Translocation and association of ROCK-II with RhoA and HSP27 during contraction of rabbit colon smooth muscle cells

Nitric oxide (NO) hyperpolarizes intestinal smooth muscle cells. This study was designed to determine the mechanism whereby NO activates KCa channels of circular smooth muscle of the rabbit colon. Transmural biopsies of the rabbit colon were stained for NADPH-diaphorase. Freshly dispersed circular smooth muscle cells were studied in the whole cell configuration, as well as in on-cell and excised inside-out patch recording configurations, while KCa current and the activity of KCa channels, respectively, were monitored. NADPH-diaphorase-positive nerve fibers were found in both muscle layers. NO (1%) increased whole cell net outward current by 79% and hyperpolarized resting membrane voltage from −59 to −73 mV ( n = 8 cells, P < 0.01). In the on-cell patch recording configuration, NO (0.5% or 1%) in the bath increased NP o of KCa channels; charybdotoxin (125 nM) in the pipette solution blocked this effect. In the excised inside-out patch recording configuration, NO (1%) had no effect on NP o of KCa channels. In the on-cell patch recording configuration, methylene blue (1 μM) or cystamine (5 mM) in the bath solution decreased the effect of NO (1%) on NP o of KCa channels. NP o was increased by 8-bromo-cGMP (8-BrcGMP; 1 mM), a cGMP analog, and zaprinast (100 μM), an inhibitor of cGMP phosphodiesterase. These data suggest that NO increased whole cell outward K+current by activating KCa channels through a cGMP pathway.

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Actin filament-dependent modulation of translocated RhoA, PKC α and association with HSP27 in the particulate fraction of smooth muscle cells isolated from the rabbit colon

Gastroenterology ◽

10.1016/s0016-5085(08)81628-9 ◽

2001 ◽

Vol 120 (5) ◽

pp. A327

Author(s):

Khalil N. Bitar ◽

Mercy Pawar ◽

Peedikayil E. Thomas

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Actin Filament ◽

Muscle Cells ◽

Particulate Fraction ◽

Rabbit Colon

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Agonist-induced phosphorylation of caldesmon and association with HSP 27 is mediated by PKC, ERK and P38 MAP kinases in smooth muscle cells of the rabbit colon

Gastroenterology ◽

10.1016/s0016-5085(00)85483-9 ◽

2000 ◽

Vol 118 (4) ◽

pp. A835

Author(s):

Adenike I. Ibitayo ◽

Pinglang Wang ◽

Esli E. Gollapalli ◽

Khalil N. Bitar

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Map Kinases ◽

Muscle Cells ◽

Rabbit Colon ◽

Hsp 27

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Regional differences in signalling transduction pathways among smooth muscle cells from rabbit colon

Cellular Signalling ◽

10.1016/s0898-6568(00)00114-5 ◽

2000 ◽

Vol 12 (9-10) ◽

pp. 683-689 ◽

Cited By ~ 3

Author(s):

V Carnicelli ◽

A Di Giulio ◽

G Romano ◽

A Bozzi ◽

A Oratore ◽

...

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Regional Differences ◽

Muscle Cells ◽

Rabbit Colon ◽

Signalling Transduction

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Immunogold localization of HMB-45 antigen in pulmonary lymphangiomyomatosis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141366 ◽

1995 ◽

Vol 53 ◽

pp. 998-999

Author(s):

J.M. Minda ◽

E. Dessy ◽

G. G. Pietra

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Room Temperature ◽

Osmium Tetroxide ◽

Muscle Cells ◽

Ultrastructural Localization ◽

Reproductive Age ◽

Thin Sections ◽

Smooth Muscle Proliferation ◽

Hmb 45

Pulmonary lymphangiomyomatosis (PLAM) is a rare disease occurring exclusively in women of reproductive age. It involves the lungs, lymph nodes and lymphatic ducts. In the lungs, it is characterized by the proliferation of smooth muscle cells around lymphatics in the bronchovascular bundles, lobular septa and pleura The nature of smooth muscle proliferation in PLAM is still unclear. Recently, reactivity of the smooth muscle cells for HMB-45, a melanoma-related antigen has been reported by immunohistochemistry. The purpose of this study was the ultrastructural localization of HMB-45 immunoreactivity in these cells using gold-labeled antibodies.Lung tissue from three cases of PLAM, referred to our Institution for lung transplantation, was embedded in either Poly/Bed 812 post-fixed in 1% osmium tetroxide, or in LR White, without osmication. For the immunogold technique, thin sections were placed on Nickel grids and incubated with affinity purified, monoclonal anti-melanoma antibody HMB-45 (1:1) (Enzo Diag. Co) overnight at 4°C. After extensive washing with PBS, grids were treated with Goat-anti-mouse-IgG-Gold (5nm) (1:10) (Amersham Life Sci) for 1 hour, at room temperature.

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