scholarly journals Nesfatin-1 Influences the Excitability of Gastric Distension-Responsive Neurons in the Ventromedial Hypothalamic Nucleus of Rats

2017 ◽  
pp. 335-344 ◽  
Author(s):  
H. FENG ◽  
Q. WANG ◽  
F. GUO ◽  
X. HAN ◽  
M. PANG ◽  
...  

The present study investigated the effects of nesfatin-1 on gastric distension (GD)-responsive neurons via an interaction with corticotropin-releasing factor (CRF) receptor signaling in the ventromedial hypothalamic nucleus (VMH), and the potential regulation of these effects by hippocampal projections to VMH. Extracellular single-unit discharges were recorded in VHM following administration of nesfatin-1. The projection of nerve fibers and expression of nesfatin-1 were assessed by retrograde tracing and fluoro-immunohistochemical staining, respectively. Results showed that there were GD-responsive neurons in VMH; Nesfatin-1 administration and electrical stimulation of hippocampal CA1 sub-region altered the firing rate of these neurons. These changes could be partially blocked by pretreatment with the non-selective CRF antagonist astressin-B or an antibody to NUCB2/nesfatin-1. Electrolytic lesion of CA1 hippocampus reduced the effects of nesfatin-1 on VMH GD-responsive neuronal activity. These studies suggest that nesfatin-1 plays an important role in GD-responsive neuronal activity through interactions with CRF signaling pathways in VMH. The hippocampus may participate in the modulation of nesfatin-1-mediated effects in VMH.

1996 ◽  
Vol 7 (Supplement 1) ◽  
pp. 22 ◽  
Author(s):  
R CZABAK-GARBACZ ◽  
B CYGAN ◽  
A KRASOWSKI ◽  
I I KOZLOVSKII ◽  
M MAJ

1994 ◽  
Vol 72 (1) ◽  
pp. 89-96 ◽  
Author(s):  
J. A. Thornhill ◽  
I. Halvorson

Experiments were designed to determine in the same animal whether electrical stimulation of the posterior hypothalamus and ventromedial hypothalamic nucleus could specifically evoke shivering and nonshivering (brown adipose tissue) thermogenesis, respectively, in anesthetized, normothermic rats. Urethane-anesthetized, male Long–Evans rats, kept at 37 °C, had colonic (Tc), gastrocnemius muscle (Tm), intrascapular brown adipose tissue (TIBAT), and tail (Tt) temperatures measured via thermistor probes, and electromyogram activity (differential multiunit activity from bipolar recording electrodes within gastrocnemius muscle) recorded, before and after unilateral electrical stimulation (monophasic 0.5-ms pulses of 200 μA at 50 Hz for 30 s) of the posterior hypothalamus and ventromedial hypothalamic nucleus (via stereotaxically implanted concentric stimulating electrodes). Each rat showed shivering (increased electromyogram activity) following posterior hypothalamic stimulation, which caused an immediate rise in Tm values with no change in TIBAT or Tt values. Electrical stimulation of the ventromedial hypothalamic nucleus of the same animals elicited no shivering activity, but significant increases in TIBAT values occurred with no change in Tm or Tt values. Results confirm that stimulation of the posterior and ventromedial hypothalamic nuclei in rodents specifically activates shivering and nonshivering (brown adipose tissue) effector mechanisms, respectively, to raise core temperature.Key words: posterior hypothalamus, shivering thermogenesis, ventromedial hypothalamus, intrascapular brown adipose tissue thermogenesis.


1975 ◽  
Vol 228 (6) ◽  
pp. 1787-1793 ◽  
Author(s):  
T Shimazu ◽  
S Ogasawara

Hypothalamic effects on gluconeogenesis and glycosis in rat liver were studied byelectrical stimulations of the ventromedial hypothalamic nucleus (LH) without disturbing the animal's behavior. Stimulation of VMH caused a increase in the activity of phosphoenolpyruvate carboxykinase (PEPCK), a key gluconeogenic enzyme, and marked suppression of pyruvate kinase (PK), a key glycolytic enzyme, of the liver. Stimulationof LH, on the other hand, resulted in a decrease in PEPCK activity but did not alterPK activity. The maximal responses of these enzymes to hypothalamic stimulations were obtained after intermittent stimulations for 4 h. Differential estimations of thetwo isozymes of liver PK (types L and M) were made using antibody against typeM PK. The level of type M enzyme was not altered significantly on stimulation of either VMH or LH. The content of type L enzyme greatly decreased on stimulation of VMH but was not affected by stimulation of LH. The reciprical influences of VMH and LH on hepatic carbohydrate metabolism and their relation to neural-hormonal responses are discussed.


1987 ◽  
Vol 253 (3) ◽  
pp. R418-R424 ◽  
Author(s):  
H. Yoshimatsu ◽  
Y. Oomura ◽  
T. Katafuchi ◽  
A. Niijima

Activity changes of efferent adrenal sympathetic nerves in response to bilateral manipulations of the hypothalamus, partly after intra-third cerebroventricular injection of 2-deoxy-D-glucose (2-DG) were investigated in anesthetized rats. Stimulation of the middle part of the lateral hypothalamic area (LHAm) increased adrenal nerve activity, whereas lesion caused rapid and remarkable decrease. Stimulation of the anterior part of the LHA (LHAa) tended to decrease the activity, and lesion produced either rapid decrease or late moderate increase. Stimulation of the ventromedial hypothalamic nucleus (VMH) did not affect the nerve activity, but lesion increased it gradually and then remarkably. Cerebroventricular infusion of 2-DG caused remarkable increase in activity that was suppressed by LHAm lesion. Subsequent infusion of 2-DG during the period of suppressed activity was no longer effective. The increased firing rate after 2-DG was suppressed by stimulation of the VMH, whereas lesion caused no change. These findings indicate that the central regulation of adrenal nerve activity is connected with individual hypothalamic regions and consequently depends on the degree and mode of activation of the sympathoadrenal system.


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