DOUBLE-PEAKED POSITIVE CHRONOTROPIC RESPONSES OF ISOLATED AND CROSS-PERFUSED DOG ATRIA TO ATP
نویسندگان
چکیده
منابع مشابه
Double peaked positive chronotropic response of the isolated blood-perfused S-A node to caffeine.
peaked positive chronotropic responses, i.e., rapidly induced initial acceleration followed by slowly induced but long-lasting one. The initial positive response to caffeine was hardly suppressd by either adrenergic beta-blocking agents, H 56/28 (alprenolol) and propranolol, or tetrodotoxin. On the contrary, the secondary positive chronotropic response was effectively inhibited by either adrene...
متن کاملSelective reserpine-induced supersensitivity of the positive inotropic and chronotropic responses to isoprenaline and salbutamol in guinea-pig isolated atria.
1 Dose-response curves for the positive inotropic and chronotropic responses to isoprenaline were obtained in atria from untreated guinea-pigs and those receiving various reserpine pretreatments. 2 Tension responses were unaffected, whereas rate responses were depressed by the lowest dose of reserpine (0.05 mg/kg i.p. at 24 hours). 3 With larger 24 h doses and a 3 day pretreatment, the rate and...
متن کاملLong-term nitric oxide inhibition and chronotropic responses in rat isolated right atria.
The long-term administration of nitric oxide synthesis inhibitors induces arterial hypertension accompanied by left ventricular hypertrophy and myocardial ischemic lesions. Because the enhancement of sympathetic drive has been implicated in these phenomena, the current study was performed to determine the potency of beta-adrenoceptor agonists and muscarinic agonists on the spontaneous rate of i...
متن کاملNovel cilostamide analogs, phosphodiesterase 3 inhibitors, produce positive inotropic but differential lusitropic and chronotropic effects on isolated rat atria
Objective(s): Recently, we showed that some new synthetic compounds structurally related to cilostamide (4-(1,2-dihydro-2-oxoquinolin-6-hydroxy)- N-cyclohexyl-N-methylbutanamide), a selective phosphodiesterase 3 (PDE3) inhibitor, produce inotropic effect comparable to that of IBMX (3-isobutyl-1-methylxanthine), a non-selective PDE inhibitor, but with differential chronotropic effect. In this in...
متن کاملA negative inotropic effect of omega-conotoxin GVIA in isolated, blood-perfused dog right atria.
Using an isolated, blood-perfused canine atrial preparation, we investigated the effects of omega-conotoxin GVIA (omega-CgTX), a blocker of N-type voltage-operated calcium channels, on the atrial contractile force and sinus rate. Omega-CgTX in a dose range of 0.3-3 nmol gradually attenuated the atrial contractile force in a dose-dependent manner, but did not affect the sinus rate, indicating th...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Japanese Journal of Pharmacology
سال: 1983
ISSN: 0021-5198
DOI: 10.1016/s0021-5198(19)52420-9