Limits...
Myometrial interstitial cells and the coordination of myometrial contractility.

Hutchings G, Williams O, Cretoiu D, Ciontea SM - J. Cell. Mol. Med. (2009)

Bottom Line: The dominant cell population of the uterine wall consists of smooth muscle cells that contain the contractile apparatus responsible for the generation of contractile force.Recent interest has focused on a new population of cells located throughout the myometrium on the borders of smooth muscle bundles.Calcium imaging of live tissue slices suggests that contractile signalling starts on the borders of smooth muscle bundles where m-ICLC are located and recently the possible role of extracellular ATP signalling from m-ICLC has been studied.

View Article: PubMed Central - PubMed

Affiliation: Perinatal Research Group, 10 floor, St Luc University Hospital, Brussels, Belgium. Graham.Hutchings@uclouvain.be

ABSTRACT
A strict regulation of contractility in the uterus and fallopian tube is essential for various reproductive functions. The uterus contributes, through either increased contractility or periods of relative quiescence, to: (i) expulsion of menstrual debris, (ii) sperm transport, (iii) adequate embryo placement during implantation, (iv) enlarging its capacity during pregnancy and (v) parturition. The dominant cell population of the uterine wall consists of smooth muscle cells that contain the contractile apparatus responsible for the generation of contractile force. Recent interest has focused on a new population of cells located throughout the myometrium on the borders of smooth muscle bundles. These cells are similar to interstitial cells of Cajal (ICC) in the gut that are responsible for the generation of electrical slow waves that control peristalsis. A precise role for myometrial Cajal-like interstitial cells (m-ICLC) has not been identified. m-ICLC express the c-kit receptor, involved in creating and maintaining the ICC phenotype in the gastrointestinal tract. However, both acute and prolonged inhibition of this receptor with the c-kit antagonist imatinib mesylate does not appear to affect the spontaneous contractility of myometrium. Calcium imaging of live tissue slices suggests that contractile signalling starts on the borders of smooth muscle bundles where m-ICLC are located and recently the possible role of extracellular ATP signalling from m-ICLC has been studied. This manuscript reviews the evidence regarding tissue-level signalling in the myometrium with a particular emphasis on the anatomical and possible functional aspects of m-ICLC as new elements of the contractile mechanisms in the uterus.

Show MeSH

Related in: MedlinePlus

Vital staining methods (efficient in pointing out the very long processes) performed on m-ICLC in culture. Primary confluent cultures (day 8) from pregnant human myometrium. (A) Representative m-ICLC with high affinity for methylene blue. (B) m-ICLC stained with Janus green B, a marker for mitochondria in living cells. Note the positive mitchondria in m-ICLC dilations (arrows) original magnification 40×. Modified from Ref. [8], with permission from FCMM.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4496132&req=5

fig03: Vital staining methods (efficient in pointing out the very long processes) performed on m-ICLC in culture. Primary confluent cultures (day 8) from pregnant human myometrium. (A) Representative m-ICLC with high affinity for methylene blue. (B) m-ICLC stained with Janus green B, a marker for mitochondria in living cells. Note the positive mitchondria in m-ICLC dilations (arrows) original magnification 40×. Modified from Ref. [8], with permission from FCMM.

Mentions: In the following year, another group published evidence regarding myometrial ICs which they termed m-ICLC, using a variety of immunohistochemical techniques, electron microscopy and electrophysiology [8]. First of all, they searched for m-ICLC in human myometrial tissue and cell cultures using classical staining methods used by Cajal himself when he described the cells bearing his name (Figs. 1–3A). In vitro, myometrial ICs possessed very long cytoplasmic processes which were found by staining with Janus green B to contain numerous mitochondria (Figs 3B and 4A). These cells represented approximately 7% of the total cell number when counting these cells on semi-thin sections stained with toluidin blue, considered by the authors as relevant for preliminary identification of m-ICLC (Fig. 4B). This technique is easy to perform and permits the general characterization of myometrial ICs. Ultrastructurally, two to three characteristic processes were observed and these prolongations were very long and thin (60 and <0.5 μm, respectively) (Fig. 5). The cells expressed c-kit when examined by immunofluorescence (Fig. 6) and they connected with each other and with smooth muscle cells by gap junctions. Based on ultrastructural features, a set of criteria was assembled that allowed the differentiation of m-ICLC from fibroblasts:


Myometrial interstitial cells and the coordination of myometrial contractility.

