Loading…
Possible reasons for the variability of the inotropic insulin effect in papillary muscles of ground squirrel myocardium
The effects of insulin (0.1–50 nM) on isometric twitch force (0.1 to 1.0 Hz; 30 ± 1°C; 1.8 mM Ca 2+ ) were studied in right ventricular papillary muscles from active ground squirrels of different seasons (summer, n = 14; autumn, n = 16 and winter interbout, n = 16) in control conditions and after on...
Saved in:
Published in: | Biophysics (Oxford) 2012-11, Vol.57 (6), p.796-803 |
---|---|
Main Authors: | , , , , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
cited_by | |
---|---|
cites | cdi_FETCH-LOGICAL-c1833-9da144f482a5d350758f65cc69a7b1e0a16bba9aa3c19d9c871f3f112ec87c363 |
container_end_page | 803 |
container_issue | 6 |
container_start_page | 796 |
container_title | Biophysics (Oxford) |
container_volume | 57 |
creator | Nakipova, O. V. Chumaeva, N. A. Andreeva, L. A. Anufriev, A. I. Kukushkin, N. I. |
description | The effects of insulin (0.1–50 nM) on isometric twitch force (0.1 to 1.0 Hz; 30 ± 1°C; 1.8 mM Ca
2+
) were studied in right ventricular papillary muscles from active ground squirrels of different seasons (summer,
n
= 14; autumn,
n
= 16 and winter interbout,
n
= 16) in control conditions and after one-hour pretreatment of PM with 2 μM nifedipine (an L-type Ca
2+
-channel inhibitor) and 1.0 mM orthovanadate (a tyrosine phosphatase inhibitor). In active animals of different seasonal periods insulin causes both positive and negative inotropic effects. At low frequencies (0.1–0.5 Hz), insulin of low concentrations (0.1–1.0 nM) induces a transient (within the first 20 min after application) positive effect (about 15–25%). Application of high hormone concentration (10 nM) in a low range of stimulation frequencies causes a biphasic effect (a small initial positive inotropic effect followed by a marked negative one). At frequencies above 0.5-Hz stimulation, insulin of 10 nM concentration causes presumably a negative inotropic effect. It was proposed that ICaL is possibly involved in the insulin-induced negative inotropy in ground squirrels hearts. Alteration of protein phosphorylation in tyrosine residues is known to be a major link in the mechanism of insulin action. We performed a study on sodium orthovanadate action (a known inhibitor of tyrosine phosphatase) on the inotropic insulin effect. In the group of summer animals the pretreatment of papillary muscles with sodium orthovanadate (100 μM) does not change the negative inotropic effect of insulin in a low range of stimulation frequencies but almost completely removes this effect at stimulation frequencies above 0.3 Hz (
n
= 4). Nifedipine (1–1.5 h pretreatment), a blocker of L-type calcium channel, reduces the inhibitory effect of insulin in autumn and winter animals, and on the contrary intensifies it in summer animals. This fact indicates that different mechanisms must be involved in insulin actions in animals of summer and winter periods. The main findings of the present study are that insulin induces positive, negative or no inotropic effects in papillary muscles of ground squirrels myocardium. The character of the effects of insulin depends on the physiological state of animals; time and concentrations of the hormone applied; affected by conditions that alter cellular Ca
2+
loading and the ratio of protein-tyrosine kinases/phosphatases activity. |
doi_str_mv | 10.1134/S0006350912060103 |
format | article |
fullrecord | <record><control><sourceid>proquest_cross</sourceid><recordid>TN_cdi_proquest_journals_1312160398</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><sourcerecordid>2900477731</sourcerecordid><originalsourceid>FETCH-LOGICAL-c1833-9da144f482a5d350758f65cc69a7b1e0a16bba9aa3c19d9c871f3f112ec87c363</originalsourceid><addsrcrecordid>eNp1UE1LxDAQDaLguvoDvAU8VzNNk22PsvgFgoJ6LmmarFmyTXfSKvvvTV0Pgniar_fezDxCzoFdAvDi6oUxJrlgFeRMMmD8gMxACJFJKYpDMpvG2TQ_JicxrhmDghViRj6fQ4yu8YaiUTF0kdqAdHg39EOhU43zbtjRYL9brgsDht7plMXRu44aa40eUkl71TvvFe7oZozamziRVhjGrqVxOzpE4-lmF7TC1o2bU3JklY_m7CfOydvtzevyPnt8untYXj9mGkrOs6pVUBS2KHMl2nT-QpRWCq1lpRYNGKZANo2qlOIaqrbS5QIstwC5Sanmks_JxV63x7AdTRzqdRixSytr4JCDZLwqEwr2KI3JDjS27tFt0jM1sHryt_7jb-Lke05M2G5l8Jfyv6QvKld-Tg</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>1312160398</pqid></control><display><type>article</type><title>Possible reasons for the variability of the inotropic insulin effect in papillary muscles of ground squirrel myocardium</title><source>Springer Nature</source><creator>Nakipova, O. V. ; Chumaeva, N. A. ; Andreeva, L. A. ; Anufriev, A. I. ; Kukushkin, N. I.