Endogenous digitalis-like substance in pig left ventricle

Khatter, Jagdish C.; Agbanyo, M.; Hoeschen, Robert J.

doi:10.1016/0024-3205(86)90491-1

Cited by 10 publications

(9 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The detailed methodology for the isolation of the crude porcine ventricular extract has been described previously (Khatter et al, 1986). A homogenate of the porcine left ventricle was obtained, lipids were extracted with methanol and diethyl ether and the fraction subjected to column chromatography (Sephadex G-25-80 fine bead) and desalting.…”

Section: Methods Isolation Ofdigitalis-like Substance (Dls)-containinmentioning

confidence: 99%

“…The crude extract obtained in our laboratory from porcine ventricle was consistently inotropic in guinea-pig isolated hearts (Khatter et al, 1986). Furthermore, in our previous studies we also excluded the possibility of catecholamines being responsible for the inotropic effect because: (a) it was not blocked by a 8-adrenoceptor antagonist, (b) the extract did not compete for [3H]-(-)-dihydroalprenolol binding (Khatter et al, 1986) and (c) in high performance liquid chromatography (h.p.l.c.) analysis it did not have similar peaks as those of adrenaline, noradrenaline or dopamine .…”

Section: Introductionmentioning

confidence: 96%

“…has been attempted by many laboratories (Gruber et al, 1980;Kelly et al, 1985;Balzan et al, 1986, Ebara et al, 1986). In our laboratory, we isolated a crude fraction from porcine left ventricle, after extraction of lipids, chromatographic separation and desalting (Khatter et al, 1986). The extract had digitalis-like properties such as inhibition of cardiac and kidney Na', K+-ATPase dose-dependently, displacement of [3H]-ouabain from its binding sites and cross reactivity with antibodies to digoxin (Khatter et al, 1986;Khatter et al, 1990).…”

Section: Introductionmentioning

confidence: 99%

“…In our laboratory, we isolated a crude fraction from porcine left ventricle, after extraction of lipids, chromatographic separation and desalting (Khatter et al, 1986). The extract had digitalis-like properties such as inhibition of cardiac and kidney Na', K+-ATPase dose-dependently, displacement of [3H]-ouabain from its binding sites and cross reactivity with antibodies to digoxin (Khatter et al, 1986;Khatter et al, 1990). We also investigated the effect of this extract on 86Rb uptake, which is a representation of functional Na' pump activity.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Positive inotropic effect of porcine left ventricular extract on canine ventricular muscle

Navaratnam

Chau

Agbanyo

et al. 1990

British J Pharmacology

Self Cite

View full text Add to dashboard Cite

1 We previously isolated an extract from porcine left ventricle that possessed digitalis-like properties such as inhibition of cardiac and kidney Na+, K+-ATPase, displacement of [3H]-ouabain from its binding sites and cross reactivity with digoxin antibodies. The extract also had a positive inotropic effect on the guinea-pig heart. 2 In the present study the positive inotropic response of the extract was characterized in canine right ventricular trabeculae. Maximum inotropic response (501 + 20%) was produced by 300,1 and the half maximal increase occurred with 125 ,ul of the extract. 3 Ouabagenin produced aftercontractions in rapidly paced trabeculae. Equipotent and even greater amounts of the extract did not produce aftercontractions. 4 The extract increased the amplitude of the delayed component (P2) of biphasic contractions produced by replacing about 92-96% of the external Ca with Sr. A smaller increase in the size of the early component (P1) was also seen. 5 The extract decreased post-rest potentiation after rest for 30s and 2 min. After 8 min of rest, post-rest potentiation was converted to post-rest depression.6 The extract (20#u1) produced a decrease in the amplitude of the post-rest rapid cooling contracture (RCC) at all rest intervals. The steady state RCC, although greater than that in the control muscle, was increased to a lesser extent than the size of the steady state electrically driven contractions. 7 It is suggested that the extract from porcine left ventricle produces a positive inotropic response by increasing the trans-sarcolemmal influx of Ca. It also has additional effect(s) on the sarcoplasmic reticulum in that it may facilitate the loss of Ca from the sarcoplasmic reticulum and/or inhibit the uptake of Ca by the organelle.

show abstract

Section: Methods Isolation Ofdigitalis-like Substance (Dls)-containinmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Positive inotropic effect of porcine left ventricular extract on canine ventricular muscle

Navaratnam

Chau

Agbanyo

et al. 1990

British J Pharmacology

Self Cite

View full text Add to dashboard Cite

show abstract

“…We have previously reported isolation of an endogenous factor from porcine heart left ventricle (Khatter et al, 1986). This factor was characterized pharmacologically as an endogenous inotropic factor (EIF).…”

Section: Introductionmentioning

confidence: 99%

Endogenous inotropic factor‐induced endothelium‐dependent relaxation of vascular smooth muscle

Han

Khatter

1996

British J Pharmacology

View full text Add to dashboard Cite

0Z31 Possible contractile or relaxation effects of an endogenous inotropic factor (EIF) isolated and purified from porcine heart left ventricle were examined in rat isolated aortic ring preparations. 2 EIF induced a dose-dependent relaxation of the rat isolated aortic ring preparation pre-contracted with 0.4 /M phenylephrine (PE); 200 Ml (in 5 ml bath) of EIF caused relaxation of aortic rings by as much as 67.4+4.5%. In another set of experiments, in the presence of 100 yl EIF, the PE concentrationresponse contractile curve shifted to the right, the maximal contractile force was reduced by as much as 32.8% and the EC50 of PE increased from 0.2 to 0.3 gM. 3 The relaxation effect of EOF was demonstrated to be endothelium-dependent. Additional experiments demonstrated that EIF-induced relaxation in an isolated aortic ring could be inhibited by 2 gM NG-nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor, suggesting the involvement of nitric oxide in EIF-induced relaxation of the muscle.4 Atropine (0.2 gM) or indomethacin (10 gM) had no significant effect on EIF-induced relaxation.5 These data suggest that EIF, a novel endogenous inotrope from porcine myocardium, also acts as an endothelium-dependent vasodilator substance mediating relaxation in the rat isolated aorta mainly by release of nitric oxide. The possibility of EIF acting through muscarinic receptor and the involvement of prostacyclin were excluded.

show abstract

An endogenous positive inotropic factor (EPIF) from porcine heart: Its effects on sarcoplasmic reticular (SR) Ca2+ metabolism

Khatter

Agbanyo

Böse

et al. 1997

The Cellular Basis of Cardiovascular Function in Health and Disease

View full text Add to dashboard Cite

Endogenous digitalis-like substance in pig left ventricle

Cited by 10 publications

References 17 publications

Positive inotropic effect of porcine left ventricular extract on canine ventricular muscle

Positive inotropic effect of porcine left ventricular extract on canine ventricular muscle

Endogenous inotropic factor‐induced endothelium‐dependent relaxation of vascular smooth muscle

An endogenous positive inotropic factor (EPIF) from porcine heart: Its effects on sarcoplasmic reticular (SR) Ca2+ metabolism

Contact Info

Product

Resources

About