We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Cold Stress and Corticotropin-Releasing Hormone Induced Changes in Messenger Ribonucleic Acid for the α[sub 1] -Subunit of the L-Type Ca[sup 2+] Channel in the Rat Anterior Pituitary and Enriched Populations of Corticotropes.
- Authors
Jiangang Xie, Gonzalo Martínez; Nagle, Gregg T.; Ritchie, Aileen K.; Collins, Thomas J.; Childs, Gwen V.
- Abstract
In response to stress, adrenocorticotropin (ACTH) is secreted from anterior pituitary corticotropes. Corticotropin-releasing hormone (CRH) is a potent stimulator of ACTH secretion. The CRH stimulation of secretion is mediated by cAMP and is largely dependent on Ca[sup 2+] influx through voltage-gated L-type Ca[sup 2+] channels. This study was designed to investigate whether the expression of L-type Ca[sup 2+] channels in the rat anterior pituitary and in corticotropes is regulated by acute stress and CRH. RNase protection assays were used to quantify α[sub 1C] mRNA of the L-type Ca[sup 2+] channel. The α[sub 1C] mRNA levels from stressed rats increased by 31% in anterior pituitaries of rats after 30 min of exposure to cold stress. Neither 60 min cold stress nor 30 min restraint stress had an effect on α[sub 1C] mRNA levels. When α[sub 1C] mRNA was detected by in situ hybridization in a population of corticotropes enriched to 90%, 0.5 nM CRH (3 h) stimulated a 36% increase in the average area of label/cell and a 10% increase in the average density of label. Our results suggest that (1) the expression of α[sub 1C] subunit mRNA of L-type Ca[sup 2+] channels is increased in the rat anterior pituitary with a stress-specific response that might reflect an increase both in thyrotropes and corticotropes (both are known to be stimulated by cold stress), and (2) the CRH-mediated increase in α[sub 1C] mRNA expression in individual rat corticotropes, in vitro, supports the hypothesis that some of the increase in vivo is due to changes in corticotropes.
- Subjects
PHYSIOLOGICAL effects of cold temperatures; CORTICOTROPIN releasing hormone; MESSENGER RNA; CALCIUM channels; NEUROENDOCRINOLOGY; IN situ hybridization; IMMUNOCYTOCHEMISTRY
- Publication
Neuroendocrinology, 1999, Vol 70, Issue 1, p10
- ISSN
0028-3835
- Publication type
Article
- DOI
10.1159/000054455