</creator><creatorcontrib>Nakipova, O. V. ; Chumaeva, N. A. ; Andreeva, L. A. ; Anufriev, A. I. ; Kukushkin, N. I.</creatorcontrib><description>The effects of insulin (0.1–50 nM) on isometric twitch force (0.1 to 1.0 Hz; 30 ± 1°C; 1.8 mM Ca
2+
) were studied in right ventricular papillary muscles from active ground squirrels of different seasons (summer,
n
= 14; autumn,
n
= 16 and winter interbout,
n
= 16) in control conditions and after one-hour pretreatment of PM with 2 μM nifedipine (an L-type Ca
2+
-channel inhibitor) and 1.0 mM orthovanadate (a tyrosine phosphatase inhibitor). In active animals of different seasonal periods insulin causes both positive and negative inotropic effects. At low frequencies (0.1–0.5 Hz), insulin of low concentrations (0.1–1.0 nM) induces a transient (within the first 20 min after application) positive effect (about 15–25%). Application of high hormone concentration (10 nM) in a low range of stimulation frequencies causes a biphasic effect (a small initial positive inotropic effect followed by a marked negative one). At frequencies above 0.5-Hz stimulation, insulin of 10 nM concentration causes presumably a negative inotropic effect. It was proposed that ICaL is possibly involved in the insulin-induced negative inotropy in ground squirrels hearts. Alteration of protein phosphorylation in tyrosine residues is known to be a major link in the mechanism of insulin action. We performed a study on sodium orthovanadate action (a known inhibitor of tyrosine phosphatase) on the inotropic insulin effect. In the group of summer animals the pretreatment of papillary muscles with sodium orthovanadate (100 μM) does not change the negative inotropic effect of insulin in a low range of stimulation frequencies but almost completely removes this effect at stimulation frequencies above 0.3 Hz (
n
= 4). Nifedipine (1–1.5 h pretreatment), a blocker of L-type calcium channel, reduces the inhibitory effect of insulin in autumn and winter animals, and on the contrary intensifies it in summer animals. This fact indicates that different mechanisms must be involved in insulin actions in animals of summer and winter periods. The main findings of the present study are that insulin induces positive, negative or no inotropic effects in papillary muscles of ground squirrels myocardium. The character of the effects of insulin depends on the physiological state of animals; time and concentrations of the hormone applied; affected by conditions that alter cellular Ca
2+
loading and the ratio of protein-tyrosine kinases/phosphatases activity.</description><identifier>ISSN: 0006-3509</identifier><identifier>EISSN: 1555-6654</identifier><identifier>DOI: 10.1134/S0006350912060103</identifier><language>eng</language><publisher>Dordrecht: SP MAIK Nauka/Interperiodica</publisher><subject>Animal populations ; Biological and Medical Physics ; Biophysics ; Complex Systems Biophysics ; Heart ; Insulin ; Physics ; Physics and Astronomy ; Rodents</subject><ispartof>Biophysics (Oxford), 2012-11, Vol.57 (6), p.796-803</ispartof><rights>Pleiades Publishing, Ltd. 2012</rights><woscitedreferencessubscribed>false</woscitedreferencessubscribed><cites>FETCH-LOGICAL-c1833-9da144f482a5d350758f65cc69a7b1e0a16bba9aa3c19d9c871f3f112ec87c363</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><link.rule.ids>314,780,784,27924,27925</link.rule.ids></links><search><creatorcontrib>Nakipova, O. V.</creatorcontrib><creatorcontrib>Chumaeva, N. A.</creatorcontrib><creatorcontrib>Andreeva, L. A.</creatorcontrib><creatorcontrib>Anufriev, A. I.</creatorcontrib><creatorcontrib>Kukushkin, N. I.</creatorcontrib><title>Possible reasons for the variability of the inotropic insulin effect in papillary muscles of ground squirrel myocardium</title><title>Biophysics (Oxford)</title><addtitle>BIOPHYSICS</addtitle><description>The effects of insulin (0.1–50 nM) on isometric twitch force (0.1 to 1.0 Hz; 30 ± 1°C; 1.8 mM Ca
