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S Rodriguez

Publications and source records attributed to S Rodriguez.

At least 145 records · Page 8Linked to original sources
PubMed1980

Electrophysiological effects of imipramine on bovine ventricular muscle and Purkinje fibres.

1 The effect of imipramine in concentrations between 0.01 microM and 50 microM has been studied on bovine Purkinje fibres and ventricular muscle transmembrane potentials. 2 In electrically stimulated fibres, imipramine had no effect on the resting membrane potential, but decreased the action potential amplitude, overshoot and maximum rate of depolarization (Vmax). 3 In Purkinje fibres, imipramine also decreased the conduction velocity and shifted the membrane responsiveness and recovery time curves downward and to the right. 4 In both Purkinje fibres and ventricular muscle, imipramine decreased the amplitude of phase 2 and prolonged phase 3. In Purkinje fibres, imipramine did not alter the action potential duration (APD) but prolonged the effective refractory period (ERP). In ventricular muscle, at concentrations higher than 1 microM imipramine shortened both the APD and the ERP and made the ERP long as compared to APD. 5 Imipramine decreased the slope of phase 4 diastolic depolarization in spontaneously beating Purkinje fibres. 6 These properties of imipramine are quite similar to those of quinidine or procainamide (class 1 antiarrhythmics). The mechanisms responsible for the cardiac effect of imipramine are discussed.

Action Potentials↗
PubMed1979

Electrophysiological effects of desipramine on guinea pig papillary muscles.

The effects of desipramine (DMI) in concentrations between 1 x 10(-7) M and 1 x 10(-4) M on various electrophysiological parameters were evaluated in ventricular papillary muscles of guinea pig. At concentrations less than 5 x 10(-5) M, DMI produced a significant shortening in the action potential duration (APD) measured at both 50% and 100% of repolarization. At 1 x 10(-4) M, the terminal portion of repolarization was so prolonged that the total APD was not significantly different from control values. DMI (greater than 1 X 10(-5) M) did not change the resting potential but significantly, decreased the overshoot potential, the amplitude, and the maximum rate of rise of phase O depolarization (Vmax) and shifted the membrane responsiveness and membrane reactivation curves downward and to the right. The effective refractory period (ERP) was shortened or lengthened, the effect being dependent on the concentration, but always made the ERP long relative to APD. DMI, (1 X 10(-5) M and 5 x 10(-5) M), attenuated and abolished the spontaneous activity and the Ca-mediated action potentials induced in ventricular muscle fibers. The mechanisms responsible for DMI's in vivo arrhythmogenic or antiarrhythmic effects are discussed. In terms of changes in ion conductance most effects can be explained by a reduction in sodium and calcium conductance.

Action Potentials↗
PubMed1979

Electrophysiological actions of chlorimipramine on guinea-pig ventricular fibres.

Chlorimipramine (CMI, 1 x 10(-5)M to 7 X 10(-5)M) decreased the amplitude, overshoot and rate of rise of ventricular action potentials and abolished the Ca-mediated action potentials elicited in guinea-pig papillary muscles. These results indicates that CMI inhibits the rise in sodium and calcium conductances during the cardiac action potential.

Action Potentials↗
PubMed1975

Levator ani as substitute puborectalis sling in treatment of anal incontinence.

For anal incontinence caused by destroyed or absent sphincter mechanism, a levator sling serving as a substitute puborectalis sling was used in five patients with incontinence of varied causes with good to excellent results. This sling was constructed bu freeing the insertion of the pubococcygeus and the ileococcygeus muscles from the coccyx. By further freeing the arcus tendineus from the lateral wall of the pelvis, the sling is made to arise from the pubis, thus theoretically giving the sling the potential of greater traction.

Fecal Incontinence↗
PubMed1967

Renal angiomas.

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Adult↗
PubMedDate not supplied

The Warren operation for anal incontinence caused by disruption of the anterior segment of the anal sphincter, perineal body, and rectovaginal septum: report of five cases.

The use of the Warren vaginal flap operation for repair of a traumatic deformity consisting of disruption of the perineal body, anterior segment of the external anal sphincter, and lower half of the rectovaginal septum is described. Modifications described in this article include use of the jackknife position to give better exposure and epinephrine infiltration to give a bloodless field. The incidences of infection and recurrence appear lower than with the layer technique.

Adult↗
PubMedDate not supplied

Amenorrhea-galactorrhea associated with Cushing's disease due to pituitary tumor.

Two patients with amenorrhea-galactorrhea and Cushing's disease due to pituitary tumor are presented. In both cases, a diagnosis of prolactin-secreting tumor with moderate hyperprolactinemia was established, then Cushing's disease developed years later. Despite the typical clinical features of Cushing's disease, a dexamethasone suppression test inhibited both blood ACTH and cortisol concentrations in the 2 patients. Hypophysectomy was performed in 1 case, and the histologic study revealed the presence of a cromophobe adenoma. The other case was treated by external radiation which improved the clinical situation. Clinical and endocrinological studies in these 2 cases were compared with previous reports in the literature in order to discuss the etiology of this unusual association. It is concluded that patients with pituitary tumors presenting moderate hyperprolactinemia may also have excessive secretion of ACTH.

Adenoma, Chromophobe↗