Comparative study of the molecular and functional expression of L-type Ca2+ channels and large-conductance, Ca2+-activated K+ channels in rabbit aorta and vas deferens smooth muscle

2000 ◽  
Vol 441 (5) ◽  
pp. 611-620 ◽  
Author(s):  
Susumu Ohya ◽  
Hisao Yamamura ◽  
Katsuhiko Muraki ◽  
Minoru Watanabe ◽  
Yuji Imaizumi
Keyword(s):  
Smooth Muscle ◽  
Comparative Study ◽  
Vas Deferens ◽  
Rabbit Aorta ◽  
Functional Expression ◽  
K Channels ◽  
Ca2 Channels

scholarly journals Castration Induces Down-Regulation of A-Type K+ Channel in Rat Vas Deferens Smooth Muscle

2019 ◽  
Vol 20 (17) ◽  
pp. 4073 ◽  
Author(s):  
Susumu Ohya ◽  
Katsunori Ito ◽  
Noriyuki Hatano ◽  
Akitoshi Ohno ◽  
Katsuhiko Muraki ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Vas Deferens ◽  
Oral Treatment ◽  
Functional Expression ◽  
Rat Vas Deferens ◽  
K Channel ◽  
Α Subunit ◽  
K Channels ◽  
Expression Levels ◽  
Type K

A-type K+ channels contribute to regulating the propagation and frequency of action potentials in smooth muscle cells (SMCs). The present study (i) identified the molecular components of A-type K+ channels in rat vas deferens SMs (VDSMs) and (ii) showed the long-term, genomic effects of testosterone on their expression in VDSMs. Transcripts of the A-type K+ channel α subunit, Kv4.3L and its regulatory β subunits, KChIP3, NCS1, and DPP6-S were predominantly expressed in rat VDSMs over the other related subtypes (Kv4.2, KChIP1, KChIP2, KChIP4, and DPP10). A-type K+ current (IA) density in VDSM cells (VDSMCs) was decreased by castration without changes in IA kinetics, and decreased IA density was compensated for by an oral treatment with 17α-methyltestosterone (MET). Correspondingly, in the VDSMs of castrated rats, Kv4.3L and KChIP3 were down-regulated at both the transcript and protein expression levels. Changes in Kv4.3L and KChIP3 expression levels were compensated for by the treatment with MET. These results suggest that testosterone level changes in testosterone disorders and growth processes control the functional expression of A-type K+ channels in VDSMCs.

Characterization of receptors for angiotensin in the rat vas deferens

1979 ◽  
Vol 57 (4) ◽  
pp. 417-423 ◽  
Author(s):  
J. Magnan ◽  
D. Regoli
Keyword(s):  
Smooth Muscle ◽  
Vas Deferens ◽  
Proteolytic Enzymes ◽  
Rabbit Aorta ◽  
Rat Vas Deferens ◽  
Converting Enzyme ◽  
Response Curves ◽  
Sympathetic Nerve Stimulation ◽  
The Right

Experiments were performed in the rat vas deferens to characterize the receptor for angiotensin mediating the potentiation of the sympathetic nerve stimulation by this peptide. For this purpose we measured the order of potency of various angiotensins, the affinity of two specific and competitive antagonists, and we compared the effects of several angiotensins in tissues desensitized by angiotensin II.The potency of natural angiotensins follows the order: ATII > ATI > ATIII the relative potency of a few analogues which resist degradation by proteolytic enzymes as well as the potency of three L-Ala analogues of ATII show similar changes as those observed in other smooth muscle preparations (e.g. the rabbit aorta).Affinity of antagonists was evaluated by measuring pA2 and is higher for [Leu8]-ATII than for [des-Asp1, Leu8]-ATII. Both antagonists appear to be competitive since they displace the dose-response curves of ATII and ATIII to the right without changing the slope of the curves. Desensitization with ATII renders the tissues insensitive to ATIII and to other angiotensins without changing the response of the tissues to substance P.ATII does not modify the action of exogenous NA on nonstimulated tissues. ATI has no direct effect since its action is completely blocked in the presence of an inhibitor of the converting enzyme (SQ. 14225), while the responses of the vas deferens to ATII and substance P are unaltered.It is concluded that the receptor for ATII in the rat vas deferens is of the same type as the receptor mediating contraction of the rabbit aorta.

