The vasoactive intestinal polypeptide (VIP) receptor was characterized on the GH3 rat pituitary tumor cell line using competitive binding studies with peptides having sequence homology with VIP. Further studies investigated receptor coupling to the adenylate cyclase complex by measurement of cAMP levels. Finally, the molecular weight of the receptor was estimated by affinity labeling techniques. Studies using 125I-VIP and unlabeled competing peptides revealed a single class of high affinity binding sites with a dissociation constant (KD) of 17 +/- 2 nM (mean +/- S.E.M.) for VIP, 275 +/- 46 nM for peptide histidine isoleucine (PHI), and 1380 +/- 800 nM for human pancreatic growth hormone releasing factor (GHRF). VIP and PHI each stimulated intracellular cAMP accumulation in a dose-dependent manner; both peptides demonstrated synergism with forskolin. In contrast, GHRF neither stimulated accumulation of cAMP nor demonstrated synergism with forskolin. VIP plus PHI (1 microM each) caused no significant increase in cAMP over either VIP or PHI alone, implying that the two peptides act through the same receptor. Covalent crosslinking of 125I-VIP to its binding site using either disuccinimidyl suberate (DSS) or ethylene glycol bis(succinimidyl succinate) (EGS) was followed by SDS-PAGE and autoradiography. The result is consistent with an Mr 47 000 VIP-binding subunit comprising or being associated with the VIP receptor of GH3 pituitary tumor cells.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/0167-0115(85)90065-5 | DOI Listing |
Cancer Lett
January 2025
Department of Endocrinology, The First Medical Center of Chinese PLA General Hospital, Beijing, China 100853. Electronic address:
This study aimed to investigate the regulation and underlying mechanism of Cathepsin K (CTSK) in bone-invasive pituitary adenomas (BIPAs). A total of 1437 patients with pituitary adenomas were included and followed up. RNA sequencing, immunohistochemistry, and qRT-PCR were used to analyze CTSK expression.
View Article and Find Full Text PDFJ Appl Lab Med
January 2025
Service of Biochemistry, Clínica Universidad de Navarra, Pamplona, Spain.
Background: In prolactinoma diagnosis, current guidelines recommend prolactin (PRL) assessment, considering values exceeding 200 ng/mL highly suggestive of prolactinoma. However, subtler hyperprolactinemia is more common, and to rule out potential prolactinomas, pituitary resonance magnetic imaging (MRI) studies are necessary. These present limitations in terms of availability, costs, and delays in diagnosis.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Cardiology and Internal Medicine, Military Institute of Medicine - National Research Institute, Warsaw, Poland.
The long-term hypercortisolemia of Cushing disease (CD) may lead to hemodynamic disorders by increasing subclinical cardiac and vascular dysfunction. The purpose of this observational cohort study was to assess the relationship between hemodynamic parameters evaluated via impedance cardiography (ICG) and echocardiographic parameters reflecting left ventricular function in 54 patients newly diagnosed with CD. The parameters assessed via ICG included stroke volume index (SI), cardiac index (CI), acceleration index (ACI), velocity index (VI), systemic vascular resistance index (SVRI), total artery compliance index (TACI).
View Article and Find Full Text PDFSci Rep
January 2025
Department of Neurosurgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, China.
Transcription factors (TFs), including steroidogenic factor-1 (SF-1), T-box transcription factor (TPIT) and pituitary transcription factor-1 (PIT-1), play a pivotal role in the cytodifferentiation of adenohypophysis. However, the impact of TFs on the growth patterns of nonfunctioning pituitary adenomas (NFPAs) remains unclear. This study aims to investigate the correlation between the expression of TFs and NFPAs growth patterns.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Otolaryngology-Head and Neck Surgery, Seoul Saint Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Background: Endoscopic endonasal transsphenoidal surgery is widely used to resect pituitary adenomas, yet its impact on olfactory function after resection of the posterosuperior nasal septum remains a concern. To optimize surgical techniques to preserve olfactory function, it is essential to understand the relationship between the extent of septal resection and olfactory outcomes.
Methods: This retrospective study analyzed 295 patients who underwent pituitary adenoma surgery.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!