Hutchings G, Williams O, Cretoiu D, Ciontea SM - J. Cell. Mol. Med. (2009)

Vital staining methods (efficient in pointing out the very long processes) performed on m-ICLC in culture. Primary confluent cultures (day 8) from pregnant human myometrium. (A) Representative m-ICLC with high affinity for methylene blue. (B) m-ICLC stained with Janus green B, a marker for mitochondria in living cells. Note the positive mitchondria in m-ICLC dilations (arrows) original magnification 40×. Modified from Ref. [8], with permission from FCMM.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4496132&req=5

fig03: Vital staining methods (efficient in pointing out the very long processes) performed on m-ICLC in culture. Primary confluent cultures (day 8) from pregnant human myometrium. (A) Representative m-ICLC with high affinity for methylene blue. (B) m-ICLC stained with Janus green B, a marker for mitochondria in living cells. Note the positive mitchondria in m-ICLC dilations (arrows) original magnification 40×. Modified from Ref. [8], with permission from FCMM.
Mentions: In the following year, another group published evidence regarding myometrial ICs which they termed m-ICLC, using a variety of immunohistochemical techniques, electron microscopy and electrophysiology [8]. First of all, they searched for m-ICLC in human myometrial tissue and cell cultures using classical staining methods used by Cajal himself when he described the cells bearing his name (Figs. 1–3A). In vitro, myometrial ICs possessed very long cytoplasmic processes which were found by staining with Janus green B to contain numerous mitochondria (Figs 3B and 4A). These cells represented approximately 7% of the total cell number when counting these cells on semi-thin sections stained with toluidin blue, considered by the authors as relevant for preliminary identification of m-ICLC (Fig. 4B). This technique is easy to perform and permits the general characterization of myometrial ICs. Ultrastructurally, two to three characteristic processes were observed and these prolongations were very long and thin (60 and <0.5 μm, respectively) (Fig. 5). The cells expressed c-kit when examined by immunofluorescence (Fig. 6) and they connected with each other and with smooth muscle cells by gap junctions. Based on ultrastructural features, a set of criteria was assembled that allowed the differentiation of m-ICLC from fibroblasts:

Bottom Line: The dominant cell population of the uterine wall consists of smooth muscle cells that contain the contractile apparatus responsible for the generation of contractile force.Recent interest has focused on a new population of cells located throughout the myometrium on the borders of smooth muscle bundles.Calcium imaging of live tissue slices suggests that contractile signalling starts on the borders of smooth muscle bundles where m-ICLC are located and recently the possible role of extracellular ATP signalling from m-ICLC has been studied.

View Article: PubMed Central - PubMed

Affiliation: Perinatal Research Group, 10 floor, St Luc University Hospital, Brussels, Belgium. Graham.Hutchings@uclouvain.be

ABSTRACT
A strict regulation of contractility in the uterus and fallopian tube is essential for various reproductive functions. The uterus contributes, through either increased contractility or periods of relative quiescence, to: (i) expulsion of menstrual debris, (ii) sperm transport, (iii) adequate embryo placement during implantation, (iv) enlarging its capacity during pregnancy and (v) parturition. The dominant cell population of the uterine wall consists of smooth muscle cells that contain the contractile apparatus responsible for the generation of contractile force. Recent interest has focused on a new population of cells located throughout the myometrium on the borders of smooth muscle bundles. These cells are similar to interstitial cells of Cajal (ICC) in the gut that are responsible for the generation of electrical slow waves that control peristalsis. A precise role for myometrial Cajal-like interstitial cells (m-ICLC) has not been identified. m-ICLC express the c-kit receptor, involved in creating and maintaining the ICC phenotype in the gastrointestinal tract. However, both acute and prolonged inhibition of this receptor with the c-kit antagonist imatinib mesylate does not appear to affect the spontaneous contractility of myometrium. Calcium imaging of live tissue slices suggests that contractile signalling starts on the borders of smooth muscle bundles where m-ICLC are located and recently the possible role of extracellular ATP signalling from m-ICLC has been studied. This manuscript reviews the evidence regarding tissue-level signalling in the myometrium with a particular emphasis on the anatomical and possible functional aspects of m-ICLC as new elements of the contractile mechanisms in the uterus.

Show MeSH
Related in: MedlinePlus