scholarly journals Blockade by calmodulin inhibitors of Ca2+ channels in smooth muscle from rat vas deferens

1993 ◽  
Vol 109 (1) ◽  
pp. 137-141 ◽  
Author(s):  
Ken Nakazawa ◽  
Katsuya Higo ◽  
Kazuho Abe ◽  
Yoshio Tanaka ◽  
Hiroshi Saito ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Vas Deferens ◽  
Rat Vas Deferens ◽  
Calmodulin Inhibitors ◽  
Ca2 Channels

Effects of arachidonic acid on A-type potassium currents in smooth muscle cells of the guinea pig

1997 ◽  
Vol 272 (3) ◽  
pp. C860-C869 ◽  
Author(s):  
N. Nagano ◽  
Y. Imaizumi ◽  
M. Watanabe
Keyword(s):  
Fatty Acids ◽  
Arachidonic Acid ◽  
Smooth Muscle ◽  
Guinea Pig ◽  
Smooth Muscle Cells ◽  
Vas Deferens ◽  
Muscle Cells ◽  
Atrial Myocytes ◽  
K Channels ◽  
Type K

Effects of arachidonic acid (AA) and related fatty acids on Ca2+ -independent transient (A-type) K+ current (I(A)) were examined in single myocytes of guinea pig vas deferens, ureter, and proximal colon as well as in rabbit vas deferens. The peak amplitude of I(A) was reduced by external application of AA (half-maximal inhibitory concentration = approximately 1 microM). The blocking effect was not changed significantly by indomethacin, nordihydroguaiaretic acid, guanosine 5'-O-(2-thiodiphosphate), or guanosine 5'-O-(3-thiotriphosphate). Pharmacological studies suggested that the effect of AA was not mediated by activation of protein kinases A or C or tyrosine kinase. AA (20:4) was the most potent of the four types of cis-eicosanoic acids with two to five double bonds (20:2 to 20:5) that were tested. I(A)-like current in cardiac atrial myocytes of the rabbit was not affected significantly by 30 microM AA. These results indicate that AA itself directly blocks A-type K+ channels. A relationship between stereospecific chemical structure of fatty acids and their blockade of A-type K+ channels is suggested. A-type K+ channels in smooth muscle cells can be clearly resolved from those in atrial myocytes by the responses to AA.

scholarly journals TTX-sensitive Na+ and nifedipine-sensitive Ca2+ channels in rat vas deferens smooth muscle cells

1999 ◽  
Vol 1419 (2) ◽  
pp. 343-352 ◽  
Author(s):  
Andriy E. Belevych ◽  
Aleksiy V. Zima ◽  
Irina A. Vladimirova ◽  
Hanako Hirata ◽  
Aron Jurkiewicz ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vas Deferens ◽  
Muscle Cells ◽  
Rat Vas Deferens ◽  
Ca2 Channels

The Cellular Origin in Atheromatous Lesion

1970 ◽  
Vol 28 ◽  
pp. 202-203
Author(s):  
T. M. Murad ◽  
H. A. I. Newman ◽  
K. F. Kern
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Rabbit Aorta ◽  
Mixed Population ◽  
The Other ◽  
Cellular Origin ◽  
Ultrastructural Studies ◽  
Atherosclerotic Lesions ◽  
Show Evidence ◽  
Early Lesion

The origin of lipid containing cells in atheromatous lesion has been disputed. Geer in his study on atheromatous lesions of rabbit aorta, suggested that the early lesion is composed mainly of lipid-laden macrophages and the later lesion has a mixed population of macrophages and smooth muscle cells. Parker on the other hand, was able to show evidence that the rabbit lesion is primarily composed of lipid-laden cells of smooth muscle origin. The above studies and many others were done on an intact lesion without any attempt of cellular isolation previous to their ultrastructural studies. Cell isolation procedures have been established for atherosclerotic lesions through collagenase and elastase digestion Therefore this procedure can be utilized to identify the cells involved in rabbit atheroma.

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