Biphasic effect of GABA on rat sperm acrosome reaction: Involvement of GABAa and GABAb receptors

Jinghua Hu, X. B. He, Q. Wu, Y. C. Yan, S. S. Koide

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

The functional relationship between GABAA and GABAB receptors in regulating acrosome reaction (AR) of rat spermatozoa was demonstrated by studying the differential effects of a GABAB agonist and an antagonist on the process. AR rates were determined using the chlortetracycline staining assay. The induction of AR in rat sperm by GABA was found to be a biphasic phenomenon; i.e., AR rates increased with increasing GABA concentrations up to <5 μM and at higher concentrations of the neurotransmitter (>5 μM), there was a reduction in the AR rates. This biphasic phenomenon is apparently due to the differential interaction of the neurotransmitter with GABA receptor subtypes in a dose-dependent manner; i.e., GABAA receptors (stimulatory) are primarily activated at low concentration of GABA, while GABAB receptors (inhibitory) become activated at higher concentrations. This hypothesis is supported by the present findings that treatment with saclofen, a GABAB receptor antagonist, did not influence the AR rates effected by GABA at low concentrations; while the AR rates were maintained at the maximum level at higher concentrations of GABA, resulting in the elimination of the biphasic phenomenon. Baclofen, a GABAB receptor agonist, blocks the AR activating action of GABA at both low and high concentrations. It would appear that the induction of AR in rat sperm by GABA is regulated by the proportionality of activated GABAA and GABAB receptors acting as a yin-yang control.

Original languageEnglish (US)
Pages (from-to)369-378
Number of pages10
JournalArchives of Andrology
Volume48
Issue number5
DOIs
StatePublished - 2002
Externally publishedYes

Fingerprint

Acrosome Reaction
gamma-Aminobutyric Acid
Spermatozoa
GABA-A Receptors
Yin-Yang
Chlortetracycline
Baclofen
GABA Receptors
Neurotransmitter Agents
Staining and Labeling

Keywords

  • Baclofen
  • Capacitation
  • Chlortetracycline staining
  • Fertilization
  • Saclofen

ASJC Scopus subject areas

  • Endocrinology

Cite this

Biphasic effect of GABA on rat sperm acrosome reaction : Involvement of GABAa and GABAb receptors. / Hu, Jinghua; He, X. B.; Wu, Q.; Yan, Y. C.; Koide, S. S.

In: Archives of Andrology, Vol. 48, No. 5, 2002, p. 369-378.

Research output: Contribution to journalArticle

Hu, Jinghua ; He, X. B. ; Wu, Q. ; Yan, Y. C. ; Koide, S. S. / Biphasic effect of GABA on rat sperm acrosome reaction : Involvement of GABAa and GABAb receptors. In: Archives of Andrology. 2002 ; Vol. 48, No. 5. pp. 369-378.
@article{3677bf7c6df141459c0f2b562d86c59a,
title = "Biphasic effect of GABA on rat sperm acrosome reaction: Involvement of GABAa and GABAb receptors",
abstract = "The functional relationship between GABAA and GABAB receptors in regulating acrosome reaction (AR) of rat spermatozoa was demonstrated by studying the differential effects of a GABAB agonist and an antagonist on the process. AR rates were determined using the chlortetracycline staining assay. The induction of AR in rat sperm by GABA was found to be a biphasic phenomenon; i.e., AR rates increased with increasing GABA concentrations up to <5 μM and at higher concentrations of the neurotransmitter (>5 μM), there was a reduction in the AR rates. This biphasic phenomenon is apparently due to the differential interaction of the neurotransmitter with GABA receptor subtypes in a dose-dependent manner; i.e., GABAA receptors (stimulatory) are primarily activated at low concentration of GABA, while GABAB receptors (inhibitory) become activated at higher concentrations. This hypothesis is supported by the present findings that treatment with saclofen, a GABAB receptor antagonist, did not influence the AR rates effected by GABA at low concentrations; while the AR rates were maintained at the maximum level at higher concentrations of GABA, resulting in the elimination of the biphasic phenomenon. Baclofen, a GABAB receptor agonist, blocks the AR activating action of GABA at both low and high concentrations. It would appear that the induction of AR in rat sperm by GABA is regulated by the proportionality of activated GABAA and GABAB receptors acting as a yin-yang control.",
keywords = "Baclofen, Capacitation, Chlortetracycline staining, Fertilization, Saclofen",
author = "Jinghua Hu and He, {X. B.} and Q. Wu and Yan, {Y. C.} and Koide, {S. S.}",
year = "2002",
doi = "10.1080/01485010290099246",
language = "English (US)",
volume = "48",
pages = "369--378",
journal = "Systems Biology in Reproductive Medicine",
issn = "1939-6368",
publisher = "Informa Healthcare",
number = "5",

