+ Site Statistics
References:
54,258,434
Abstracts:
29,560,870
PMIDs:
28,072,757
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Corticotropin releasing factor but not arginine vasopressin stimulates concentration dependent increases in acth secretion from a single corticotrope implications for intracellular signals in stimulus secretion coupling



Corticotropin releasing factor but not arginine vasopressin stimulates concentration dependent increases in acth secretion from a single corticotrope implications for intracellular signals in stimulus secretion coupling



Journal of Biological Chemistry 267(12): 8325-8329



The two fundamental parameters of corticotropin (ACTH) secretion are the number of secreting corticotropes and the amount of ACTH secreted by each cell. We have measured these parameters in rat corticotropes in response to increasing concentrations of corticotropin-releasing factor (CRF) or arginine vasopressin (AVP). Increasing concentrations of AVP stimulated more corticotropes to secrete, while the amount of ACTH each cell secreted remained relatively fixed (nongraded secretory response). Conversely, increasing concentrations of CRF stimulated more ACTH secretion per cell (graded secretory response), while the number of secretory cells remained relatively constant. When viewed from the perspective of a single corticotrope, it was clear that CRF and AVP induced completely distinct specific responses. We have previously shown, and provide further evidence here, that secretory responses to CRF or AVP occur in the same cell. It is therefore apparent that a single corticotrope is able to generate either a graded, or a nongraded secretory response. We have also considered the potential intracellular changes that must direct graded or nongraded secretion. It is generally accepted that CRF stimulates activation of adenylate cyclase, whereas AVP activates phosphoinositidase in pituitary corticotropes. Our findings, and others surveyed here, suggest that the activation of adenylate cyclase results in graded secretion, while the activation of phosphoinositidase induces the nongraded secretion. Graded or nongraded secretion may therefore be linked to specific second messengers. It is hypothesized that the inositol 1,4,5-trisphosphate-mediated release of an intracellular Ca2+ store constitutes a mechanism whereby phosphoinositidase-coupled hormones set in motion the nongraded secretory response. These findings suggest novel functions for individual second messengers.

Please choose payment method:






(PDF emailed within 1 workday: $29.90)

Accession: 007165236

Download citation: RISBibTeXText

PMID: 1314823


Related references

Nitric oxide stimulates ACTH secretion and the transcription of the genes encoding for NGFI-B, corticotropin-releasing factor, corticotropin-releasing factor receptor type 1, and vasopressin in the hypothalamus of the intact rat. Journal of Neuroscience 19(17): 7640-7647, 1999

Effect of ovine corticotropin releasing factor and arginine vasopressin on ACTH and aldosterone secretion in sheep. Hormone and Metabolic Research 17(8): 428-429, 1985

Oxytocin at physiological concentrations evokes adrenocorticotropin (ACTH) release from corticotrophs by increasing intracellular free calcium mobilized mainly from intracellular stores. Oxytocin displays synergistic or additive effects on ACTH-releasing factor or arginine vasopressin-induced ACTH secretion, respectively. Endocrinology 130(4): 2183-2191, 1992

The effect of acute exercise on the secretion of corticotropin releasing factor arginine vasopressin and acth as measured in pituitary venous blood from the horse. Endocrinology 128(1): 65-72, 1991

Insulin-induced hypoglycemia stimulates corticotropin-releasing factor and arginine vasopressin secretion into hypophysial portal blood of conscious, unrestrained rams. Journal of Clinical Investigation 85(6): 1716-1721, 1990

Comparative effects of corticotropin-releasing factor, arginine vasopressin, and related neuropeptides on the secretion of ACTH and α-MSH by frog anterior pituitary cells and neurointermediate lobes in vitro. General and Comparative Endocrinology 61(3): 438-445, 1986

Blockade of alpha 2-adrenoceptors stimulates basal and stress-induced adrenocorticotropin secretion in the developing rat through a central mechanism independent from corticotropin-releasing factor and arginine vasopressin. Endocrinology 135(6): 2549-2557, 1994

Studies of the secretion of corticotropin-releasing factor and arginine vasopressin into the hypophysial-portal circulation of the conscious sheep. I. Effect of an audiovisual stimulus and insulin-induced hypoglycemia. Neuroendocrinology 49(4): 367-381, 1989

Comparative effects of corticotropin releasing factor arginine vasopressin and related neuropeptides on the secretion of acth and alpha msh by frog anterior pituitary cells and neurointermediate lobes in vitro. General & Comparative Endocrinology 61(3): 438-445, 1986

Interleukin-2 stimulates the secretion of arginine vasopressin but not corticotropin-releasing hormone from rat hypothalamic cells in vitro. Brain Research. 650(2): 323-325, 1994

Studies on the synergic effect of arginine vasopressin on acth secretion combined with human corticotropin releasing hormone. Hirosaki Medical Journal 41(1): 1-14, 1989

Corticotropin releasing factor stimulates acth secretion in nelsons syndrome. Acta Endocrinologica Supplementum 103(256): 65, 1983

Ovine corticotropin releasing factor stimulates acth release from human corticotropinoma cells in culture interaction with hydrocortisone and arginine vasopressin. Clinical Endocrinology 23(3): 295-302, 1985

Corticotropin releasing factor increases acth secretion and proopiomelanocortin messenger rna levels in anterior pituitary cells through an activation of cyclic amp dependent protein kinase. Society for Neuroscience Abstracts 11(2): 799, 1985

Central modulation of immunoreactive corticotropin-releasing factor secretion by arginine vasopressin. Endocrinology 115(4): 1639-1641, 1984