Interleukin-2 stimulates the secretion of arginine vasopressin but not corticotropin-releasing hormone from rat hypothalamic cells in vitro

Objective: Adrenocorticotropic hormone (ACTH)-dependent Cushing’s syndrome is biochemically characterized by increased plasma concentrations of ACTH inducing hypersecretion of cortisol. Somatostatin is known to inhibit ACTH secretion, and in vitro data have shown the inhibition of ACTH secretion by agonists activating sst2 and sst5 receptors. The present study aimed to determine the inhibitory effect of the multireceptor ligand SOM230, compared with the sst2-preferring agonist octreotide, on corticotropin-releasing hormone (CRH)-stimulated secretion of ACTH and corticosterone in rats. Methods: Secretion of ACTH and corticosterone was induced by i.v. application of CRH (0.5 μg/kg) in rats pretreated 1 h before by i.v. application of SOM230 (1, 3, or 10 μg/kg), octreotide (10 μg/kg) or NaCl 0.9%. Results: SOM230 (3 and 10 μg/kg) inhibited CRH-induced ACTH release by 45±3% and 51±2%, respectively, and corticosterone release by 43±5% and 27±16%, respectively. 10 μg/kg of octreotide tended to be less potent at inhibiting ACTH release (34±6% inhibition) and did not alter the secretion of corticosterone. Conclusion: SOM230 has a stronger inhibitory effect on ACTH and corticosterone secretion than octreotide in rats. This difference can be explained by its higher affinity to sst1, sst3 and especially sst5 receptors compared with octreotide.

Download Full-text

Immobilization stress rapidly decreases hypothalamic corticotropin-releasing hormone secretion in vitro in the male 344/N Fischer rat

Life Sciences ◽

10.1016/0024-3205(93)90674-r ◽

1993 ◽

Vol 53 (3) ◽

pp. 233-240 ◽

Cited By ~ 15

Author(s):

Giovanni Cizza ◽

Richard Kvetnansky ◽

Maria E. Tartaglia ◽

Marc R. Blackman ◽

George P. Chrousos ◽

...

Keyword(s):

Immobilization Stress ◽

Hormone Secretion ◽

Corticotropin Releasing Hormone ◽

Releasing Hormone

Download Full-text

Consistent Reduction of ACTH responses to stimulation with CRH, Vasopressin and Hypoglycaemia in Patients with Major Depression

The British Journal of Psychiatry ◽

10.1192/bjp.155.4.468 ◽

1989 ◽

Vol 155 (4) ◽

pp. 468-478 ◽

Cited By ~ 48

Author(s):

Roger G. Kathol ◽

Richard S. Jaeckle ◽

Juan F. Lopez ◽

William H. Meller

Keyword(s):

Major Depression ◽

Hpa Axis ◽

Negative Correlation ◽

Arginine Vasopressin ◽

Corticotropin Releasing Hormone ◽

Hypothalamic Pituitary Adrenal ◽

Releasing Hormone ◽

Control Subjects ◽

Basal Cortisol ◽

Cortisol Responses

Eleven patients with major depression and 12 control subjects were administered corticotropin-releasing hormone (CRH), aqueous arginine vasopressin (AVP), and insulin hypoglycaemia (IH) to test for differences in hypothalamic–pituitary–adrenal (HPA) axis function. Patients with major depression demonstrated lower ACTH responses to CRH when compared with controls, and a trend toward such after administration of AVP. Despite lower ACTH responses in patients with depression, there were no differences in Cortisol responses to these stimuli. In the CRH and AVP tests, there was no correlation between the basal Cortisol and ACTH responses in either controls or patients, but in the IH test there was a negative correlation between these responses for both groups. The ACTH responses to CRH and AVP were positively correlated in controls and patients. Cortisol responses to all three provocative stimuli were positively correlated in both subject groups. These findings are consistent with the hypothesis that hypothalamic or supra-hypothalamic overactivity may be involved in the development of HPA-axis abnormalities in patients with depression.

Download Full-text