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Title: Blastocoel expansion in the preimplantation mouse embryo

Abstract

Since cAMP can regulate fluid transport in many types of epithelia, the mechanism of fluid transport and the role of cAMP in the mouse blastocyst were examined. Results described here indicate an increase in the ability of mouse embryos to elevate cAMP levels in response to activators of adenylate cyclase, which is the enzyme that synthesizes cAMP, during the transition from morula to blastocyst. In addition, a positive correlation is observed between the increase in activatable adenylate cyclase and the presence of a blastocoel. Moreover, elevating intracellular cAMP in nascent cavitating embryos stimulates the rate of fluid transport in the blastocoel. Accumulation of fluid in the blastocoel is a function of the tight permeability seal around the embryo and the vectorial flow of ions into the blastocoel. Results reported here indicate that extracellular Na{sup +} and Cl{sup {minus}} are required for expansion of the blastocoel in nascent cavitating blastocysts. Sodium uptake into the embryo is carrier-mediated and probably occurs through multiple routes which include the Na{sup +}-channel and the Na{sup +}/H{sup +} exchanger. Chloride uptake is non-carrier mediated and may occur by a paracellular route. In addition, cAMP, which stimulates blastocoel expansion, also stimulates uptake of {sup 22}Na{sup +}. Thismore » effect may be mediated by a cAMP-dependent protein kinase, since inhibition of this enzyme inhibits both the cAMP-stimulated rate of blastocoel expansion and {sup 22}Na{sup +} uptake.« less

Authors:
Publication Date:
Research Org.:
Pennsylvania Univ., Philadelphia, PA (USA)
OSTI Identifier:
6159576
Resource Type:
Miscellaneous
Resource Relation:
Other Information: Thesis (Ph. D.)
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; AMP; BIOLOGICAL FUNCTIONS; CYCLASES; ENZYME ACTIVITY; MICE; ONTOGENESIS; SODIUM COMPOUNDS; MEMBRANE TRANSPORT; BODY FLUIDS; CHLORINE COMPOUNDS; EMBRYONIC CELLS; EMBRYOS; IMPLANTS; ION EXCHANGE; SODIUM 22; TRACER TECHNIQUES; ALKALI METAL COMPOUNDS; ALKALI METAL ISOTOPES; ANIMAL CELLS; ANIMALS; BETA DECAY RADIOISOTOPES; BETA-PLUS DECAY RADIOISOTOPES; BIOLOGICAL MATERIALS; ENZYMES; FUNCTIONS; HALOGEN COMPOUNDS; ISOMERIC TRANSITION ISOTOPES; ISOTOPE APPLICATIONS; ISOTOPES; LIGHT NUCLEI; LYASES; MAMMALS; MATERIALS; NUCLEI; NUCLEOTIDES; ODD-ODD NUCLEI; ORGANIC COMPOUNDS; RADIOISOTOPES; RODENTS; SODIUM ISOTOPES; VERTEBRATES; YEARS LIVING RADIOISOTOPES; 550201* - Biochemistry- Tracer Techniques

Citation Formats

Manejwala, F.M. Blastocoel expansion in the preimplantation mouse embryo. United States: N. p., 1989. Web.
Manejwala, F.M. Blastocoel expansion in the preimplantation mouse embryo. United States.
Manejwala, F.M. Sun . "Blastocoel expansion in the preimplantation mouse embryo". United States. doi:.
@article{osti_6159576,
title = {Blastocoel expansion in the preimplantation mouse embryo},
author = {Manejwala, F.M.},
abstractNote = {Since cAMP can regulate fluid transport in many types of epithelia, the mechanism of fluid transport and the role of cAMP in the mouse blastocyst were examined. Results described here indicate an increase in the ability of mouse embryos to elevate cAMP levels in response to activators of adenylate cyclase, which is the enzyme that synthesizes cAMP, during the transition from morula to blastocyst. In addition, a positive correlation is observed between the increase in activatable adenylate cyclase and the presence of a blastocoel. Moreover, elevating intracellular cAMP in nascent cavitating embryos stimulates the rate of fluid transport in the blastocoel. Accumulation of fluid in the blastocoel is a function of the tight permeability seal around the embryo and the vectorial flow of ions into the blastocoel. Results reported here indicate that extracellular Na{sup +} and Cl{sup {minus}} are required for expansion of the blastocoel in nascent cavitating blastocysts. Sodium uptake into the embryo is carrier-mediated and probably occurs through multiple routes which include the Na{sup +}-channel and the Na{sup +}/H{sup +} exchanger. Chloride uptake is non-carrier mediated and may occur by a paracellular route. In addition, cAMP, which stimulates blastocoel expansion, also stimulates uptake of {sup 22}Na{sup +}. This effect may be mediated by a cAMP-dependent protein kinase, since inhibition of this enzyme inhibits both the cAMP-stimulated rate of blastocoel expansion and {sup 22}Na{sup +} uptake.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 1989},
month = {Sun Jan 01 00:00:00 EST 1989}
}

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