Effects of forskolin on cerebral blood flow: implications for a role of adenylate cyclase

Journal Article · Sat Nov 01 04:00:00 EST 1986 · Stroke; (United States)

DOI:https://doi.org/10.1161/01.STR.17.6.1299· OSTI ID:6695973

Wysham, D G; Brotherton, A F; Heistad, D D

We have studied cerebral vascular effects of forskolin, a drug which stimulates adenylate cyclase and potentiates dilator effects of adenosine in other vascular beds. Our goals were to determine whether forskolin is a cerebral vasodilator and whether it potentiates cerebral vasodilator responses to adenosine. We measured cerebral blood flow with microspheres in anesthetized rabbits. Forskolin (10 micrograms/kg per min) increased blood flow (ml/min per 100 gm) from 39 +/- 5 (mean +/- S.E.) to 56 +/- 9 (p less than 0.05) in cerebrum, and increased flow to myocardium and kidney despite a decrease in mean arterial pressure. Forskolin did not alter cerebral oxygen consumption, which indicates that the increase in cerebral blood flow is a direct vasodilator effect and is not secondary to increased metabolism. We also examined effects of forskolin on the response to infusion of adenosine. Cerebral blood flow was measured during infusion of 1-5 microM/min adenosine into one internal carotid artery, under control conditions and during infusion of forskolin at 3 micrograms/kg per min i.v. Adenosine alone increased ipsilateral cerebral blood flow from 32 +/- 3 to 45 +/- 5 (p less than 0.05). Responses to adenosine were not augmented during infusion of forskolin. We conclude that forskolin is a direct cerebral vasodilator and forskolin does not potentiate cerebral vasodilator responses to adenosine.

• Research Organization: VA Medical Center, Iowa City, IA
• OSTI ID: 6695973
• Journal Information: Stroke; (United States), Journal Name: Stroke; (United States) Vol. 6; ISSN SJCCA
• Country of Publication: United States
• Language: English

Related Subjects

551001* -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACETYLCHOLINE
ADENOSINE
AMINES
AMMONIUM COMPOUNDS
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BIOLOGICAL EFFECTS
BLOOD FLOW
BODY
BRAIN
CARDIOVASCULAR AGENTS
CARDIOVASCULAR SYSTEM
CENTRAL NERVOUS SYSTEM
CEREBRUM
DRUGS
ESTERS
HEART
KIDNEYS
MAMMALS
MICROSPHERES
MUSCLES
MYOCARDIUM
NERVOUS SYSTEM
NEUROREGULATORS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANS
PARASYMPATHOMIMETICS
QUATERNARY COMPOUNDS
RABBITS
RIBOSIDES
VASODILATION
VASODILATORS
VERTEBRATES