March 8, 2024 Seminar - Mechanisms of calcium signaling and exocytosis in the adrenal medulla

Published: March 6, 2024
Arun

Arun Anatharam PhD

Abstract

Adrenal chromaffin cells serve a key physiological role as effectors of the sympathetic stress response in the periphery. In situ, chromaffin cell secretion is stimulated primarily by two neurotransmitters: acetylcholine and pituitary adenylate cyclase activating polypeptide (PACAP). This causes cells to release important stress hormones, including epinephrine, into the bloodstream. The consequences of acetylcholine activation of chromaffin cells have been studied for many decades. In contrast, the mechanisms coupling PACAP stimulation to secretion are poorly understood. Of note, PACAP is known to cause a sustained, non-desensitizing form of secretion from adrenal chromaffin cells that is critical for stress transduction in the periphery. However, the pathways that elevate Ca2+ and enable this persistent secretory response have been stubbornly difficult to resolve. In this seminar, I will discuss new findings from our group which show how PACAP causes an increase in cytosolic Ca2+ and stimulates hormone secretion from adrenal chromaffin cells. These results are not only of significance for the stress response in the periphery, but also PACAP-ergic circuit.

When: March 8, 2024

Location: North Classroom 1130

Time: 11:00 am - 12:00 pm