Direct effects of serotonin and ketanserin on the functional morphology of embryonic chick skin in vitro

Mesangial cells (MCs) grown without supplemental insulin (SI-MCs) express a quiescent phenotype and extracellular matrix (ECM) composition similar to MCs in vivo. In contrast, MCs routinely propagated in insulin (SI+MCs) are stimulated to proliferate, change their phenotype, and produce large amounts of collagens I and III. These effects of insulin may in part be mediated through cytoskeletal rearrangement. Differences in cytoskeletal arrangement were compared between SI-MCs and SI+MCs and 1 hr after addition of insulin (1 nM) or IGF-1 (100 nM) to SI-MCs. Cells were examined by light microscopy, electron microscopy, and immunostaining for specific cytoskeletal proteins and fibronectin. Insulin induced rapid rearrangement of stress fibers. Surface ruffling, actin aggregation, vimentin retraction, rearrangement of vinculin in focal adhesions, and fibronectin extraction were apparent. These direct effects of insulin on the SI-MC cytoskeleton occurred before insulin-induced changes in ECM composition. IGF-I induced cytoskeletal reorganization distinct from insulin. These observations demonstrate that insulin and IGF-I have unique effects on the MC cytoskeleton, which is turn may mediate secondary ligand effects on MCs.

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Direct Effects of Estradiol and Tamoxifen on Gene Expressions of Inhibin .ALPHA.- and .BETA.A-Subunits in Rat Granulosa Cells In Vitro.

Endocrine Journal ◽

10.1507/endocrj.43.621 ◽

1996 ◽

Vol 43 (6) ◽

pp. 621-628 ◽

Cited By ~ 5

Author(s):

SHINTARO TATE ◽

NOBUHIKO SUGANUMA ◽

MADOKA FURUHASHI ◽

TOMOKO ANDO ◽

YOSHIMASA ASADA ◽

...

Keyword(s):

Granulosa Cells ◽

Direct Effects ◽

Gene Expressions

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Absence of direct effects of prostaglandins on rabbit blastocysts in vitro

Prostaglandins ◽

10.1016/0090-6980(74)90048-3 ◽

1974 ◽

Vol 8 (3) ◽

pp. 253-258 ◽

Cited By ~ 3

Author(s):

G. Chaudhuri ◽

J. Harvey

Keyword(s):

Direct Effects

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Changes in Seryl-tRNA Formative in Developing Chick Muscle

Canadian Journal of Biochemistry ◽

10.1139/o74-120 ◽

1974 ◽

Vol 52 (10) ◽

pp. 838-844 ◽

Cited By ~ 3

Author(s):

Mark Nwagwu ◽

John Lianga

Keyword(s):

Muscle Protein ◽

Muscle Protein Synthesis ◽

Deae Cellulose ◽

The Other ◽

Embryonic Chick ◽

Qualitative And Quantitative ◽

Embryonic Muscle ◽

Quantitative Changes ◽

The One

As a prelude to an analysis of the dependence of muscle protein synthesis on aminoacyl tRNA's, we have investigated the rates of seryl-tRNA formation, in vitro, by aminoacylating systems isolated from 11-, 14-, and 17-day chick embryonic muscle. The results show that the combination of 14-day tRNA and 14-day aminoacyl synthetase is the most efficient in seryl-tRNA formation. We have also studied the qualitative and quantitative changes in seryl-tRNA prepared from 11-, 14-, and 17-day embryonic chick muscle by chromatography of seryl-tRNA on benzoylated DEAE-cellulose columns. The results show that, although there are no qualitative differences in the chromatographic patterns of seryl-tRNA from the different ages, there are significant quantitative differences between the patterns for 11-day and 17-day seryl-tRNA on the one hand, and the pattern for 14-day seryl-tRNA on the other.

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Acetylcholine-Cholinesterase Relationships in Embryonic Chick Lung Cultivated in vitro

Experimental Biology and Medicine ◽

10.3181/00379727-96-23597 ◽

1957 ◽

Vol 96 (3) ◽

pp. 747-750 ◽

Cited By ~ 7

Author(s):

A. Burkhalter ◽

M. Jones ◽

R. M. Featherstone

Keyword(s):

Embryonic Chick

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Control of gap junction formation in canine trachea by arachidonic acid metabolites

AJP Cell Physiology ◽

10.1152/ajpcell.1986.250.3.c495 ◽

1986 ◽

Vol 250 (3) ◽

pp. C495-C505 ◽

Cited By ~ 33

Author(s):

R. Agrawal ◽

E. E. Daniel

Keyword(s):

Arachidonic Acid ◽

Gap Junctions ◽

Gap Junction ◽

Direct Effects ◽

Leukotriene C4 ◽

Lipoxygenase Pathway ◽

Junction Formation ◽

Acid Metabolites ◽

Pg E2

This study examined whether the synthesis of the metabolites of arachidonic acid (AA) was involved in gap junction formation by 4-aminopyridine (4-AP) treatment in vitro in canine trachealis. Studies were made of the effects on gap junction formation of putative inhibitors of the cyclooxygenase and of both this and the lipoxygenase pathway of AA metabolism and the direct effects of prostaglandins (PG) E2 and I2. The number of gap junctions of similar size was increased after brief exposure to 4-AP. After indomethacin (IDM), 4-AP treatment decreased the number of gap junctions but did not affect their size. Pretreatment with 5,8,11,14-eicosatetraynoic acid or nordihydroguiaretic acid, putative inhibitors of cyclooxygenase and lipoxygenase enzymes, inhibited both the 4-AP-induced increase and decrease in the number of gap junctions. FPL 55712, a putative antagonist of leukotriene C4, did not alter either the number or the size of gap junctions when added alone or in combination with IDM. AA alone increased the number of gap junctions, but after IDM, AA decreased the number of gap junctions compared with the controls. Incubation of trachealis strips in vitro for 30 min with PGE2 increased the number of gap junctions by about threefold along with an increase in the size of the gap junctions. Similar incubation with PGI2, however, increased the number of gap junctions by approximately 60% without any change in the size. In the course of some control experiments, an interaction between carbachol and alcohol was observed such that alcohol caused an IDM-sensitive relaxation of carbachol-induced contractions, which was not observed when serotonin was the contractile agent. These results strongly suggest that PGE2 and PGI2 increase the formation of gap junctions in canine trachealis and that these prostanoids are released by 4-AP treatment. Leukotrienes may also be inhibitory in the formation of gap junctions, but FPL 55712 did not affect either the increase or the decrease in gap junctions after 4-AP.

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