Effect of isoprostanes on sympathetic neurotransmission in the human isolated iris-ciliary body

S. Olubusayo Awe; Catherine A. Opere; Lydia C. Harris; Afam J. Uketui; Sunny E. Ohia

doi:10.1023/A:1007560025570

Effect of isoprostanes on sympathetic neurotransmission in the human isolated iris-ciliary body

S. Olubusayo Awe, Catherine A. Opere, Lydia C. Harris, Afam J. Uketui, Sunny E. Ohia

Department of Pharmacy Sciences

Research output: Contribution to journal › Article › peer-review

18 Scopus citations

Abstract

Isoprostanes (IsoP's) are prostaglandin-like compounds that are derived from free-radical catalyzed peroxidation of arachidonic acid independent of the cyclcooxygenase enzyme. In the present study, we investigated the effect of IsoP's on norepinephrine (NE) release from human isolated iris-ciliary bodies. Isolated human iris-ciliary bodies were prepared for studies of [³H]NE release using the superfusion method. Both 8-iso-prostaglandin F(2α) (F₂-IsoP) and the thromboxane (Tx) receptor agonist, U46619 enhanced field- stimulated [³H]NE release from isolated, superfused human iris-ciliary bodies without affecting basal tritium efflux. On the other hand, an equimolar concentration (10 μM) of 8-iso-prostaglandin E₂ (E₂-IsoP) inhibited evoked [³H]NE overflow. The Tx-receptor antagonist, SQ 29548 blocked the enhancements of electrically-evoked [³H]NE release induced by F₂-IsoP and U46619. However, the inhibitory responses elicited by E₂-IsoP was not antagonized by SQ 29548. We conclude that IsoP's can produce both excitatory and inhibitory effects on sympathetic neurotransmission in human isolated iris-ciliary bodies. The stimulatory effects of IsoP's on NE release may be mediated by Tx-receptors.

Original language	English (US)
Pages (from-to)	491-496
Number of pages	6
Journal	Neurochemical Research
Volume	25
Issue number	4
DOIs	https://doi.org/10.1023/A:1007560025570
State	Published - Jun 6 2000

All Science Journal Classification (ASJC) codes

Biochemistry
Cellular and Molecular Neuroscience

Access to Document

10.1023/A:1007560025570

Fingerprint Dive into the research topics of 'Effect of isoprostanes on sympathetic neurotransmission in the human isolated iris-ciliary body'. Together they form a unique fingerprint.

Cite this

@article{b948a57b871e4847a87c8dd1b611512f,

title = "Effect of isoprostanes on sympathetic neurotransmission in the human isolated iris-ciliary body",

abstract = "Isoprostanes (IsoP's) are prostaglandin-like compounds that are derived from free-radical catalyzed peroxidation of arachidonic acid independent of the cyclcooxygenase enzyme. In the present study, we investigated the effect of IsoP's on norepinephrine (NE) release from human isolated iris-ciliary bodies. Isolated human iris-ciliary bodies were prepared for studies of [3H]NE release using the superfusion method. Both 8-iso-prostaglandin F(2α) (F2-IsoP) and the thromboxane (Tx) receptor agonist, U46619 enhanced field- stimulated [3H]NE release from isolated, superfused human iris-ciliary bodies without affecting basal tritium efflux. On the other hand, an equimolar concentration (10 μM) of 8-iso-prostaglandin E2 (E2-IsoP) inhibited evoked [3H]NE overflow. The Tx-receptor antagonist, SQ 29548 blocked the enhancements of electrically-evoked [3H]NE release induced by F2-IsoP and U46619. However, the inhibitory responses elicited by E2-IsoP was not antagonized by SQ 29548. We conclude that IsoP's can produce both excitatory and inhibitory effects on sympathetic neurotransmission in human isolated iris-ciliary bodies. The stimulatory effects of IsoP's on NE release may be mediated by Tx-receptors.",

author = "Awe, {S. Olubusayo} and Opere, {Catherine A.} and Harris, {Lydia C.} and Uketui, {Afam J.} and Ohia, {Sunny E.}",

year = "2000",

month = jun,

day = "6",

doi = "10.1023/A:1007560025570",

language = "English (US)",

volume = "25",

pages = "491--496",

journal = "Neurochemical Research",

issn = "0364-3190",

publisher = "Springer New York",

number = "4",

}

TY - JOUR

T1 - Effect of isoprostanes on sympathetic neurotransmission in the human isolated iris-ciliary body

AU - Awe, S. Olubusayo

AU - Opere, Catherine A.

AU - Harris, Lydia C.

AU - Uketui, Afam J.

AU - Ohia, Sunny E.

PY - 2000/6/6

Y1 - 2000/6/6

N2 - Isoprostanes (IsoP's) are prostaglandin-like compounds that are derived from free-radical catalyzed peroxidation of arachidonic acid independent of the cyclcooxygenase enzyme. In the present study, we investigated the effect of IsoP's on norepinephrine (NE) release from human isolated iris-ciliary bodies. Isolated human iris-ciliary bodies were prepared for studies of [3H]NE release using the superfusion method. Both 8-iso-prostaglandin F(2α) (F2-IsoP) and the thromboxane (Tx) receptor agonist, U46619 enhanced field- stimulated [3H]NE release from isolated, superfused human iris-ciliary bodies without affecting basal tritium efflux. On the other hand, an equimolar concentration (10 μM) of 8-iso-prostaglandin E2 (E2-IsoP) inhibited evoked [3H]NE overflow. The Tx-receptor antagonist, SQ 29548 blocked the enhancements of electrically-evoked [3H]NE release induced by F2-IsoP and U46619. However, the inhibitory responses elicited by E2-IsoP was not antagonized by SQ 29548. We conclude that IsoP's can produce both excitatory and inhibitory effects on sympathetic neurotransmission in human isolated iris-ciliary bodies. The stimulatory effects of IsoP's on NE release may be mediated by Tx-receptors.

AB - Isoprostanes (IsoP's) are prostaglandin-like compounds that are derived from free-radical catalyzed peroxidation of arachidonic acid independent of the cyclcooxygenase enzyme. In the present study, we investigated the effect of IsoP's on norepinephrine (NE) release from human isolated iris-ciliary bodies. Isolated human iris-ciliary bodies were prepared for studies of [3H]NE release using the superfusion method. Both 8-iso-prostaglandin F(2α) (F2-IsoP) and the thromboxane (Tx) receptor agonist, U46619 enhanced field- stimulated [3H]NE release from isolated, superfused human iris-ciliary bodies without affecting basal tritium efflux. On the other hand, an equimolar concentration (10 μM) of 8-iso-prostaglandin E2 (E2-IsoP) inhibited evoked [3H]NE overflow. The Tx-receptor antagonist, SQ 29548 blocked the enhancements of electrically-evoked [3H]NE release induced by F2-IsoP and U46619. However, the inhibitory responses elicited by E2-IsoP was not antagonized by SQ 29548. We conclude that IsoP's can produce both excitatory and inhibitory effects on sympathetic neurotransmission in human isolated iris-ciliary bodies. The stimulatory effects of IsoP's on NE release may be mediated by Tx-receptors.

UR - http://www.scopus.com/inward/record.url?scp=0034027770&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0034027770&partnerID=8YFLogxK

U2 - 10.1023/A:1007560025570

DO - 10.1023/A:1007560025570

M3 - Article

C2 - 10823581

AN - SCOPUS:0034027770

VL - 25

SP - 491

EP - 496

JO - Neurochemical Research

JF - Neurochemical Research

SN - 0364-3190

IS - 4

ER -