2+
) were studied in right ventricular papillary muscles from active ground squirrels of different seasons (summer,
n
= 14; autumn,
n
= 16 and winter interbout,
n
= 16) in control conditions and after one-hour pretreatment of PM with 2 μM nifedipine (an L-type Ca
2+
-channel inhibitor) and 1.0 mM orthovanadate (a tyrosine phosphatase inhibitor). In active animals of different seasonal periods insulin causes both positive and negative inotropic effects. At low frequencies (0.1–0.5 Hz), insulin of low concentrations (0.1–1.0 nM) induces a transient (within the first 20 min after application) positive effect (about 15–25%). Application of high hormone concentration (10 nM) in a low range of stimulation frequencies causes a biphasic effect (a small initial positive inotropic effect followed by a marked negative one). At frequencies above 0.5-Hz stimulation, insulin of 10 nM concentration causes presumably a negative inotropic effect. It was proposed that ICaL is possibly involved in the insulin-induced negative inotropy in ground squirrels hearts. Alteration of protein phosphorylation in tyrosine residues is known to be a major link in the mechanism of insulin action. We performed a study on sodium orthovanadate action (a known inhibitor of tyrosine phosphatase) on the inotropic insulin effect. In the group of summer animals the pretreatment of papillary muscles with sodium orthovanadate (100 μM) does not change the negative inotropic effect of insulin in a low range of stimulation frequencies but almost completely removes this effect at stimulation frequencies above 0.3 Hz (
n
= 4). Nifedipine (1–1.5 h pretreatment), a blocker of L-type calcium channel, reduces the inhibitory effect of insulin in autumn and winter animals, and on the contrary intensifies it in summer animals. This fact indicates that different mechanisms must be involved in insulin actions in animals of summer and winter periods. The main findings of the present study are that insulin induces positive, negative or no inotropic effects in papillary muscles of ground squirrels myocardium. The character of the effects of insulin depends on the physiological state of animals; time and concentrations of the hormone applied; affected by conditions that alter cellular Ca
2+
loading and the ratio of protein-tyrosine kinases/phosphatases activity.</description><subject>Animal populations</subject><subject>Biological and Medical Physics</subject><subject>Biophysics</subject><subject>Complex Systems Biophysics</subject><subject>Heart</subject><subject>Insulin</subject><subject>Physics</subject><subject>Physics and Astronomy</subject><subject>Rodents</subject><issn>0006-3509</issn><issn>1555-6654</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2012</creationdate><recordtype>article</recordtype><recordid>eNp1UE1LxDAQDaLguvoDvAU8VzNNk22PsvgFgoJ6LmmarFmyTXfSKvvvTV0Pgniar_fezDxCzoFdAvDi6oUxJrlgFeRMMmD8gMxACJFJKYpDMpvG2TQ_JicxrhmDghViRj6fQ4yu8YaiUTF0kdqAdHg39EOhU43zbtjRYL9brgsDht7plMXRu44aa40eUkl71TvvFe7oZozamziRVhjGrqVxOzpE4-lmF7TC1o2bU3JklY_m7CfOydvtzevyPnt8untYXj9mGkrOs6pVUBS2KHMl2nT-QpRWCq1lpRYNGKZANo2qlOIaqrbS5QIstwC5Sanmks_JxV63x7AdTRzqdRixSytr4JCDZLwqEwr2KI3JDjS27tFt0jM1sHryt_7jb-Lke05M2G5l8Jfyv6QvKld-Tg</recordid><startdate>20121101</startdate><enddate>20121101</enddate><creator>Nakipova, O. V.</creator><creator>Chumaeva, N. A.</creator><creator>Andreeva, L. A.</creator><creator>Anufriev, A. I.</creator><creator>Kukushkin, N. I.</creator><general>SP MAIK Nauka/Interperiodica</general><general>Springer Nature B.V</general><scope>AAYXX</scope><scope>CITATION</scope><scope>3V.</scope><scope>7QP</scope><scope>7QR</scope><scope>7X7</scope><scope>7XB</scope><scope>88A</scope><scope>88E</scope><scope>88I</scope><scope>8AO</scope><scope>8FD</scope><scope>8FE</scope><scope>8FH</scope><scope>8FI</scope><scope>8FJ</scope><scope>8FK</scope><scope>ABUWG</scope><scope>AFKRA</scope><scope>AZQEC</scope><scope>BBNVY</scope><scope>BENPR</scope><scope>BHPHI</scope><scope>CCPQU</scope><scope>DWQXO</scope><scope>FR3</scope><scope>FYUFA</scope><scope>GHDGH</scope><scope>GNUQQ</scope><scope>HCIFZ</scope><scope>K9.