}

TY - JOUR

T1 - Biphasic effect of GABA on rat sperm acrosome reaction

T2 - Involvement of GABAa and GABAb receptors

AU - Hu, Jinghua

AU - He, X. B.

AU - Wu, Q.

AU - Yan, Y. C.

AU - Koide, S. S.

PY - 2002

Y1 - 2002

N2 - The functional relationship between GABAA and GABAB receptors in regulating acrosome reaction (AR) of rat spermatozoa was demonstrated by studying the differential effects of a GABAB agonist and an antagonist on the process. AR rates were determined using the chlortetracycline staining assay. The induction of AR in rat sperm by GABA was found to be a biphasic phenomenon; i.e., AR rates increased with increasing GABA concentrations up to <5 μM and at higher concentrations of the neurotransmitter (>5 μM), there was a reduction in the AR rates. This biphasic phenomenon is apparently due to the differential interaction of the neurotransmitter with GABA receptor subtypes in a dose-dependent manner; i.e., GABAA receptors (stimulatory) are primarily activated at low concentration of GABA, while GABAB receptors (inhibitory) become activated at higher concentrations. This hypothesis is supported by the present findings that treatment with saclofen, a GABAB receptor antagonist, did not influence the AR rates effected by GABA at low concentrations; while the AR rates were maintained at the maximum level at higher concentrations of GABA, resulting in the elimination of the biphasic phenomenon. Baclofen, a GABAB receptor agonist, blocks the AR activating action of GABA at both low and high concentrations. It would appear that the induction of AR in rat sperm by GABA is regulated by the proportionality of activated GABAA and GABAB receptors acting as a yin-yang control.

AB - The functional relationship between GABAA and GABAB receptors in regulating acrosome reaction (AR) of rat spermatozoa was demonstrated by studying the differential effects of a GABAB agonist and an antagonist on the process. AR rates were determined using the chlortetracycline staining assay. The induction of AR in rat sperm by GABA was found to be a biphasic phenomenon; i.e., AR rates increased with increasing GABA concentrations up to <5 μM and at higher concentrations of the neurotransmitter (>5 μM), there was a reduction in the AR rates. This biphasic phenomenon is apparently due to the differential interaction of the neurotransmitter with GABA receptor subtypes in a dose-dependent manner; i.e., GABAA receptors (stimulatory) are primarily activated at low concentration of GABA, while GABAB receptors (inhibitory) become activated at higher concentrations. This hypothesis is supported by the present findings that treatment with saclofen, a GABAB receptor antagonist, did not influence the AR rates effected by GABA at low concentrations; while the AR rates were maintained at the maximum level at higher concentrations of GABA, resulting in the elimination of the biphasic phenomenon. Baclofen, a GABAB receptor agonist, blocks the AR activating action of GABA at both low and high concentrations. It would appear that the induction of AR in rat sperm by GABA is regulated by the proportionality of activated GABAA and GABAB receptors acting as a yin-yang control.

KW - Baclofen

KW - Capacitation

KW - Chlortetracycline staining

KW - Fertilization

KW - Saclofen

UR - http://www.scopus.com/inward/record.url?scp=0036340670&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0036340670&partnerID=8YFLogxK

U2 - 10.1080/01485010290099246

DO - 10.1080/01485010290099246

M3 - Article

C2 - 12230823

AN - SCOPUS:0036340670

VL - 48

SP - 369

EP - 378

JO - Systems Biology in Reproductive Medicine

JF - Systems Biology in Reproductive Medicine

SN - 1939-6368

IS - 5

ER -