticotrophin-releasing hormone; αhCRH, alpha helical CRH9−41. Grey line above graphics indicates differences of αhCRH from ACSF and black ones, the difference between the CRH and αhCRH treatments. Student's t tests, P ≤ .05.
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Related In: Results  -  Collection


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fig5: Spectral Power During Total NREM on the 2nd (a) and 3rd (b) Recovery Dark Phases. Results are expressed as percentage of ACSF-treated group, obtained from the mean power of each spectra band. ACSF, artificial cerebrospinal fluid; CRH, corticotrophin-releasing hormone; αhCRH, alpha helical CRH9−41. Grey line above graphics indicates differences of αhCRH from ACSF and black ones, the difference between the CRH and αhCRH treatments. Student's t tests, P ≤ .05.

Mentions: No changes were found.


Modulation of Sleep Homeostasis by Corticotropin Releasing Hormone in REM Sleep-Deprived Rats.

Machado RB, Tufik S, Suchecki D - Int J Endocrinol (2010)

Spectral Power During Total NREM on the 2nd (a) and 3rd (b) Recovery Dark Phases. Results are expressed as percentage of ACSF-treated group, obtained from the mean power of each spectra band. ACSF, artificial cerebrospinal fluid; CRH, corticotrophin-releasing hormone; αhCRH, alpha helical CRH9−41. Grey line above graphics indicates differences of αhCRH from ACSF and black ones, the difference between the CRH and αhCRH treatments. Student's t tests, P ≤ .05.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2902042&req=5

fig5: Spectral Power During Total NREM on the 2nd (a) and 3rd (b) Recovery Dark Phases. Results are expressed as percentage of ACSF-treated group, obtained from the mean power of each spectra band. ACSF, artificial cerebrospinal fluid; CRH, corticotrophin-releasing hormone; αhCRH, alpha helical CRH9−41. Grey line above graphics indicates differences of αhCRH from ACSF and black ones, the difference between the CRH and αhCRH treatments. Student's t tests, P ≤ .05.
Mentions: No changes were found.

Bottom Line: Throughout 96 hours of sleep deprivation, separate groups of rats were treated i.c.v. with vehicle, CRH or with alphahelical CRH(9-41), a CRH receptor blocker, twice/day, at 07:00 h and 19:00 h.These changes suggest that activation of the CRH system impact negatively on the homeostatic sleep response to prolonged forced waking.These results indicate that indeed, activation of the HPA axis-at least at the hypothalamic level-is capable to reduce the sleep rebound induced by sleep deprivation.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Psicobiologia, Universidade Federal de São Paulo, 04024-002 São Paulo, Brazil.

ABSTRACT
Studies have shown that sleep recovery following different protocols of forced waking varies according to the level of stress inherent to each method. Sleep deprivation activates the hypothalamic-pituitary-adrenal axis and increased corticotropin-releasing hormone (CRH) impairs sleep. The purpose of the present study was to evaluate how manipulations of the CRH system during the sleep deprivation period interferes with subsequent sleep rebound. Throughout 96 hours of sleep deprivation, separate groups of rats were treated i.c.v. with vehicle, CRH or with alphahelical CRH(9-41), a CRH receptor blocker, twice/day, at 07:00 h and 19:00 h. Both treatments impaired sleep homeostasis, especially in regards to length of rapid eye movement sleep (REM) and theta/delta ratio and induced a later decrease in NREM and REM sleep and increased waking bouts. These changes suggest that activation of the CRH system impact negatively on the homeostatic sleep response to prolonged forced waking. These results indicate that indeed, activation of the HPA axis-at least at the hypothalamic level-is capable to reduce the sleep rebound induced by sleep deprivation.

No MeSH data available.


Related in: MedlinePlus