Oral labetalol versus oral nifedipine in hypertensive urgencies in the ED.

Therapy in hypertensive urgencies is debated and complicated by the side effects of available agents. In a prospective, randomized, open labeled study, the use of oral labetalol, an alpha- and beta-adrenergic blocker, with oral nifedipine in hypertensive urgencies in the emergency department was compared. Patients with diastolic blood pressures (DBP) of more than 120 mm Hg without criteria for a hypertensive emergency were eligible. The drugs were given in a loading manner with doses and timing based on their respective pharmacokinetics until a DBP of 110 mm Hg or lower was obtained or 4 hours had passed. Either an initial labetalol dose of 200 mg and a repeat dose of 100 to 200 mg at 2 hours, depending on the DBP or nifedipine, 10-mg bite and swallow every hour up to a total dose of 20 mg were given. Ten patients were enrolled into each study group. A 100% response rate was defined as a DBP of 110 mm Hg or less was observed for nifedipine and an 80% response rate for labetalol (P > .2) was observed. The mean time to control was 67.5 minutes for labetalol and 60.0 minutes for nifedipine (P > .2). The pretreatment pressure for labetalol was 195/127 mm Hg and for nifedipine was 198/128 mm Hg (P > .2), which decreased to a posttreatment pressure for labetalol of 154/100 mm Hg and for nifedipine of 163/100 mm Hg (P > .2). The mean decrease in systolic (SBP)/DBP was 42.6/26.5 mm Hg with labetalol and 34.9/28.4 mm Hg for nifedipine (P > .2). No significant side effects occurred with either drug.(ABSTRACT TRUNCATED AT 250 WORDS)

Projections of the intermediate subdivision of the central amygdaloid nucleus to the bed nucleus of the stria terminalis and medial diencephalon.

The forebrain projections of the intermediate subdivision of the central amygdaloid nucleus (CI) were studied using the horseradish peroxidase (HRP) retrograde transport technique. Injections of wheatgerm agglutinin-conjugated HRP into the bed nucleus of the stria terminalis and medial thalamus resulted in moderate retrograde labeling in CI while injections into the medial hypothalamus produced very dense cell labeling in CI. The dorsal hypothalamic area appears to be the main target of the efferents to the hypothalamus. Although previous histochemical studies have suggested that CI may be part of the lateral subdivision of the central nucleus (CL), the projection of CI to the medial diencephalon clearly distinguishes CI from CL.

Somatostatinergic projections from the amygdala to the bed nucleus of the stria terminalis and medial preoptic-hypothalamic region.

Somatostatinergic projections of the amygdala to the bed nucleus of the stria terminalis (BST) and medial preoptic-hypothalamic region were examined using a technique that combines retrograde axonal transport with peroxidase-antiperoxidase immunohistochemistry. With injections of wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) into either the BST or medial preoptic-hypothalamic region numerous double-labeled cells exhibiting both retrograde labeling and somatostatin-like immunoreactivity were observed in the medial amygdaloid nucleus and intra-amygdaloid portion of the BST. Additional cells were seen in the central nucleus, basomedial nucleus and anterior amygdaloid area. Although WGA-HRP labeled neurons and somatostatin-positive cells were observed in the lateral and basolateral amygdaloid nuclei, few double-labeled neurons were found.