Does acetylcholine released within the C1 area of the rostral ventrolateral medulla (RVL) tonically maintain arterial pressure

Conference · Wed Mar 05 04:00:00 UTC 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:6936688

Arneric, S P; Giuliano, R; Ernsberger, P; Underwood, M D; Reis, D J

The RVL, which contains C1 epinephrine neurons (C1 area), plays a major role in the maintenance and reflex control of arterial pressure (AP). Muscarinic cholinergic stimulation of the C1 area is sympathoexcitatory. They sought to determine whether the C1 area of rat: (1) contains choline acetyltransferase (ChAT); (2) releases acetylcholine (ACh); and (3) has ACh receptors. ChAT was immunocytochemically localized to neurons in the C1 area. ChAT activity (pmol/mg prot./40 min; N=5) varied 10-fold over 19 regions microdissected from medulla; it was highest in the hypoglossal and vagal nuclei (203 +/- 63), lowest in the pyramidal tract (19 +/- 4) and moderate in the C1 area (96 +/- 12). Muscarinic binding sites labeled by /sup 3/H-quinuclidinyl benzylate (2 nM) and identified autoradiographically had a similar distribution. Release of /sup 3/H-ACh from (1.0 x 0.5 mm) punches of the C1 area was Ca/sup 2 +/-dependent and graded with respect to the depolarization stimulus (5-55 mM K/sup +/). Bilateral microinjection of atropine sulfate (5.0 nmol/100nl) into the C1 area of urethane anesthetized rats, but not adjacent raphen., lowered MAP (mmHg: - 38 +/- 7; N=7). They conclude that the C1 area contains muscarinic cholinergic receptors and that local neurons synthesize, store and release substantial amounts of ACh. ACh released within the C1 area may participate in the tonic maintenance of resting AP.

• Research Organization: Cornell Univ. Medical College, New York, NY
• OSTI ID: 6936688
• Report Number(s): CONF-8604222-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 45:4
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACETYLCHOLINE
AMINES
AMMONIUM COMPOUNDS
ARTERIES
AUTONOMIC NERVOUS SYSTEM AGENTS
AUTORADIOGRAPHY
BIOCHEMICAL REACTION KINETICS
BLOOD PRESSURE
BLOOD VESSELS
BODY
BRAIN
CARDIOVASCULAR SYSTEM
CENTRAL NERVOUS SYSTEM
DRUGS
ESTERS
KINETICS
LABELLED COMPOUNDS
MEMBRANE PROTEINS
NERVES
NERVOUS SYSTEM
NEUROREGULATORS
ORGANIC COMPOUNDS
ORGANS
PARASYMPATHOMIMETICS
PROTEINS
QUATERNARY COMPOUNDS
REACTION KINETICS
RECEPTORS
SECRETION
TRITIUM COMPOUNDS