TY - JOUR
T1 - Gap junctions formed of connexin43 are found between smooth muscle cells of human corpus cavernosum
AU - De Carvalho, A. C.C.
AU - Roy, C.
AU - Moreno, A. P.
AU - Melman, A.
AU - Hertzberg, E. L.
AU - Christ, G. J.
AU - Spray, D. C.
PY - 1993
Y1 - 1993
N2 - Despite sparse autonomic innervation, the smooth muscle cells of the corpus cavernosum relax and contract synchronously to achieve penile erection and flaccidity. As with other smooth muscle cell types, the excitation process in the corpora is presumably propagated through gap junctions to allow the diffusion of current-carrying ions and second messenger molecules from cell to cell. Using both molecular and immunocytochemical techniques, we have identified gap junctions between human corporal smooth muscle cells in situ and in culture. Northern analyses demonstrated that corporal smooth muscle cells express the gap junction protein connexin43, but not connexin26 mRNA. Immunoblots showed the presence of connexin43 isoforms, whereas connexin32 was not detected. Immunocytochemical studies in cultured cells identified prominent connexin43 immunoreactive puncta between cells, as well as within the cytoplasm. In addition, gap junction membranes both in situ and in culture were labelled in thin section by anti-connexin43 antibodies using the immunogold technique. We conclude that the presence and distribution of gap junctions in this sparsely innervated tissue may provide an important mechanism of intercellular communication among the smooth muscle cells, and thus play a major role in coordinating tissue contraction and relaxation.
AB - Despite sparse autonomic innervation, the smooth muscle cells of the corpus cavernosum relax and contract synchronously to achieve penile erection and flaccidity. As with other smooth muscle cell types, the excitation process in the corpora is presumably propagated through gap junctions to allow the diffusion of current-carrying ions and second messenger molecules from cell to cell. Using both molecular and immunocytochemical techniques, we have identified gap junctions between human corporal smooth muscle cells in situ and in culture. Northern analyses demonstrated that corporal smooth muscle cells express the gap junction protein connexin43, but not connexin26 mRNA. Immunoblots showed the presence of connexin43 isoforms, whereas connexin32 was not detected. Immunocytochemical studies in cultured cells identified prominent connexin43 immunoreactive puncta between cells, as well as within the cytoplasm. In addition, gap junction membranes both in situ and in culture were labelled in thin section by anti-connexin43 antibodies using the immunogold technique. We conclude that the presence and distribution of gap junctions in this sparsely innervated tissue may provide an important mechanism of intercellular communication among the smooth muscle cells, and thus play a major role in coordinating tissue contraction and relaxation.
KW - immunohistochemistry
KW - intercellular junctions
KW - microscopy, electron
KW - penis
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U2 - 10.1016/S0022-5347(17)36455-8
DO - 10.1016/S0022-5347(17)36455-8
M3 - Article
C2 - 8388962
AN - SCOPUS:0027153392
SN - 0022-5347
VL - 149
SP - 1568
EP - 1575
JO - Investigative Urology
JF - Investigative Urology
IS - 6
ER -