Chemically evoked release of an angiotensin-like peptide from fetal rat brain cells in culture

• Published in: The American journal of physiology Vol. 251; no. 1 Pt 1; p. C17
• Main Authors: Meyer, J M, Weyhenmeyer, J A
• Format: Journal Article
• Language: English
• Published: United States 01.07.1986
• Subjects: Angiotensin II - metabolism; Angiotensin II - physiology; Animals; Brain - metabolism; Calcium Chloride - pharmacology; Cells, Cultured; Chromatography, High Pressure Liquid; Female; Fetus; Neurons - metabolism; Potassium Chloride - pharmacology; Radioimmunoassay; Rats; Rats, Inbred Strains; Renin-Angiotensin System; Stimulation, Chemical
• ISSN: 0002-9513
• DOI: 10.1152/ajpcell.1986.251.1.c17

Recent evidence has demonstrated that dissociated fetal rat brain cells in culture synthesize an angiotensin II (ANG II)-like peptide that shares common properties with authentic ANG II, suggesting that brain has a complete renin angiotensin system that is independent of peripheral substrates. Although ANG II has been postulated to function as a neurotransmitter/neuromodulator, the release of ANG II from presynaptic nerve terminals has not been established. To investigate the mechanism of ANG II release, brain cells from 20-day gestational age Sprague-Dawley rats were dissociated by mild trypsinization and grown in culture. The cells were maintained in serum-free medium for 5 days prior to experimental analysis. Cultured brain cells were challenged with 59 mM KCl in the presence or absence of 5 mM CaCl2, and the incubation medium was measured for the release of ANG II by radioimmunoassay and high-performance liquid chromatography. The data demonstrate that K+ stimulation results in a rapid and time-dependent release of ANG II-like peptide that is Ca2+ dependent. We have concluded that these findings are consistent with those for other neurotransmitter/neurohormone systems and therefore provide further support for the role of ANG II as a chemical transmitter in the brain.