 |
Previous Article | Next Article 
Volume 16, Number 24,
Issue of December 15, 1996
pp. 8170-8180
Copyright ©1996 Society for Neuroscience
The Hypothalamic Ventromedial Nuclei Couple Activity in the
Hypothalamo-Pituitary-Adrenal Axis to the Morning Fed or Fasted
State
Received July 9, 1996; revised Sept. 13, 1996; accepted Oct. 1, 1996.
SuJean Choi,
Cydney Horsley,
Shirley Aguila, and
Mary F. Dallman
Department of Physiology, University of California San Francisco,
San Francisco, California 94143-0444
Function in the adrenocortical system is markedly altered by
availability of food. Basal activity is lowest and stress responsivity highest in the morning when nocturnal rats eat ~90% of their daily calories during the dark. After an overnight fast, basal corticotrophin and corticosteroid levels are elevated, and responsivity to stressors is decreased. Central neural sites that control these changes are
unidentified. The hypothalamic ventromedial nuclei (VMN) appear to
signal satiety; lesions result in increased food intake, obesity, and
elevated basal insulin and corticosteroids. Thus, the VMN are good
candidates for calorically mediated control of adrenocortical system
function in satiated rats. We injected colchicine into the VMN to cause
reversible inhibition of activity () and
tested the effects on basal and stimulated function in the
adrenocortical system. Colchicine-injected rats that fed ad
libitum exhibited increased basal but reduced corticotrophin and corticosterone responses to restraint in the morning compared with
controls. By contrast, after an overnight fast, control rats had
increased basal adrenocortical hormones and decreased stress responses
that did not differ from colchicine-injected rats. Colchicine was
visualized within cells in the VMN for up to 5 d using
fluorescein/colchicine, and the treatment did not cause increased
gliosis; moreover, the functional effects of the injections were
reversed within 15 d. We conclude that (1) the VMN serve to couple
activity in the adrenocortical system to energy intake and (2) discrete
colchicine injections provide a behaviorally and
neuroendocrinologically useful period of inhibition without causing
permanent functional damage.
Key words:
adrenocorticotropin;
corticosterone;
obesity;
insulin;
reversible inhibition;
colchicine
This article has been cited by other articles:

|
 |

|
 |
 
L. M. Gorton, A. M. Khan, M. Bohland, G. Sanchez-Watts, C. M. Donovan, and A. G. Watts
A Role for the Forebrain in Mediating Time-of-Day Differences in Glucocorticoid Counterregulatory Responses to Hypoglycemia in Rats
Endocrinology,
December 1, 2007;
148(12):
6026 - 6039.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. Vicentic, G. Dominguez, R. G. Hunter, K. Philpot, M. Wilson, and M. J. Kuhar
Cocaine- and Amphetamine-Regulated Transcript Peptide Levels in Blood Exhibit a Diurnal Rhythm: Regulation by Glucocorticoids
Endocrinology,
September 1, 2004;
145(9):
4119 - 4124.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. E. Bell, S. Bhatnagar, S. F. Akana, S. Choi, and M. F. Dallman
Disruption of Arcuate/Paraventricular Nucleus Connections Changes Body Energy Balance and Response to Acute Stress
J. Neurosci.,
September 1, 2000;
20(17):
6707 - 6713.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Choi, R. Sparks, M. Clay, and M. F. Dallman
Rats with Hypothalamic Obesity Are Insensitive to Central Leptin Injections
Endocrinology,
October 1, 1999;
140(10):
4426 - 4433.
[Abstract]
[Full Text]
|
 |
|

|
 |

|
 |
 
S. Choi and M. F. Dallman
Hypothalamic Obesity: Multiple Routes Mediated by Loss of Function in Medial Cell Groups
Endocrinology,
September 1, 1999;
140(9):
4081 - 4088.
[Abstract]
[Full Text]
|
 |
|

|
 |

|
 |
 
M. Eghbal-Ahmadi, S. Avishai-Eliner, C. G. Hatalski, and T. Z. Baram
Differential Regulation of the Expression of Corticotropin-Releasing Factor Receptor Type 2 (CRF2) in Hypothalamus and Amygdala of the Immature Rat by Sensory Input and Food Intake
J. Neurosci.,
May 15, 1999;
19(10):
3982 - 3991.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
K. Ogilvie and C. Rivier
The Intracerebroventricular Injection of Interleukin-1{beta} Blunts the Testosterone Response to Human Chorionic Gonadotropin: Role of Prostaglandin- and Adrenergic-Dependent Pathways
Endocrinology,
July 1, 1998;
139(7):
3088 - 3095.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Choi, L. S. Wong, C. Yamat, and M. F. Dallman
Hypothalamic Ventromedial Nuclei Amplify Circadian Rhythms: Do They Contain a Food-Entrained Endogenous Oscillator?
J. Neurosci.,
May 15, 1998;
18(10):
3843 - 3852.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. K. Elmquist, R. S. Ahima, C. F. Elias, J. S. Flier, and C. B. Saper
Leptin activates distinct projections from the dorsomedial and ventromedial hypothalamic nuclei
PNAS,
January 20, 1998;
95(2):
741 - 746.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|