</scope><scope>LK8</scope><scope>M0S</scope><scope>M1P</scope><scope>M2P</scope><scope>M7P</scope><scope>P64</scope><scope>PQEST</scope><scope>PQQKQ</scope><scope>PQUKI</scope><scope>PRINS</scope><scope>Q9U</scope></search><sort><creationdate>20121101</creationdate><title>Possible reasons for the variability of the inotropic insulin effect in papillary muscles of ground squirrel myocardium</title><author>Nakipova, O. V. ; Chumaeva, N. A. ; Andreeva, L. A. ; Anufriev, A. I. ; Kukushkin, N. I.</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c1833-9da144f482a5d350758f65cc69a7b1e0a16bba9aa3c19d9c871f3f112ec87c363</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2012</creationdate><topic>Animal populations</topic><topic>Biological and Medical Physics</topic><topic>Biophysics</topic><topic>Complex Systems Biophysics</topic><topic>Heart</topic><topic>Insulin</topic><topic>Physics</topic><topic>Physics and Astronomy</topic><topic>Rodents</topic><toplevel>online_resources</toplevel><creatorcontrib>Nakipova, O. V.</creatorcontrib><creatorcontrib>Chumaeva, N. A.</creatorcontrib><creatorcontrib>Andreeva, L. A.</creatorcontrib><creatorcontrib>Anufriev, A. I.</creatorcontrib><creatorcontrib>Kukushkin, N. I.</creatorcontrib><collection>CrossRef</collection><collection>ProQuest Central (Corporate)</collection><collection>Calcium & Calcified Tissue Abstracts</collection><collection>Chemoreception Abstracts</collection><collection>ProQuest Health and Medical</collection><collection>ProQuest Central (purchase pre-March 2016)</collection><collection>Biology Database (Alumni Edition)</collection><collection>Medical Database (Alumni Edition)</collection><collection>Science Database (Alumni Edition)</collection><collection>ProQuest Pharma Collection</collection><collection>Technology Research Database</collection><collection>ProQuest SciTech Collection</collection><collection>ProQuest Natural Science Collection</collection><collection>Hospital Premium Collection</collection><collection>Hospital Premium Collection (Alumni Edition)</collection><collection>ProQuest Central (Alumni) (purchase pre-March 2016)</collection><collection>ProQuest Central (Alumni)</collection><collection>ProQuest Central</collection><collection>ProQuest Central Essentials</collection><collection>Biological Science Collection</collection><collection>AUTh Library subscriptions: ProQuest Central</collection><collection>ProQuest Natural Science Collection</collection><collection>ProQuest One Community College</collection><collection>ProQuest Central</collection><collection>Engineering Research Database</collection><collection>Health Research Premium Collection</collection><collection>Health Research Premium Collection (Alumni)</collection><collection>ProQuest Central Student</collection><collection>SciTech Premium Collection</collection><collection>ProQuest Health & Medical Complete (Alumni)</collection><collection>ProQuest Biological Science Collection</collection><collection>Health & Medical Collection (Alumni Edition)</collection><collection>PML(ProQuest Medical Library)</collection><collection>ProQuest Science Journals</collection><collection>ProQuest Biological Science Journals</collection><collection>Biotechnology and BioEngineering Abstracts</collection><collection>ProQuest One Academic Eastern Edition (DO NOT USE)</collection><collection>ProQuest One Academic</collection><collection>ProQuest One Academic UKI Edition</collection><collection>ProQuest Central China</collection><collection>ProQuest Central Basic</collection><jtitle>Biophysics (Oxford)</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Nakipova, O. V.</au><au>Chumaeva, N. A.</au><au>Andreeva, L. A.</au><au>Anufriev, A. I.</au><au>Kukushkin, N. I.</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Possible reasons for the variability of the inotropic insulin effect in papillary muscles of ground squirrel myocardium</atitle><jtitle>Biophysics (Oxford)</jtitle><stitle>BIOPHYSICS</stitle><date>2012-11-01</date><risdate>2012</risdate><volume>57</volume><issue>6</issue><spage>796</spage><epage>803</epage><pages>796-803</pages><issn>0006-3509</issn><eissn>1555-6654</eissn><abstract>The effects of insulin (0.1–50 nM) on isometric twitch force (0.1 to 1.0 Hz; 30 ± 1°C; 1.8 mM Ca
