R(+)-pulegone impairs [Ca.sup.2+] homeostasis and causes negative inotropism
in mammalian myocardium.
When the patient "moves" in phase 1 of the curve, preload is directly proportional to the systolic volume; the variations of pulse are broad, indicating that the patient is dependent on the preload or that the patient will respond to the volumen (2,3,10) (responder or dependent on volume), while if the patient is moved to phase 2 of the Starling curve the variations in pulse pressure are minimal, indicating that the patient will not respond to the liquid infusion or that what is probably required is to strengthen cardiac inotropism
to increase cardiac output and avoid an overload of liquids that can lead to pulmonary edema (2,3,10) (non-responder or not dependent on volume).
Coronary vasodilation and positive inotropism
by urocortin in the isolated rat heart.
Levosimendan activates [K.sub.ATP] channels in rat isolated cardiac mitochondria (52) (Figure 2) and ventricular cells (6) with [EC.sub.50] values of 0.83 and 4.7 [micro]M, respectively; values which are different from those required for inotropism
. Further, during ischaemia, as the intracellular ADP: adenosine triphosphatase (ATP) ratio increases, the potency of levosimendan may be potentially enhanced.
Rather, it can be attributed to enhanced mental alertness or an increase in a phenomenon scientists call cardiac inotropism
. Actual changes in blood pressure cannot be "felt."
In the heart, the release of [Ca.sup.2+] from intracellular stores leads to an increase of heart rate and cardiac inotropism
and to vasodilatation [36-38].
BP studies have shown the following in vitro effects in rodent tissue: positive inotropism
, sedation, analgesic activity, H1 antagonism (ileum, bronchial muscle, peripheral vasculature), and antimicrobial activity (Oliver-Bever 1983; Pal et al.
Heart rate, cardiac inotropism
and, hence, blood pressure (BP) increase with stimulation of [[beta].sub.1] adrenergic receptors and decrease with their blockade.