Desensitisation of Sigma Receptors in Guinea Pig Atria

D 2003

Desensitisation of Sigma Receptors in Guinea Pig Atria

NOVÁKOVÁ, Marie

Základní údaje

Originální název

Desensitisation of Sigma Receptors in Guinea Pig Atria

Autoři

NOVÁKOVÁ, Marie

Vydání

Plzeň, 79. Fyziologické dny, Sborník abstraktů, s. 41-41, 2003

Nakladatel

Lékařská fakulta University Karlovy v Plzni

Další údaje

Jazyk

angličtina

Typ výsledku

Stať ve sborníku

Obor

30105 Physiology

Stát vydavatele

Česká republika

Utajení

není předmětem státního či obchodního tajemství

Organizační jednotka

Lékařská fakulta

Klíčová slova anglicky

guinea pig heart; cardiac sigma receptor; desensitisation; haloperidol; mechanical restitution

Štítky

cardiac sigma receptor, desensitisation, guinea pig heart, haloperidol, Mechanical restitution

Změněno: 11. 2. 2003 15:29, prof. MUDr. Marie Nováková, Ph.D.

Anotace

V originále

Previous studies have shown a modulatory effect of sigma receptor activation on cardiac contractility and its desensitisation in rat myocardium. This study was aimed at verifying the effects of sigma ligands in a more typical model, i.e. guinea pig atria. Left atriafrom 19 adult male guinea pigs were placed in horizontal perfusion bath (30C) with aerated Krebs-Henseleit solution (1.25 mM Ca2+). The stimulation rate was 1Hz. Contractions were recorded isometrically. After 30-45 minutes of stabilisation, sigma ligand haloperidol in 10nM concentration was administered for 30 minutes. Then, a period of 15 min washout and another 30 min period of haloperidol perfusion followed. The changes of amplitude of contraction and of mechanical restitution were investigated. In all cases, marked positive inotropic effect was observed (increase in the amplitude ranging from 36 to 123%, with maximal effect in the 5th minute of perfusion). The mechanical restitution pattern under the effect of sigma receptor ligand was not altered. This positive inotropic effect was attenuated after the second haloperidol administration (an increase in the amplitude ranging from 9 to 93%, with the maximum effect in the 3rd minute). In conclusion: the positive inotropic effect of haloperidol, previously described in rat myocardium, was confirmed also in guinea pig atrial preparations. Its attenuation after the repeated exposure indicates that sigma receptors in guinea pig heart undergo a desensitisation process previously reported in rat myocardium. According to the effect of haloperidol on the mechanical restitution it is possible to speculate that it is mediated via increased availability of cytoplasmatic calcium.

Návaznosti

GA102/01/1494, projekt VaV

Název: Optické snímání akčních potenciálů a jeho využití v kardiologii

Investor: Grantová agentura ČR, Optické snímání akčních potenciálů a jeho využití v kardiologii

Citovat

NOVÁKOVÁ, Marie. Desensitisation of Sigma Receptors in Guinea Pig Atria. In 79. Fyziologické dny, Sborník abstraktů. Plzeň: Lékařská fakulta University Karlovy v Plzni, 2003, s. 41.

@inproceedings{484498,
   author = {Nováková, Marie},
   address = {Plzeň},
   booktitle = {79. Fyziologické dny, Sborník abstraktů},
   keywords = {guinea pig heart; cardiac sigma receptor; desensitisation; haloperidol; mechanical restitution},
   language = {eng},
   location = {Plzeň},
   pages = {41-41},
   publisher = {Lékařská fakulta University Karlovy v Plzni},
   title = {Desensitisation of Sigma Receptors in Guinea Pig Atria},
   year = {2003}
}

TY  - JOUR
ID  - 484498
AU  - Nováková, Marie
PY  - 2003
TI  - Desensitisation of Sigma Receptors in Guinea Pig Atria
PB  - Lékařská fakulta University Karlovy v Plzni
CY  - Plzeň
KW  - guinea pig heart
KW  - cardiac sigma receptor
KW  - desensitisation
KW  - haloperidol
KW  - mechanical restitution
N2  - Previous studies have shown a modulatory effect of sigma receptor activation on cardiac contractility and its desensitisation in rat myocardium. This study was aimed at verifying the effects of sigma ligands in a more typical model, i.e. guinea pig atria. Left atriafrom 19 adult male guinea pigs were placed in horizontal perfusion bath (30C) with aerated Krebs-Henseleit solution (1.25 mM Ca2+). The stimulation rate was 1Hz. Contractions were recorded isometrically. After 30-45 minutes of stabilisation, sigma ligand haloperidol in 10nM concentration was administered for 30 minutes. Then, a period of 15 min washout and another 30 min period of haloperidol perfusion followed. The changes of amplitude of contraction and of mechanical restitution were investigated. In all cases, marked positive inotropic effect was observed (increase in the amplitude ranging from 36 to 123%, with maximal effect in the 5th minute of perfusion). The mechanical restitution pattern under the effect of sigma receptor ligand was not altered. This positive inotropic effect was attenuated after the second haloperidol administration (an increase in the amplitude ranging from 9 to 93%, with the maximum effect in the 3rd minute). In conclusion: the positive inotropic effect of haloperidol, previously described in rat myocardium, was confirmed also in guinea pig atrial preparations. Its attenuation after the repeated exposure indicates that sigma receptors in guinea pig heart undergo a desensitisation process previously reported in rat myocardium. According to the effect of haloperidol on the mechanical restitution it is possible to speculate that it is mediated via increased availability of cytoplasmatic calcium.
ER  -

NOVÁKOVÁ, Marie. Desensitisation of Sigma Receptors in Guinea Pig Atria. In \textit{79. Fyziologické dny, Sborník abstraktů}. Plzeň: Lékařská fakulta University Karlovy v Plzni, 2003, s.~41.

Podrobný výpis o publikaci