2+
) were studied in right ventricular papillary muscles from active ground squirrels of different seasons (summer,
n
= 14; autumn,
n
= 16 and winter interbout,
n
= 16) in control conditions and after one-hour pretreatment of PM with 2 μM nifedipine (an L-type Ca
2+
-channel inhibitor) and 1.0 mM orthovanadate (a tyrosine phosphatase inhibitor). In active animals of different seasonal periods insulin causes both positive and negative inotropic effects. At low frequencies (0.1–0.5 Hz), insulin of low concentrations (0.1–1.0 nM) induces a transient (within the first 20 min after application) positive effect (about 15–25%). Application of high hormone concentration (10 nM) in a low range of stimulation frequencies causes a biphasic effect (a small initial positive inotropic effect followed by a marked negative one). At frequencies above 0.5-Hz stimulation, insulin of 10 nM concentration causes presumably a negative inotropic effect. It was proposed that ICaL is possibly involved in the insulin-induced negative inotropy in ground squirrels hearts. Alteration of protein phosphorylation in tyrosine residues is known to be a major link in the mechanism of insulin action. We performed a study on sodium orthovanadate action (a known inhibitor of tyrosine phosphatase) on the inotropic insulin effect. In the group of summer animals the pretreatment of papillary muscles with sodium orthovanadate (100 μM) does not change the negative inotropic effect of insulin in a low range of stimulation frequencies but almost completely removes this effect at stimulation frequencies above 0.3 Hz (
n
= 4). Nifedipine (1–1.5 h pretreatment), a blocker of L-type calcium channel, reduces the inhibitory effect of insulin in autumn and winter animals, and on the contrary intensifies it in summer animals. This fact indicates that different mechanisms must be involved in insulin actions in animals of summer and winter periods. The main findings of the present study are that insulin induces positive, negative or no inotropic effects in papillary muscles of ground squirrels myocardium. The character of the effects of insulin depends on the physiological state of animals; time and concentrations of the hormone applied; affected by conditions that alter cellular Ca
2+
loading and the ratio of protein-tyrosine kinases/phosphatases activity.</abstract><cop>Dordrecht</cop><pub>SP MAIK Nauka/Interperiodica</pub><doi>10.1134/S0006350912060103</doi><tpages>8</tpages></addata></record> |
fulltext | fulltext |
identifier | ISSN: 0006-3509 |
ispartof | Biophysics (Oxford), 2012-11, Vol.57 (6), p.796-803 |
issn | 0006-3509 1555-6654 |
language | eng |
recordid | cdi_proquest_journals_1312160398 |
source | Springer Nature |
subjects | Animal populations Biological and Medical Physics Biophysics Complex Systems Biophysics Heart Insulin Physics Physics and Astronomy Rodents |
title | Possible reasons for the variability of the inotropic insulin effect in papillary muscles of ground squirrel myocardium |
url | http://sfxeu10.hosted.exlibrisgroup.com/loughborough?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2024-12-25T13%3A18%3A44IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-proquest_cross&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Possible%20reasons%20for%20the%20variability%20of%20the%20inotropic%20insulin%20effect%20in%20papillary%20muscles%20of%20ground%20squirrel%20myocardium&rft.jtitle=Biophysics%20(Oxford)&rft.au=Nakipova,%20O.%20V.&rft.date=2012-11-01&rft.volume=57&rft.issue=6&rft.spage=796&rft.epage=803&rft.pages=796-803&rft.issn=0006-3509&rft.eissn=1555-6654&rft_id=info:doi/10.1134/S0006350912060103&rft_dat=%3Cproquest_cross%3E2900477731%3C/proquest_cross%3E%3Cgrp_id%3Ecdi_FETCH-LOGICAL-c1833-9da144f482a5d350758f65cc69a7b1e0a16bba9aa3c19d9c871f3f112ec87c363%3C/grp_id%3E%3Coa%3E%3C/oa%3E%3Curl%3E%3C/url%3E&rft_id=info:oai/&rft_pqid=1312160398&rft_id=info:pmid/&rfr_iscdi=true |